BS 4465 (1989) Electric Hoists

as 4465 : 1989UDC 621.876.1-83:69.057.7

British Standard Specification for

Design and construction of electric hoistsfor both passengers and materials

iiiii!!!!!!!iiiiiiiiii

iiiiiiiii!!!!!!!

*(f)

* Conception et construction des elt~vateursde personnel et monte-charge electriques - Specifications

Ausfuhrung und Konstruktion von elektrischen Personen- und Lastenaufzugen

FRANKLIN OFFSHORE EUROPE LTD

CONTROLLED COPY. THIS DOCUMENT

WILL BE UPDATED WHEN REQUIRED

FRANKLIN OFFSHORE EUROPE lTDCONTROLLED COPY. THIS DOCUMENT

_WILL BE UPDATEDWHEN REQUIRED -.-

1Im~1INO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW

British Standards

BS 4465 : 1989

Foreword

This British Standard, prepared under the direction of theMechanical Handling Standards Policy Committee at therequest of the Health and Safety Executive, is a new editionof BS 4465 : 1986, which is withdrawn. This edition intro-duces technical changes to bring the standard up-to-datebut it does not reflect a full review of the standard, whichwill be undertaken in due course. It specifies requirementsfor hoists carrying both passengers and materials used inconstruction work and applies to machines employingrope suspended cages driven by drum and traction, and alsoto rack and pinion drive machines.

The primary object of the standard is to promote reliabilityand safety without placing undue restrictions on the generaldesign of hoists or methods employed in their constructionand erection.

The standard follows closely the requirements specified indraft European Standard prEN 109. It was originallyenvisaged that EN 109 would be directly implemented asthe revision of this British Standard but, owing to adminis-trative problems, final publication of the European Standardcannot be anticipated for some considerable time. However,upon the publication of EN 109 this standard may berevised to implement that European Standard.

The design practice in this specification is based upon thatfor cranes and thus the structural requirements specified inthis standard are similar to those specified in BS 2573 :Part 1.

Account has also been taken of BS 5655 : Part 1 for electriclifts. There are however some radical departures from liftdesign practice in this standard, these being necessitated bysuch factors as the open air environment of the hoist,and the need for its periodic dismantling, re-erection andextension in service.

...~.""{ ,

It is assumed that a base structure and other supports willbe provided on the construction site which will support andresist all loads, moments and overturning forces which maydevelop due to the use of the hoist, wind forces and other.in.cidanal-fOfiteS '6" lhe ..IClst mmNij .11Hi'~klJo~ledQedA1i!i~ ftbJ~t~~~ d to carry bothpassengers 1!tIdm3teri~JdD1ti_ ". ge larger than that

re~irecrtor-'~s~~~ers 9l1W.~, 9~~carry bulky but not

l1ec:essatilyheavy objec~. ')15 eJ~r)ti., therefore, that usersof these h()4Jt~'eilterc:~eQJa{e 'lSb'Ht

tl over their loading.

C9.J1~ipl!ra1;j,p.Q~ouJd.l?egW8fItPt'II\'t; stallation of over-10adWarning~evices.lt is anticip~1~'t. at a code of practicewiJ1 be,prepared on-t~safem$'tmlaHo~ and use of the

__~ ~. ..boiUs.,eovar.eQ.ey.tnfs ~talldal 11:-'----

BS 7212J!1!1.~~~~Q~el.d8tl~for the selection of

r rpp~ji,'I1.Q.,t$Pfst~i' A'H~ng down safe systems

(11 ' 3<10<lU3 Oj~"tUSClf&ltlVt!~ nd planning ofthe

~

".J J . I. ,,, _.,j.gA.II.!\t;oll,"1~stiri9. examinati0,q. peration and mainte-_.~.-,. ",/lqqce ~CP~~ft~jf9~~clf~'41s ell as giving guidance

\ T\~3MU~OO:'$n \hE!'~~I!e~ty'0~4af1dt~)j1iJlRV¥"ertors and operators.

\ n. ':1"in,. .~~~diJ<]i{ tMs l\Jg\SI~fibn;"MgUla.\lonsand related

i ,.0"3t:. ".,,~ documents thatmay-be' dfJPtfCiib1e to electric hoists.i

Compliance with a British Standard does not of itselfconfer immunity from legal obligations.

,

\\iI1 ,

Page PageForeword Inside front cover E Basic formula for calculation of C, 50Committees responsible Back cover F Text deleted 50

G Certificate of type test for safety gear 61Specification

Section one. General Tables1 Scope 2 1 List of loads 32 Definitions 2 2 Load combinations 33 Design considerations 2 3 I mpact factors 3

4 Design wind pressures 4Section two. Structural design and construction 6 Force coefficients Cf 5

4 Loads and load combinations 3 6 Shielding factors q, 56 Selection of steel, minimum thickness and 7 Basic stresses in structural members 9

working stresses 6 8 Values of Robertson constant Q for struts of6 Stresses in structural components 8 various sections 107 Basic stresses in connections 21 9 Values of Fcrlp for steels complying with8 Proportions of structural components, plates BS 4360 11

and web stiffeners 24 10 Values of K1 139 Fluctuating loads: permissible fatigue stresses 29 11 Values of K2 13

12 Values of A and 8 to be used for calculatingSection three. Mechanical design and construction values of C, 1510 Hoist cage and enclosure 36 13 Basic stress Pbc,b81 for different values of11 Hoistway enclosure and gates 36 critical stress C, 16

iiiiiii 14 Basic average shear stress Pq,b81 in stiffened!!!!!! 12 Interlocking of gates 36iiiiiii13 Rope suspension 37 webs of steel complying with BS 4360 18iiiiiii

iiiiiii 14 Rack and pinion suspension system 38 16 Basic stresses in welds 22!!!!!! 15 Driving machinery 38 16 Basic stresses in rivets as a percentage of YRO.2 24

*16 Brake 39 17 Effective lengths of parts in compression 24

(J) 17 Counterweights 39 18 Effective lenCl1:hwith no lateral bracing 26* 18 Safety gear 19 Maximum width of plates in compression 2740

19 Overspeed governors 40 20 Projection of unstiffened compression flange20 Buffers 40 plates 2721 Hoist cage overrun 41 21 Values of P for fluctuating stresses for various22 Safety switches 41 classes of constructional details 3123 Guarding 41 22 Size of perforation or opening in cage enclosure24 Noticas 42 related to clearance 36

23 Clearance betWeen turns of rope on helicallySection four. Electrical design and construction grooved drums 3826 Mains supply isolating switch 43

24 Type of safety gear for counterweights 4026 Cables and wiring 43

26 Governor tripping speeds 4027 Protection against the effects of external

influences 43 Figures28 Earthing 43 1 Conversion chart for wind speed and pressure 629 Control circuits, panels, equipment and systems 43 2 Definitions: aerodynamic slenderness, section30 Suppression of radio and television interference 45 ratio, solidity ratio and spacing ratio 7

3 Design throat thickness of fillet welds 23Section five. Testing 4 Design throat thickness of deep-penetrCition31 General 46 fillet welds 23

5 Effective length with lateral bracing 25Section six. Instruction manual 6 Typical class E weld details 3232 General 48 7 Typical class F weld details .....:J.)

8 Typical class F and class G weld details 21Appendices 9 Typical class G weld details 36A Legislation and related documents 49

10 Angle of fleet 37B Text deleted 49C Derivation of design wind pressures 49

Index 62D The use of steels of higher tensile strengths than

those of steels complying with BS 4360 49

1

as 4466 : 1989

Contents

as 4465 : 1989Specification. Section one

Section one. General

1 Scope

This British Standard specifies requirements for the designand construction of hoists that are intended to be used astemporary installations during construction work. They areprimarily intended for the carriage of personnel but mayalso carry materials. The hoist cage is restrained againstlateral movement by a guide or guides and is suspended orsupported by either steel wire ropes or a rack and pinion(s).The maximum speed of travel of the hoist cage is 2 m/s.NOTE. The titles of the publications referred to in this standard arelisted on the inside back cover.

2 Definitions

For the purposes of this British Standard the followingdefinitions apply.

2.1 in service. A condition when the cage(s) is in anyposition other than at the lowest landing position of itstravel (whether it is laden or unladen). and when thecage(s) is at the lowest landing position and laden.

2.2 text deleted

2.3 mast. A structure that supports and guides the cage(and the counterweight when provided) outside of the maststructure.

2.4 out of service. A condition when the cage(s) is at thelowest landing position and unladen.

2.5 passenger. Any person, including the driver, transportedby a hoist.

2.6 progressive safety gear. A safety gear in which decelera-tion is effected by a braking action, and for which specialprovisions are made so as to limit the forces on the sus-pended part to a permissible value.

2.7 rated load. The load for which the equipment has beenbuilt and for which normal operation is guaranteed by thevendor.

2.8 rated speed. The speed of the hoist cage for which theequipment has been built and for which normal operationis guaranteed by the vendor.

2.9 safety gear. A mechanical device for stopping andmaintaining stationary on the guides the hoist cage orcounterweight in the case of overspeeding in the downwarddirection.

2.10 stopping distance. The distance the cage will fallduring a safety gear test, measured from the point ofrelease of the stationary cage to the point of arrest.

2.11 terminal stopping switch. A switch or combination ofswitches arranged to bring the cage to rest automaticallyat or near a terminal landing, independently of the func-tioning of the operating control device.

2.12 tower. A structure that supports and guides the cage(and the counterweight when provided) within the towerstructure.

2.13 ultimate limit switch. An emergency switch arrangedto stop the hoist automatically, in the event of the cagetravelling a predetermined distance beyond a terminallanding.

3 Design considerations

3.1 Design features

All components shall be correctly designed and of soundconstruction using materials that are free from patentdefects and that are of adequate strength and suitablequality. The construction and reliability of the equipment,in whole or part, shall be appropriate to its intended use,operating environment and design life.

Materials used in the construction of the hoist shall notsupport combustion.

3.2 Accessibility

The hoist shall be designed, constructed and installed insuch a manner that periodic examination, testing, mainte-nance or repairs may be readily and safely carried out.

2

Tab!e1. Listof loads

I --Symbol Oescription of load

L1 Loads due to static components, e.g. masts,ties and other appendages

L2 Loads due to moving components, e.g. cage,counterweight, ropes, moving cables

L3 Rated load

L4 (L2 + L3) x impact factor

Ls (L2 x impact factor) + (L3 x impactfactor x load spectrum factor)

I L6 Load due to in-service wind acting horizontallyII in any direction on the mast or tower, cage and

auxiliary items when applicable

L7 Load due to out-of-service wind actinghorizontally in any direction on the mast ortower, cage and auxiliary items whenapplicable

Table 2. Load combinations (see 5.3)

(1) Hoist in use without wind L 1 + L4(2) Hoist in use with in-service wind L1+L4+L6(3) Hoist in out-of-service condition L1 + L2 + L7(4) Hoist being erected or dismantled L1 + L4 + L6(5) Hoist cage in collision with overrun L1+L4+L6

buffers(6) Hoist with application of safety gear L1 + L4 + L6(7) Fatigue check (for each member in L1+Ls+L6

which fluctuating stresses occurwhen tested in accordance withclause 9)

Table 3. Impact facton

Rope suspended masses 1.25Progressive safety gear application 1.40Rack and pinion suspended masses 1.40Collision with resilient buffers:

(a) rope suspended cages 2.0(b) rack and pinion supported cages see note

NOTE. Take into account the kinetic energy of the driveunit when calculating the impact factor. Such factors canbe in excess of 10.

BS 4465 : 1989Section two

Section two. Structural design and construction

4 Loads and load combinations

4.1 Loads and load combinations to be considered in d~sign

4.1.1 General. The structure as a whole and each part of itincluding ties shall be designed to withstand the loads listedin table 1 in the combinations given in table 2.

iiiii!!!!!!iiiiiiiiii-iiiii!!!!!!

*(f)

*

4.1.2 Impact factor. In calculating live loads in members ofthe structure, forces due to moving masses, inertia forcesand shock shall be multiplied by an impact factor (seetable 1). The appropriate impact factor shall be as given intable 3.

4.1.3 Load spectrum factor. The load spectrum factors Kprequired to take account of the state of loading of the hoistthroughout its lifetime, as used in the treatment for fatiguedesign as specified in clause 9, shall be as follows:

(a) masses of constant magnitude, e.g. cages, 1.0

(b) masses of variable magnitude, e.g. payload, 0.6

4.1.4 Wind loads

4.1.4.1 Wind action. It shall be assumed that the wind canblow horizontally from any direction at a constant velocity,and that there is a static reaction to the loadings it appliesto a hoist structure.

4.1.4.2 Wind pressure. The dynamic wind pressure shall becalculated from

q =0.613V.2

whereq is the dynamic pressure (ill N/m2);

V. is the design wind speed (in m/s).

Aconversion chart covering V. in knots, mile/h and mis,and q in Ib/ft2, 1\1.':-..2and kgf/m2 is given in figure 1.

4.1.4.3 Design wind conditions. Two design wind condi-tions shall be taken into account in calculating wind loadson hoists, as follows.

(a) In-service wind. This is the wind pressure, irrespective

of height, in which the hoist is designed to operate.The wind loadings, which shall be assumed to be appliedin the least favourable direction in combination with theappropriate service loads specified in 4.1.1, shall be notless than the pressures specified in table 4.(b) Out-of-service wind. This is the wind pressure that a

hoist is designed to withstand when in an out-of-servicecondition.

For hoists used in the UK, the out-of-service windpressures specified in table 4 shall be used as the basisof design.

4.1.4.4 Wind load calculations. For mc~t complete andpart structures, and individual members used in hoiststructures, the wind load shall be calculated from:

F =AqCf

where

F is the wind load (in N);

A is the effective frontal area of the part underconsideration, i.e. the shadow area of its solid partsprojected onto a plane perpendicular to the winddirection (in m2);

q is the wind pressure corresponding to appropriatedesign condition (in N/m2);

Cf is the force coefficient in the direction of the wind,for the part under consideration.

3

Table 4. Design wind pressures

Height Wind pressure

In-service* Out-of-service*

All zonest Zone 1t Zone 2t Zone 3t Zone 4t

N/m2 N/m2 N/m2 N/m2 N/m2

Parts of hoist under 30 m from ground level 250 731 1167 1370 1588

Parts of hoist over 30 m and up to 60 m 250 868 1384 1625 1884from ground level





*See appendix C for details of the in-serviceand out-of-servicewind speeds and the methods used to calculate the design pressures.tZone 1: Greater London.Zone 2: Remainder of England and most of Walesand the southern half of Northern Ireland (see also zone 3).Zone 3: Lowlands of Scotland, the extreme south-western tip of Walesand most of the northern half of Northern Ireland(see also zone 41-Zone 4: Highlandsand Islands of Scotland and the extreme northern tip of Northern Ireland.


NOTE. It is acceptable for A and Cf for specific designs to bedetermined by full scale experimental testing.

The total wind load on the structure shall be taken as thesum of the loads on its component parts.

In calculating wind moment for out-of-service conditions,either:

(a) the wind pressure at the top shall be taken as

constant over the entire height of the structure; or(b) the structure shall be divided into the horizontal

zones of assumed constant pressure given in table 4 andthe appropriate value used for each zone.

4.1.4.5 Individual members, single lattice frames, etc: forcecoefficients. Force coefficients for individual members,single lattice frames, machinery houses, cages, etc. shall beas given in table 5.NOTE. The values for individual members vary according to theaerodynamic slenderness and, in the case of large box sections,with the section ratio. Aerodynamic slenderness and section ratioare defined in figure 2.

Where a frame is made up of flat-sided and circular sections,or of circular sections in both flow regimes (DVs < 6 m2 Is

and DVs ~ 6 m2 Is where D is the diameter of the section inmetres) the appropriate force coefficients shall be appliedto the corresponding frontal areas.

4.1.4.6 Multiple members, multiple frames, etc: shieldingfactors. Where parallel frames or members are positioned sothat the windward parts have a shielding effect on thosebehind them, the wind load on the unsheltered parts shallbe calculated from the formula given in 4.1.4.4, taking A asthe area in square metres of the windward frame or memberplus the unsheltered parts of those behind it. The wind loadon sheltered parts shall be calculated from:

Fs =AsqCfcf>

whereq and Cf are as defined in 4.1.4.4;

Fs is the wind load on the sheltered parts (in N);

As is the area of the sheltered parts under consideration(in m2);

cf> is the shielding factor given in table 6 according to thesolidity ratio of the front frame and the spacingratio; these ratios are defined in figure 2.

4

Table 5. Force coefficients Cf

Type Description Aerodynamic slendern_l/b or I/D.

5 10 20 30 40 50

Individual Rolled sections, rectangular hollow sections, 1.3 1.35 1.6 1.65 1.7 1.8members flat plates, fabricated box sections with

band D not greater than 0.5 m

Sectionratiob/d*

Fabricated box sections with b or d ~2 1.55 1.75 1.95 2.1 2.2greater than 0.5 m 1 1.40 1.55 1.75 1.85 1.9

0.5 1.0 1.2 1.3 1.35 1.40.25 0.8 0.9 0.9 1.0 1.0

Circular sections:where DV. < 6 m2/s 0.75 0.80 0.90 0.95 1.0 1.1where DVs ~6m2/s 0.60 0.65 0.70 0.70 0.75 0.8

Flat-sided sections 1.7Singlelattice Circular sections:frames where DVs < 6 m2/s 1.2

where DV. ~6m2Is 0.8

Cages Rectangular clad structures 1.0andcounter-weights,etc.

.See figure 2.

Table 6. Shielding factors IjJ

Specing Solidity ratio. A/A.ratio.Bib 0.1 0.2 0.3 0.4 0.5 .. 0.6

0.5 0.75 0.4 0.32 0.21 0.15 0.11.0 0.92 0.75 0.59 0.43 0.25 0.12.0 0.95 0.8 0.63 0.5 0.33 0.24.0 1 0.88 0.76 0.66 0.55 0.455.0 1 0.95 0.88 0.81 0.75 0.686.0 1 1 1 1 1 1

.See figure2.

iiii!!!!!!iiiiiiii-iiii!!!!!!

*[J)

*

4.1.4.7 Latticetowersofsquarecrosssection. In calculatingthe 'face-on' wind load on square towers, the solid area ofthe windward face shall be multiplied by the followingoverall force coefficients:

for towers composed of flat-sided sections 1.7q (1 + 1jJ)

for towers composed of circular sections

whereDV.<6m2/s 1.2q(1+1jJ)

where DV. ~ 6 m2/s 1.4q

The value of IjJshall be taken from table 6 for a/b = 1according to the solidity ratio of the windward face.

The maximum wind load on a square tower, which occurswhen the wind blows on to a corner, shall be taken as1.2 times the face-on, load.

4.2 Loads due to climatic conditions and naturalphenomena

For conditions of service outside the UK, loads due to wind,snow and temperature variation shall be taken into accountas appropriate.NOTE 1. These should be the subject of agreement between thepurchaser and the manufacturer.


NOTE 2. Attention is drawn to the fact that the laws or require-ments of a country may require the inclusion of earthquake forces.Such fo.rces should be determined in accordance with those require-ments end included in the loads to be considered in design.

5

knotso 5 10 15 20 25 30 35 40 1.5 50 55 60 65 70 75 80 85 90 95 100 105 1101 ... .. .. .. 1 .. .. I . .. . 1 .. . .. . .. . 1 .. . .. . . .. I .. .. I . .. .1. .. . I ... . I .. .. I .. .. I .. .. I .. .. I .. . .. . .. .1. .. . I . .. . I . . . .. .. .. 1

mile/ho 5 10 15 20 25 30 35 40 1.5 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 1301111111...1111111111111111111111111111111.11111111111111,111111111111.111111 111111.1111111111111111111111111111111111III,IIIul

m/s

o


Veloc i ty V

Dynamic qpressure

1,1 I I

IbfldoIN/m2oIkgf 1m2o

10I I

15 20I I t I I I

1I

I.I 5I

6 7 8 9 10I 1 I I I

2I

3I

25 30I . 40

I I50

I60

I I5535

I I

1.5I I I I . I I. I I I I

15I I I I I

20 25 30 35 40I I I I I I I I I. I I I I... I1IIIII

50I

100150

200I I I

300 400 500 600 700 800 9001000 1200I I I I I I I I I I I I I I I . I

2000lIfo .16~ .18fO

I 1

10 15 20 255

Figure 1. Conversion chart for wind speed and pressure

5 Selection of steel, minimum thicknessand working stresses

5.1 Selection of steel

5.1.1 Steel shall be selected from either:(a) structural steels complying with BS 4360; or(b) other steels, provided that the hoist manufacturer

shows that they have comparable properties to steelscomplying with BS 4360 and they have been subjectedto equivalent tests.

5.1.2 Where thicknesses of steel are specified that exceedthe maximum values given in BS 4360 for Charpy V-notchimpact tests, the impact value derived from standard testpieces shall be not less than that given in BS 4360 for thetype of steel under consideration on the standard test piece.

5.1.3 Where hoists are to be used at low temperatures suchthat brittle fracture might occur, the material used for load-bearing members shall have specified low temperatureimpact properties, adequate to meet the service conditionsinherent in the design.

5.1.4 For temperate or tropical conditions, steels having nospecified impact properties are acceptable, with the excep-tion of the following, which shall not be used unless impactor other tests show that the material is suitable for service:

(a) plates and sections above 30 mm thickness wherebrittle fracture might occur under tension loads;(b) plates and sections above 25 mm thickness wherebrittle fracture under tension loads would result in majorstructural collapse.

NOTE. For further information regarding selection of steels tocounter brittle fracture see chapter 2 of BS 449 : Part 2 : 1969.

5.2 Minimum thickness of plates and sections

The proportioning of members of hoist structures shallfollow from consideration of the stresses engendered byservice conditions, and shall have regard to other practicalconsiderations including the requirements of manufacturingprocesses, vulnerability to accidental damage, the incidenceof corrosion in relation to protective coatings used, etc.NOTE. This standard does not impose minimum thicknesses.Attention is drawn to the requirements laid down in BS 4395 forthe thicknesses of members at joints made with high strength frictiongrip bolts.

5.3 Permissible working stresses

The calculated stresses in each part of the structure due tothe load combinations listed in table 2 shall not exceed anyof the following.

(a) Under load combination (1). The basic stress

multiplied by the duty factor 0.95.(b) Under load combination (2). The basic stress

multiplied by the duty factor 1.07.

(c) Under load combination (7). The permissible fatigue

stress.(d) Under separate load combinations (3), (4), (5)

and (6). The basic stress multiplied by the duty factor1.36.

6

as 4465 : 1989Section two

~

Wind

length of member 1 1Aerodynamic slenderness = K - or -breadth of section across wind front b D

Section ratio(for box sections)

breadth of section across wind front- depth of section parallel to wind flow

b=-d

(a) Aerodynamic slenderness and section ratio

iiiii!!!!!!!!!iiiiiiiiii

*(/)

*

b

-iiiii!!!!!!!!!

ASolidity ratio -A.area of solid parts (shown shaded)

enclosed area:tAmember.

b X 1

(b) Solidity ratio

distance between facing sides 8Spacing ratio =

breadth of member across wind front b

(c) Spacing ratio

Figure 2. Definitions: aerodynamic slenderness, section ratio, solidity ratio and spacing ratio

7


6 Stresses in structural components

6.1 Individual members, rolled sections, hollow sectionsand members with plated webs: verification relative to theyield stress

6.1.1 Basic stresses. Basic stresses for steels complying withBS 4360 for use in the application of this standard shallcomply with 6.1.2 to 6.1.8.NOTE 1. In general, the basic stress is expressed as a proportionof the yield stress of the grade of steel under consideration.The formulae for deriving basic stresses and tabulated values areboth given.

NOTE 2. Members subjected to secondary stresses. Relaxations insome of the requirements of 6.1.2 to 6.1.8 are allowed in caseswhere secondary stresses are calculated and taken into account inthe design (see 6.3).

If steels with higher tensile strengths than those of BS 4360steels are used, the specific' requirements of appendix Dshall be met.

6.1.2 Members subject to simple axial tension (see 5.3).The basic tensile stress Pat,bas (in N/mm2) shall not exceedthe value

Pat,bas (on net section) =0.6Yswhere

Ys is the yield stress of the steel under consideration(in N/mm2).

Tabulated values of Pat,baSfor the range of steels covered byBS 4360 are given in table 7.

The maximum widths of tension flange plates with stiffenedor unstiffened edges are specified in 8.2.3.

6.1.3 Members subject to simple axial compression(see 5.3). The basic compressive stress Pac bas shall notexceed Pat bas as defined in 6.1.2 or the v~lue (in N/mm2)obtained from

Pac,bas = 0.6F crip

where

Fcrlp is the applied stress at failure of a member(in N/mm2)

subjected to overall flexural buckling due to axial compres-sion as given by the equation:

F. = Ys+(71+1)Co _

J{(YS+(1I+1)CO )2

- Y.C }cnp2 2 s 0

where

Co is the Euler critical stress

Ys is the yield stress of the steel under consideration;for sections fabricated from plate by welding,the yield stress Ys is reduced by 25 N/mm2 .

NOTE. This provision need not be applied to welded compoundroiled sections or to rolled sections with welded flange cover plates.

E is Young's modulus (= 205 000 N/mm2);

71 is the Perry coefficient (= a:(s - so) X 10-3, but notless than zero),

a: is the Robertson constant from table 8;

s is the slenderness ratio (= lIr);

So is the limiting slenderness ratio for stub columns(= 0.2."yEIYs);

r is the radius of gyration about the appropriate axis;

is the effective length relative to the same axis,as defined in 8.1.

Tabulated values of Fcrip for the range of steels covered byBS 4360 are given in table 9 for the values of a: given intable 8.

For slenderness ratio less than so, Fcrip = YS'

The effective and maximum widths of plates in compres-sion are specified in 8.2.1 and 8.2.2 respectively.

The slenderness ratio s for any strut shall be obtained bydividing its effective length 1 as given in 8.1 by the minimumradius of gyration r of any cross section within the middlethird of the length. Where the end fixing conditions of thestrut in the X and Y planes are different, its effective lengthsin these planes will also differ.

6.1.4 Members subject to bending (see 5.3)

6.1.4.1 Areas in tension. The basic tensile bending stressPbt,bas (in N/mm2) shall not exceed the following values:for plates, flats, tubes, rounds,

)square and similar sections Pbt,bas= 0.65Ysbending about their minor axis;

for rolled beams, channelsangles and tees, and for plategirders with single or multiplewebs with:

d1 It not greater than 85 forsteel of grade 43; Pbt,bas = 0.62Ysddt not greater than 75 forsteel of grade 50;d1 It not greater than 65 forsteel of grade 55;

for plate girders with singleor multiple webs with:

d1 It greater than 85 for steelof grade 43; Pbt,bas =0.59Ysd1 It greater than 75 for steelof grade 50;ddt greater than 65 for steelof grade 55;

where

Ys is as defined in 6.1.2 and d1 and t are as defined intable 7 for parts in bending. Tabulated values ofPbt,bas for the range of steels covered by BS 4360are given in table 7.

The maximum widths of tension flange plates with stiffenedor unstiffened edges are specified in 8.2.3.

6.1.4.2 Areas in compression

6.1.4.2.1 Maximum widths of plates. The maximum widthsof plates in compression shall be as specified in 8.2.2.

8

iiiii!!!!!!iiiiiiiiii-iiiii!!!!!!

*(J)

*

e..cE.E

..o...

r:o

I

toE-E~Z N

toEE 10

z~toE-E!8Z ...

toEE ,...~Z ...

toE-E~Z ...

II).-N

toEE (I)

-NZ ...

~.-ai..!'"f'"e: a;

o e:0;; 0c .~.. u.. ma; ..'x >ta 'fi.: ~

'"...

r ~~ 0

toEE 0,...

Z N

toE-EiZ N

toEE 0~

Z N

toEE M- .-Z N

c;.-ai..!

e: e:.~ .gf U

0. mE ::o eU 01a; ..'x >«I °ze: ..

'":::

rGO

'"e:

a.. 0

o,...N

o~N

M...N

...

...

(I)N...

M(I)N

XI Ee: ~

~'"U ...- .r:.r:..

:;; II"'Ee: ._.- ..ii,E.r:",'" .-.. .... ...o!!!o0.",..~~

'"Ol-e: 0.o .... ::J" '"~ 5.. ..

~ ..o.r:.r:"eO...

'"".r:.r:..~o...:..:~:I ..".r:=..~o.: E... ~o

'".~~- ..

cocoN

oQON

....coN

o....N

ocoN

coMN

...MN

oNN

...NN

......N o

N

......N

NQO...

oco.-

o10...

o~...

--

III'..'";:~t.2~¥0...... ...oo!!!:::'f'" .-- '"

9

....co...

...

...M...

coN...

oN...

~o...

...(I)

oQO

-o"''tI.. e:- ::- ..Ol-e: 01o e:..

'"U ... .."'0;~ ~'fi2.. U::: vi.. E::

'"o ..0

~i.r:-.. -oe: ..o

":: ~f-Et;'6J_

10:;--:

~iilD..-..CIIoZl!tn-GO.o",> .. ..«~~

'"e:'Q.'tIe:

'"....iC'"iIe;;:

,§ ~'" 1:.. ::J.0 ...= 1;r ;;::

'"e:

a.. 0


ocoM

NMM

oNM

N....N

ocoN

co(I)...

N.......

cqpo

ai

!

~~'"......r:o-s.~~~:c w-E aio GO

~ !'" '".. ..~ ~..o ..... ..'tI e:~ ..~ ~

'E '5

~ it: .~'"

<1\a.. ID

coQOM

...

..'tIe:::J..e:o';::'5e:oUCII.S'tI'"~...r:..g

'tIe:o0...e...oU..'".r:..

Miii.:e:~'0,

'"5..c: Uo .:!.~ c»'"

.r:'0 ..e-~J!J.: ~>ii.Q 0..

i :;e: E'B 1!.0 0o ....

'".0'">.r:

'" ::E ~:: ..~ UfA 'i'tI .00; ..'> .i'0 Q... 0~ !i~ i~ .s<1\

~ ~~ ;.5 .~g ~g> ~

'5 .!!e: .0o 'wQ. .!!f E8 !.; ~.. ..f e:... 'm'"

..U .0

'C;; 0 c'"

0 0ID 1-';::...- NtW W'tII- I- ';;;o 0 e:Z Z 8

oMM

co...M

NoM

ocoN

8N

..:c'='E.....0...-s..m..eU..

'tI.r:U:c~2U

.:!..-S..::J.0....ar;"...............e:..j'5iU.;;;

'".0...r:..o..>ii0.'"...oc:.g....e....'"e:~5~..:c.;;;

'"'§..0...-s....'"eU.:g'tIe:~.r:.~.r:~

Miii >-e:ii.- 0... ..2 t.M.g.. ::.r: ..I-~

."M'"W .:

b~Z ~

Table 8. Values of Robertson constant Q for strutsof various sections

Type of section Thickness of Axis of aflange or plate buckling

Rolled I section xx 2.0(universal beams, UBI yy 3.5

Rolled H section Up to 40 mm xx 3.5(universal columns, yy 5.5UC) (see note 1) Over 40 mm xx 5.5

yy 8.0

Welded plate I or H Upt040mm xx 3.5sections yy 5.5(see notes 1, 2 and 3) Over 40 mm xx 3.5

yy 8.0

Rolled I or H sections xx 3.5with welded flange yy 2.0cover plates(see notes 1 and 4)

Welded box sections Up to 40 mm Any 3.5(see notes 1, 3 and 5) Over 40 mm Any 5.5

Rolled channel Any 5.5sections, rolled anglesections and T-bars(rolled or cut fromUB or UC)

Hot-rolled structural Any 2.0hollow sections

Rounds, square and Up to 40 mm Any 3.5flat bars Over 40 mm Any 5.5(see note 1)

Compound rolled Any 5.5sections (two or moreI, H or channelsections, I sectionplus channel, etc.).

Two rolled angle, Any 5.5channel or tee sectionsback-to-back

Two rolled sections Any 5.5laced or battened

Composite members Any 2.0of closed latti ceconstruction

NOTE 1. For thicknesses between 40 mm and 50 mm the value ofFcrip may be taken as the average of the value for thicknesses lessthan 40 mm and the value for thicknesses greater than 40 mm.NOTE 2. For welded plate lor H sections where it can beguaranteed that the edges of the flanges will only be flama-cut,a = 3.5 may be used for buckling about the y-y axis for flanges upto 40 mm thick and a = 5.5 for flanges over 40 mm thick.NOTE 3. Yield strength for sections fabricated from plate by weld-ing reduced by 25 N/mm2.

NOTE 4. To qualify under the category 'rolled I or H section withwelded flange cover plates' the widths of the flange and the platehave to be within the greater of 25 mm or 25 % of the larger width.If the smaller width is less than 25 % of the larger, the category'welded plate I or H sections' shall apply, otherwise the categoryshall be taken as 'rolled I section' or 'rolled H section' as appro-priate.NOTE 5. 'Welded box sections' include those fabricated from fourplates, two angles or an I or H section and two plates but not boxsections composed of two channels or plates with welded longi-tudinal stiffeners.

BS 4465 : 19B9Section two

6.1.4.2.2 For sectional shapes with I y equal to or greaterthan Ix. Where

Iy is the moment of inertia of the whole section aboutthe axis lying in the plane of bending (the y-y axis), and

Ix is the moment of inertia of the whole section aboutthe axis normal to the plane of bending (the x-x axis),

the basic compressive bending stress shall not exceed thevalue of Pbt,b8Sgiven in 6.1.4.1.

6.1.4.2.3 For sectional shapes with I y smaller than Ix.

6.1.4.2.3.1 Where Iy and Ix are as defined in 6.1.4.2.2,the basic compressive bending stress Pbc bes shall notexceed Pbt,bes as defined in 6.1.4.1, or the value of Pbc,ba.corresponding to C., the critical stress in the compressionelement (in N/mm2) calculated as set out in 6.1.4.2.3.2and 6.1.4.2.3.3.

6.1.4.2.3.2 For sections with a single web, including Isections with stiffened or un stiffened edges, channels,angles, tees, etc., but excluding I sections where the thi.ck-ness of one flange is more than 3 times the thickness of theother flange, the critical stress Cs shall be calculated asfollows.

(a) Where the flanges have equal moments of inertia

about the y-y axis

C. = (1644 ~yr j{1 +2~ (,~~)

2} =A

except that the value of C. shall be increased by 20 % forrolled beams, channels, and plate girders provided that:

Tit is not greater than 2;

ddt is not greater than 85, for steel of grade 43complying with as 4360;

d1 It is not greater than 75, for steel of grade 50complying with as 4360;

d1 It is not greater than 65, for steel of grade 55complying with as 4360;

whereis the effective length of the compression flange(see 8.1.3);

ry is the radius of gyration about the y-y axis of thegross section of the member, at the point ofmaximum bending moment;

D is the overall depth of member, at the point ofmaximum bending moment;

T is the effective thickness of the compressionflange; i.e. K 1 X mean thickness of the horizontalportion of the compression flange at the pointof maximum bending moment.NOTE. For rolled sections, T = K 1 X thickness given inreference books. The coefficient K 1 makes allowance forreduction in thickness or breadth of flanges betweenpoints of effective lateral restraint and depends on N,the ratio of the total area of both flanges at the point ofleast bending moment to the corresponding area at thepoint of greatest bending moment between such pointsof restraint.

d1 and t are as defined in table 7 for parts in bending.

Flanges shall not be reduced in breadth to give a valueof N lower than 0.25.

10

Table 9. Values of Fcrlp for steels complying with as 4360

S'endern_ ratio l/r Grade 43 It.., with a yie'd Grade 60 Iteel with a yield Grlde 66 lteel with a yieldItr_ in N/mm2 of: str_ in N/mm2 of: str_ in N/mm2 of:

215 230 245 280 325 340 355 400 415 430 450

Limiting l'end_nISI ratio,o below which Fcrlp - Y.

19 19 18 17 16 15 15 14 14 14 13

(al Q - 2.0 (see 6.1.31 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2

'0 215 230 245 280 325 340 355 400 415 430 45020 213 228 243 277 322 337 350 394 409 424 44430 208 223 237 271 314 329 342 385 399 413 43240 203 217 231 264 305 319 331 372 386 399 41750 197 210 224 254 293 306 317 354 366 378 39460 190 202 214 242 276 288 297 327 337 346 35870 180 191 202 226 253 262 268 290 296 302 31080 168 178 186 205 225 230 234 248 251 255 25990 155 162 168 181 194 198 200 208 210 212 215

100 139 145 149 158 166 169 170 175 176 178 179110 124 128 131 137 143 144 145 148 149 150 151120 110 112 115 119 123 124 124 127 127 128 129130 97 99 101 104 106 107 108 109 110 110 111140 86 87 89 91 93 93 94 95 95 96 96150 77 78 79 80 82 82 83 83 84 84 84160 68 69 70 71 72 73 73 74 74 74 74170 61 62 63 64 65 65 65 66 66 66 66180 55 56 56 57 58 58 58 59 59 59 59190 50 51 51 52 52 52 53 53 53 53 53200 46 46 46 47 47 48 48 48 48 48 48210 42 42 42 43 43 43 43 44 44 44 44220 38 38 39 39 39 40 40 40 40 40 40230 35 35 35 36 36 36 36 37 37 37 37240 32 33 33 33 33 33 33 34 34 34 34(bl Q - 3.5 (see 6.1.31

'0 215 230 245 280 325 340 355 400 415 430 45020 211 226 241 275 320 334 346 390 405 419 43930 204 218 232 265 307 321 332 374 388 402 42040 195 209 222 253 292 305 316 354 367 380 39650 186 198 211 239 275 286 295 329 340 351 36560 175 186 198 223 253 263 270 297 306 314 32570 163 173 183 203 228 235 241 260 266 272 27980 150 158 166 182 201 206 210 223 227 231 23590 136 143 149 161 174 178 181 190 192 195 197

100 123 128 132 141 151 153 155 161 163 164 166110 110 113 117 124 130 132 133 138 139 140 141120 98 101 103 108 113 114 115 118 119 120 121130 87 89 91 95 99 100 100 103 104 104 105140 78 79 81 84 87 88 88 90 90 91 92150 70 71 72 75 77 77 78 79 80 80 81160 63 64 65 67 68 69 69 70 71 71 71170 57 57 58 60 61 62 62 63 63 63 64180 51 52 53 54 55 55 56 56 57 57 57190 47 47 48 49 50 50 50 51 51 51 52200 43 43 44 44 45 46 46 46 46 47 47210 39 39 40 41 41 42 42 42 42 42 43220 36 36 37 37 38 38 38 39 39 39 39230 33 33 34 34 35 35 35 35 36 36 36240 . 31 31 31 32 32 32 32 33 33 33 33

iiiiii!!!!!!!!!iiiiiiiiiiii-iiiiii!!!!!!!!!

*(f)

*


11

Table 9 (concluded)

Slenderness ratio 11r Grade 43 ,teel with a yield Grade 50 Iteel with a yield Grade 55 Iteel with a yieldItr_ in N/mm2 of: Itr_ in N/mm2 of: Itr_ in N/mm2 of:

215 230 245 280 325 340 355 400 416 430 450

Limiting,lendern_ ratio,o below which Ferlp m Y,

19 19 18 17 16 16 15 14 14 14 13

(e) Q = 5.5 (see6.1.3) N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2

'0 215 230 245 280 325 340 355 400 415 430 45020 210 224 239 273 317 331 342 385 399 414 43330 198 211 225 257 298 311 321 361 374 387 405

40 186 198 211 240 277 289 298 334 345 357 37350 173 185 196 222 254 265 272 303 313 322 33560 160 170 180 202 230 238 244 268 276 283 293

70 147 155 164 182 204 211 215 233 239 244 25180 133 140 147 162 179 184 187 200 204 208 21390 120 126 131 143 156 159 162 171 174 177 180

100 108 112 117 126 135 138 140 147 149 150 153110 96 100 104 111 118 120 121 126 128 129 131120 86 89 92 97 103 105 106 109 111 112 113

130 77 80 82 86 91 92 93 96 96 97 98140 69 71 73 77 80 81 82 84 85 85 86150 63 64 66 68 71 72 73 74 75 76 76

160 57 58 59 61 64 64 65 66 67 67 68170 51 52 53 55 57 58 58 59 60 60 61180 47 48 49 50 52 52 53 54 54 54 55

190 43 44 44 46 47 47 48 49 49 49 49200 39 40 40 42 43 43 43 44 44 45 45210 36 37 37 38 39 39 40 40 41 41 41

220 33 34 34 35 36 36 36 37 37 37 37230 31 31 32 32 33 33 34 34 34 34 34240 29 29 29 30 31 31 31 31 32 32 32

(d) Q =8.0 (see6.1.3)

'0 215 230 245 280 325 340 355 400 415 430 45020 207 222 236 270 313 327 336 378 393 407 42630 191 204 217 248 287 300 308 345 358 371 388

40 175 187 199 226 261 272 279 312 323 334 34850 160 170 181 204 234 244 249 277 286 295 30660 145 154 163 183 208 215 220 242 249 255 264

70 131 139 146 163 182 189 192 209 214 219 22580 118 124 130 144 159 164 167 179 183 187 19190 106 111 116 127 139 142 145 154 157 160 163

100 95 99 103 112 121 124 126 133 135 137 139110 85 88 92 99 106 108 110 115 117 118 120120 76 79 82 87 93 95 96 100 102 103 104

130 68 71 73 78 82 84 85 88 89 90 91140 62 64 66 69 73 74 75 78 79 80 80150 56 58 59 62 66 66 67 69 70 71 71

160 51 52 54 56 59 60 60 62 63 63 64170 46 47 49 51 53 54 54 56 56 57 57180 42 43 44 46 48 49 49 50 51 51 52

190 39 40 41 42 44 44 45 46 45 46 47200 36 37 37 39 40 40 41 42 42 42 43210 33 34 34 36 37 37 37 38 39 39 39

220 31 31 32 33 34 34 34 35 35 36 36230 28 29 29 30 31 32 32 32 33 33 33240 26 27 27 28 29 29 29 30 30 30 31


12

Table 10. Values of K1

N 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0

Kl 1.0 1.0 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2

Table 11. Values of K2

M 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0

K2 0.5 0.4 0.3 0.2 0.1 0.0 -0.2 -0.4 -0.6 -0.8 -1.0

Values of K 1 for different values of N are given intable 10.

Where the value of N calculated for the compressionflange alone is smaller than that when both flanges arecombined, this smaller value of N shall be used.

(b) Where the moment of inertia of the compressionflange about the y-y axis exceeds that of the tensionflange

C.= ~644 :Vrjf1+ 2~C:D)2} +K2~644 ;vY

= A + K2Bwhere

I, rv and D are as defined in (a);

T is the effective thickness of flange;Le. K 1 X mean thickness ofthe horizontal portionof the flange of greater moment of inertia aboutthe y-y axis of the member at the point ofmaximum bending moment, where K 1 is obtainedfrom table 10;

K2 is a coefficient to allow for inequality of tensionand compression flanges, and depends on M,the ratio of the moment of inertia of the com-pression flange alone to that of the sum of themoments of inertia of the compression andtension flanges, each calculated about its ownaxis parallel to the y-y axis of the member, at thepoint of maximum bending moment.

NOTE. For flanges of equal moment of inertia M .. 0.5 andK2 .. O. For tees and angles M = 1.0 and K2 .. 0.5.Values of K2 for different valuesof M are givenintable 11.(c) Where the moment of inertia of the tension flange

about the y-y axis exceeds that of the compression flange

C. = [(1644 ;,)' jh~ (:.:) '1+

*(f)

*

+ K'~644 ;,) ']~:

where

I, rv and D are as defined in (a);

T and K2 are as defined in (b);

Yc is the distance from the neutral axis of girder toextreme fibre in compression;

Yt is the distance from the neutral axis of girder toextreme fibre in tension.


Valuesof K2 for different values of M are given intable 11.NOTE. For tees and angles. M - 0 and K2 - -1.

Table 12 gives values of A and 8 for different ratios ofl/r and D/T to be used for calculating C. (in N/mm2).

Table 13 gives values of PbCp. for different values of C..

6.1.4.2.3.3 For sections other than those describedin 6.1.4.2.3.2:

(a) where the section is symmetrical about the x-x axis,

C. shall be calculated from the formula given in appen-dix E;(b) where the section is not symmetrical about the

x-x axis, C. shall be calculated using either:(1) the formula given in 6.1.4.2.3.2, which will give

conservative values; or(2) more precise methods.

6.1.5 Members subjected to shear (see 5.3)

6.1.5.1 Rolled beams, channels, angles and tees. The basicaverage shear stress Pq,b88 (in N/mm1) on the effectivesectional area shall not exceed the value

Pqp. = 0.37Y.where

Y. is as defined in 6.1.2.Tabulated values of Pqp. for the range of steels covered byBS 4360 are given in table 7.

6.1.5.2 Solid web plates. Solid web plates and stiffenersshall be proportioned in accordance with 8.3.

The basic average shear stress PqiJal (in N/mm2) on theeffective sectional area of a solid web shall not exceed thevalue given in 6.1.5.1 or that given by the followingequations.

For grade 43 steel complying with BS 4360

Pq,b88 = 91

[.3-

I

bl'

(b) 'IJ250 1 + % -

aFor grade 50 steel complying with BS 4360

pqP.=131 ['.3-

1

bl'

(b)'IJ

2001+%-a

For grade 55 steel complying with BS 4360

Pqp. = 167

['.3-

I

bl'

en]180 1 + % -a

13


wherea is the greater clear dimension of the web in a panel,

not greater than 270t;

b is the lesser clear dimension of the web in a panel,not greater than 1BOt;

t is the thickness of web.

Tabulated values of Pq,balfor stiffened webs for varyingratios of depth of panel d to thicltness of web t and variousspacings of stiffeners are given in table 14 for the range ofsteels covered by BS 4360. The depth of panel d is definedas follows.

For webs without horizontal stiffeners, d is the clear dis-tance between flange angles or, where there are no flangeangles, between flanges (ignoring fillets); where tongueplates having a thickness not less than twice the thicknessof the web plate are used, d is the depth of the girderbetween the flanges less the sum of the depths of the tongueplates or eight times the sum of the thicknesses of thetongue plates, whichever is the less.

For webs with horizontal stiffeners, d is the clear distancebetween the tension flange (angles or flange plate or tongueplate) and the horizontal stiffener.

6.1.6 Members subjected to bearing (see 5.3). The basicbearing stress Pb bal (in N/mm2) on flat surfaces and on theprojected area of fixed axles and pins shall not exceed thevalue

Pb,bal = O.BOY,where

Y. is as defined in 6.1.2.

Tabulated values of Pb,bal for the range of steels covered byBS 4360 are given in table 7.

6.1.7 Members subjected to a combination of stresses

6.1.7.1 Proportioning of members

6.1.7.1.1 Members subjected to a combination of coexis-tent bending and axial loads shall be designed in accordancewith 6.1.7.1.2 and 6.1.7.1.3; those subjected to a combina-tion of shear and other stresses shall be designed inaccordance with 6.1.7.1.4 and 6.1.7.1.5.

6.1.7.1.2 Members subjected to bending and axial compres-sion shall be so proportioned that

fac fbc-+- ~ 1Pac Pbc

where

fac is the calculated axial compressive stress;

Pac is the permissible compressive stress in axiallyloaded compression members (see 5.3 and 6.1.3);

fec is the calculated maximum compressive stress due tobending about both principal axes;

Pbc is the permissible compressive stress in bending,using the lesser value when bending occurs aboutboth axes (see 5.3 and 6.1.4).

6.1.7.1.3 Members subjected to bending and axial tensionshall be so proportioned that

fat fbt-+ - ~1Pat Pbt

where

fat is the calculated axial tensile stress;

Pat is the permissible tensile stress in axially loadedtension members (see 5.3 and 6.1.2);

fbt is the calculated maximum tensile stress due tobending about both principal axes;

Pbt is the permissible tensile stress in bending (see 5.3and 6.1.4).

6.1.7.1.4 Members subjected to shear and bending shall beso proportioned that the equivalent stress fa (in N/mm2)calculated from

fa = ..j(fb/ + 3fq2) or fromfa = ..j(fbc 2 + 3fq 2)

is not greater than Pa

wherefq is the calculated shear stress;

fbt and fbc are as defined in 6.1.7.1.3 and 6.1.7.1.2respectively;

Pa is the permissible equivalent stress (in N/mm2)(see 5.3 and 6.1.7.2).

6.1.7.1.5 Members subjected to shear, bearing and bending,shall be so proportioned that the equivalent stress fa(in N/mm2 ) calculated from

fa=..j(fbt2 +fb2 +fbtfb+3fq2)

or from

fa =..j(fbc2 +fb2 - fbcfb +3fq2)

is not greater than Pa

where

fb is the calculated bearing stress;fq, fbc, fbt and Pe are as defined in 6.1.7.1.4.

6.1.7.2 Basic equivalent stress. The basic equivalent stressPa,bes (in N/mm2) due to a combination of shear and otherstresses shall not exceed the value

Pa,bes = 0.93 Y.where

Y. is as defined in 6.1.2.

Tabulated values of Pa,besfor the range of steels covered byBS 4360 are given in table 7. (See also note 3 to table 7.)

6.1.8 Members with flanges subjected to transverse bendingstress. The design of members subjected to this type ofloading shall take into account both the longitudinal andtransverse bending stresses.NOTE. A suitable method is that given for the design of overheadrunway beams in as 2853.

14

Table 12. Values of A and 8 to be used for calculating values of C.

\ A (see notes 1 and 2)8

I/r\fIT (see8 10 12 14 16 18 20 2& 30 35 40 &0 60 80 100 note 31N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm225 5276 4954 4771 4656 458r 4528 4490 4431 4399 4379 4366 4351 4343 4335 4331 432430 3919 3616 3440 3330 3256 3205 3167 3109 3077 3058 3045 3030 3022 3014 3010 300335 3087 2802 2634 2528 2456 2406 2369 2312 2280 2261 2248 2233 2225 2217 2213 220640 2534 2266 2107 2005 1935 1886 1850' 1794 1763 1743 1731 1716 1708 1700 1696 168945 2145 1893 1742 1644 1577 1529 1494 1439 1408 1389 1376 1361 1353 1345 1341 133550 1858 1622 1478 1384 1319 1273 1239 1184 1154 1135 1123 1108 1100 1092 1088 108155 1639 1416 1279 1189 1127 1082 1049 996 966 947 935 920 912 904 900 89360 1466 1256 1126 1040 980 936 904 852 822 804 792 777 769 761 757 75165 1327 1129 1005 922 864 822 791 740 711 693 681 666 658 650 646 64070 1212 1025 907 827 772 731 700 651 622 604 592 578 570 562 558 55275 1116 938 826 750 696 657 627 579 550 533 521 507 499 491 487 48080 1034 865 758 685 633 595 567 519 492 474 463 449 441 433 429 42285 964 803 701 631 581 544 516 470 443 426 414 400 392 384 381 37490 903 750 652 584 536 501 473 428 402 385 374 360 352 344 340 33495 850 703 609 544 498 463 437 393 367 350 339 325 318 310 306 299100 802 662 572 509 464 431 405 363 337 321 310 296 288 281 277 270110 722 593 509 452 410 378 354 313 289 273 262 249 241 234 230 223120 657 537 460 406 366 337 314 275 252 237 226 213 206 198 194 188130 603 492 419 369 332 304 282 245 223 208 198 185 178 170 167 160140 557 453 385 338 303 277 256 221 199 185 175 163 156 148 144 138150 518 420 357 312 279 254 235 201 180 166 157 145 138 130 127 120160 484 392 332 290 259 235 216 184 164 151 142 130 123 116 112 106170 454 368 311 271 241 219 201 170 151 138 129 117 111 104 100 94180 428 346 292 254 226 204 187 158 140 127 118 107 100 93 90 83190 405 327 275 239 212 192 176 148 130 118 109 98 92 85 81 75200 384 310 261 226 201 181 166 138 121 110 101 91 84 77 74 68210 365 294 248 215 190 171 156 130 114 103 95 84 78 71 68 61220 348 280 236 204 181 163 148 123 107 96 89 78 72 66 62 56230 332 268 225 195 172 155 141 117 101 91 83 73 67 61 57 51240 318 256 215 186 164 148 134 111 96 86 79 69 63 57 53 47250 305 246 206 178 157 141 128 106 91 81 74 65 59 53 50 43260 293 236 198 171 151 135 123 101 87 78 71 61 56 49 46 40270 282 227 190 164 145 130 118 97 83 74 67 58 53 46 43 37280 272 219 183 158 139 125 113 93 80 71 64, 55 50 44 41 34290 262 211 177 152 134 128 109 89 77 68 61 53 47 41 38 32300 254 204 171 147 129 116 105 86 74 65 59 50 45 39 36 30

NOTE 1. The value of A is as follows.

r 2

{ 1 IT 2}A = (1644-L) V 1 + - (_)

I 20 ryD

NOTE 2. Where flanges are equal and of constant cross section C. = A.

NOTE 3. The value of 8 is as follows.

B= (1644 ~y)2

iiiii!!!!!!!iiiiiiiiii-iiiii!!!!!!!

*(I)

*


15

Table 13. Basic stress Pbc,b81 for different values of critical stress C. (see also table 7)

Cs Pbc,bas for steels complying with BS4360

Grade 43 steel with a yield Grade 50 steel with a yield Grade 55 steel with a yieldstress in N/mm2 of: stress in N/mm2 of: stress in N/mm2 of:

215 230 245 280 325 340 355 400 415 430 450

N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 Nlmm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2

20 11 11 11 11 11 11 11 11 11 11 1130 16 16 16 16 16 16 16 17 17 17 1740 20 21 21 21 22 22 22 22 22 22 2250 25 25 26 26 27 27 27 27 27 27 2760 29 30 30 31 31 32 32 32 32 32 33

70 34 34 35 35 36 36 37 37 37 38 3880 38 38 39 40 41 41 41 42 42 42 4390 41 42 43 44 46 46 46 47 47 47 48

100 45 46 47 48 50 50 51 52 52 52 53110 48 50 51 52 54 55 55 56 57 57 57

120 52 53 54 56 58 59 60 61 61 62 62130 55 56 57 60 63 63 64 65 66 66 67140 58 59 61 64 67 67 68 70 70 71 71150 60 62 64 67 70 71 72 74 75 75 76160 63 65 67 70 74 75 76 78 79 80 80

170 65 67 70 74 78 79 80 82 83 84 85180 67 70 72 77 81 82 83 86 87 88 89190 70 72 75 79 84 86 87 90 91 92 93200 71 74 77 82 88 89 90 94 95 96 97210 73 76 79 85 90 92 94 98 99 100 101

220 75 78 81 87 94 95 97 101 102 104 105230 77 80 83 90 96 98 100 105 106 107 109240 78 82 85 92 99 101 103 108 110 111 112250 80 83 87 94 102 104 106 111 113 114 116260 81 85 89 96 104 107 109 115 116 118 120

270 82 86 90 98 107 109 112 118 119 121 123280 84 88 92 101 110 113 115 122 124 126 128290 86 91 95 104 113 116 119 126 129 131 133300 88 93 97 106 116 120 123 130 133 135 138310 90 94 99 109 119 123 126 134 137 139 142

320 91 96 101 111 122 126 129 138 141 143 147330 93 98 103 113 125 129 132 141 144 147 151340 95 100 105 115 127 131 135 145 148 151 155350 96 101 106 117 130 134 138 148 151 154 158360 97 103 108 119 132 136 140 151 155 158 162


16

Table 13 (concluded)

c. Pbc,b.. for steels complying with BS4360

Grade 43 steel with a yield Grade 50 steel with a yield Grade 55 steel with a yieldstress in N/mm2 of: stress in N/mm2 of: stress in N/mm2 of:

215 230 245 280 325 340 355 400 415 430 450N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2370 99 104 109 121 135 139 143 154 148 161 165380 100 106 111 123 137 141 145 157 161 164 169390 101 107 112 125 139 143 148 160 163 167 172400 102 108 114 126 141 145 150 162 166 170 175420 105 111 116 129 145 149 154 167 171 176 181

440 107 113 119 132 148 153 158 172 176 181 186460 109 115 121 135 151 157 162 176 181 185 191480 111 117 123 137 154 160 165 180 185 190 196500 112 119 125 140 157 163 168 184 189 194 200520 114 121 127 142 160 166 171 188 193 198 204

540 115 122 129 144 163 169 174 191 196 202 208560 117 124 131 146 165 171 177 194 200 205 212580 118 125 132 148 167 174 180 197 203 208 216600 120 127 134 150 170 176 182 200 206 212 219620 121 128 135 152 172 178 184 203 209 215 222

640 122 129 137 153 174 180 187 205 211 217 225660 123 131 138 155 176 182 189 208 214 220 228680 124 132 139 156 177 184 191 210 217 223 231700 125 133 141 158 179 186 193 213 219 225 234720 126 134 142 159 181 188 195 215 221 228 236

740 127 135 143 161 182 189 196 217 223 230 238760 128 136 144 162 184 191 198 219 226 232 241780 129 137 145 163 185 193 200 221 228 234 243800 130 138 146 164 187 194 201 223 229 236 245850 132 140 148 167 190 198 205 227 234 241 250

900 134 142 150 169 193 201 209 231 238 245 255950 135 144 152 172 196 204 212 235 242 249 2591000 137 145 154 174 199 207 215 238 246 253 2631050 138 147 156 176 201 209 217 241 249 257 2671100 140 148 157 178 203 211 220 244 252 260 270

1150 141 150 159 179 205 214 222 247 255 263 2731200 142 151 160 181 207 216 224 249 258 266 2761300 144 153 163 184 211 220 228 254 262 271 2821400 146 155 165 187 214 223 232 258 267 275 2871500 148 157 167 189 217 226 235 262 271 279 291

1600 149 159 169 191 219 229 238 265 274 283 2951700 151 160 170 193 222 231 241 268 277 286 2981800 152 162 172 195 224 233 243 271 280 290 3021900 153 163 173 196 226 236 245 274 283 292 3052000 I 154 164 174 198 228 237 247 276 286 295 308

iiii!!!!!iiiiiiii-iiii!!!!!

*(fJ

*


17

Table 14. Basic average shear stress Pq,bas in stiffened webs of steel complying with BS 4360(see also 6.1.5.2 and table 7)

(a) Grade 43 steel complying with BS 4360

dlt Pq,bas for different distances between stiffeners

O.2d O.3d O.4d O.5d O.6d O.7d O.8d O.9d 1.0d 1.1d 1.2d 1.3d 1.4d 1.5d

N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2

70 91 91 91 91 91 91 91 91 91 91 91 91 91 9175 91 91 91 91 91 91 91 91 91 91 91 91 91 9180 91 91 91 91 91 91 91 91 91 91 91 91 91 9185 91 91 91 91 91 91 91 91 91 91 91 91 91 91

90 91 91 91 91 91 91 91 91 91 91 91 91 91 9195 91 91 91 91 91 91 91 91 91 91 91 91 91 90

100 91 91 91 91 91 91 91 91 91 91 91 90 89 89105 91 91 91 91 91 91 91 91 91 91 90 89 88 87

110 91 91 91 91 91 91 91 91 91 90 89 87 86 86115 91 91 91 91 91 91 91 91 90 89 87 76 85 84120 91 91 91 91 91 91 91 90 89 87 86 85 83 83125 91 91 91 91 91 91 91 89 88 86 85 83 82 81

130 91 91 91 91 91 91 90 88 87 85 83 82 81 80135 91 91 91 91 91 91 89 87 86 84 82 80 79 78140 91 91 91 91 91 90 87 86 84 82 80 79 78 77150 91 91 91 91 91 88 85 83 82 80 78 76 75 74

160 91 91 91 91 89 86 83 81 79 77 75 73 72 71170 91 91 91 91 87 84 81 79 77 75 72 71 69 68180 91 91 91 89 85 81 79 76 75 72 70 68 66 65190 91 91 91 88 83 79 76 74

200 91 91 91 86 81 77 74 72 The stepped line applies to steels of210 91 91 90 84 79 75 72 Ys= 280 N/mm2 and 245 N/mm2 for which220 91 91 89 83 78 73 70 the maximum value of Pq,besis 91 N/mm2230 91 91 87 81 76 71

For steels of Ys= 230 N/mm2 the maximum240 91 91 86 79 74 69 value of Pq,baS is 85 N/mm2250 91 91 85 78 72 67260 91 91 83 76 70 For steels of Ys= 215 N/mm2 the maximum270 91 90 82 75 68 value of Pq,baS is 77 N/mm2


6.2 Lattice girders and trusses: verification relative tothe yield stress

6.2.1 Designprocedure.For lattice members, designverification relative to the yield stress shall be carried outin accordance with 6.2.2 to 6.2.4:

(a) for the lattice as a whole;

(b) for the individual members comprising the lattice.

NOTE. Secondary stresses in lattice girders and trusses. Relaxationsin some requirements of 6.2.2 to 6.2.4 are allowed in cases wheresecondary stresses are calculated and taken into account in thedesign (see 6.3).

6.2.2 The lattice as a whole

6.2.2.1 Subjected to axial tension. The lattice shall bedesigned as an axially loaded tie. The basic stress shall notexceed the value of Pat,beS given in 6.1.2.

6.2.2.2 Subjected to axial compression. The lattice shallbe designed as an axially loaded strut using the maximum

effective slenderness ratio s as defined in 6.1.3 for thelattice as a whole. The basic stress shall not exceed thevalue of Pac,besgiven in 6.1.3.

6.2.2.3 Subjected to bending

6.2.2.3.1 Latticebox girders.For lattice box girders havingan l/r y not exceeding 140 and a depth-to-breadth ratio notexceeding 6, the basic stress Pat,bas and P8/C,basshall notexceed the value of Pat,bel as given in 6.1.2 (where 1and ryare as defined in 6.1.3). Lattice box girders having a depth-to-breadth ratio exceeding 6 shall be designed as latticetrusses. The girder shall be stiffened to prevent distortionof the cross-sectional shape when the girder deflects.

6.2.2.3.2 Lattice trusses. For lattice trusses, and lattice boxgirders having a depth-to-breadth ratio exceeding 6, the maincompression members shall be designed as axially loadedstruts using the basic compressive stresses P8/Cbas givenin 6.1.3 and the effective lengths specified in 'S.1. The maintension members shall be designed as axially loaded ties.

18

Table 14 (continued)(b) Grade 50 steel complying with BS 4360

d/t Pq,b.. for different distanceo bet_n atiffener.

O.2d O.3d O.4d O.5d O.6d O.7d O.ad O.9d 1.0d Ud 1.2d 1.3d 1.4d 1.5d

N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm270 131 131 131 131 131 131 131 131 131 131 131 131 131 13175 131 131 131 131 131 131 131 131 131 131 131 131 131 13080 131 131 131 131 131 131 131 131 131 131 131 130 129 12785 131 131 131 131 131 131 131 131 131 131 129 127 126 125

90 131 131 131 131 131 131 131 131 131 129 127 125 123 12295 131 131 131 131 131 131 131 130 129 126 124 122 121 119

100 131 131 131 131 131 131 131 128 127 124 122 120 118 117105 131 131 131 131 131 131 129 126 124 122 119 117 116 114

110 131 131 131 131 131 130 127 124 122 119 117 115 113 111115 131 131 131 131 131 128 125 122 120 117 114 112 110 109120 131 131 131 131 130 126 123 120 118 115 112 110 108 106125 131 131 131 131 129 124 121 118 116 112 110 107 105 103

130 131 131 131 131 127 122 119 116 114 110 107 105 102 101135 131 131 131 131 125 121 117 114 111 108 105 102 100 98140 131 131 131 130 124 119 115 112 109 105 102 100 97 95150 131 131 131 127 120 115 111 107 105 101 97 94 92 90

160 131 131 131 124 117 111 107 103 100 96 93 89 87 85170 131 131 129 121 114 108 103 99 96 92 88 84 82 79180 131 131 127 118 110 104 99 95 92 87 83 79 76 74190 131 131 124 115 107 100 95 91

200 131 131 122 112 104 97 91 86 The stepped line applies to steels of210 131 131 119 109 100 93 87 Y. =355 N/mm2 for which the maximum220 131 129 117 106 97 89 83 value of Pq,b8. is 131 N/mm2230 131 127 115 103 94 86

For steels of Y. =340 N/mm2 the maximum240 131 125 112 100 90 82 value of Pq,b8. is 126 N/mm2250 131 123 110 98 87 78260 131 121 107 95 84 For steels of Y. =325 N/mm2 the maximum270 121 120 105 92 80 value of Pq,b8Iis 120 N/mm2


*(I)

. *

The basic stresses shall not exceed the value of Pet bu givenin 6.1.2. '

6.2.2.4 Subjected to axial tension and bending, and axialcompression and bending. The lattice shall be so propor-

tioned that in the tension chord members

fet fbt-+-:s;;;Pet Pbt

where

fat, Pat, fbt, Pbt are as defined in 6.1.7.1.2.

In the compression chord members

fac fbe-+1.1-:S;;;1Pac Pbe

where

fae

Pac

is the calculated axial compressive stress;

is the permissible axial compressive stresscorresponding to the maximum effectiveslenderness ratio of the lattice as a whole;

fbe is the calculated maximum compressive stress dueto bending about the principal axes of the latticeas a whole;

Pbe is the permissible compressive stress in bendingbased upon the value of the basic stress given intable 7 for parts in bending (tension or compression).

6.2.3 Individual members of a lattice

6.2.3.1 The basic stresses in the individual members of alattice shall not exceed those given in 6.1.

6.2.3.2 In the case of an individual member subjected toaxial compression due to loadings applied to the lattice asa whole at panel points, the total compressive stress in themember shall not exceed the permissible stress correspond-ing to the effective slenderness of the member betweenpanel points as given in 8.1.

6.2.3.3 In the case of an individual member subjected to acombination of bending stresses due to loads applied to themember between panel points and axial stresses due to

19

Table 14 (concluded)

(c) Grade 55 steel complying with BS 4360

d/t Pq,bas for different distenclS between stiffeners

O.2d O.3d O.4d O.5d O.6d O.7d O.ad O.9d 1.0d 1.1d 1.2d 1.3d 1.4d 1.5d

N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm2 N/mm270 167 167 167 167 167 167 167 167 167 167 167 167 167 16775 167 167 167 167 167 167 167 167 167 167 167 167 167 16680 167 167 167 167 167 167 167 167 167 167 167 166 164 16285 167 167 167 167 167 167 167 167 167 167 164 162 161 159

90 167 167 167 167 167 167 167 167 167 164 161 159 157 15695 167 167 167 167 167 167 167 166 164 161 158 156 154 152

100 167 167 167 167 167 167 166 164 161 158 155 153 151 149105 167 167 167 167 167 167 164 161 159 155 152 149 147 145

110 167 167 167 167 167 165 161 158 156 152 149 146 144 142115 167 167 167 167 167 163 159 156 153 149 146 143 141 139120 167 167 167 167 166 161 156 153 150 146 143 140 137 135125 167 167 167 167 164 158 154 150 148 143 140 137 134 132

130 167 167 167 167 162 156 151 148 145 140 137 133 131 128135 167 167 167 167 160 154 149 145 142 137 133 130 127 125140 167 167 167 165 158 151 146 142 139 134 130 127 124 121150 167 167 167 161 153 147 141 137 134 128 124 120 117 115

160 167 167 167 158 149 142 136 132 128 123 118 114 111 108170 167 167 165 154 145 137 131 126 122 117 112 108 104 101180 167 167 161 150 141 133 126 121 117 111 106 101 97 94190 167 167 158 147 136 128 121 115

200 167 167 155 143 132 123 116 110 The stepped line applies to steels of210 167 167 152 139 128 119 111 Y. = 450 N/mm2 for which the maximum220 167 164 149 135 124 114 106 value of Pq,ba.is 167 N/mm2230 167 162 146 132 119 109

For steels of Y. = 430 N/mm2 the maximum240 167 160 143 128 115 104 value of Pq,ba. is 159 N/mm2250 167 157 140 124 111 100260 167 155 137 121 107 For steels of Y. = 415 N/mm2 the maximum270 167 152 134 117 102 value of Pq,ba' is 154 N/mm2

For steels of Y. = 400 N/mm2 the maximumvalue of Pq,_ is 148 N/mm2

as 4465 : 1989

Section two

loadings on the lattice as a whole at panel points. the com-bined stress formulae given in 6.1.7.1.2 and 6.1.7.1.3 shallbe used.

6.3 Secondary stresses

Secondary stresses shall be added to the coexistent(primary) stresses in the individual members and shall be

checked in accordance with the following.

NOTE. For the purposes of this standard, stresses in the individualmembers of lattice or braced structures that are the result ofeccentricitY of connections, elastic deformation of the structure,and rigiditY of joints are defined as secondary stresses. Wheresecondary stresses are computed and added to the coexistent(primary) stresses calculated in accordance with 6.1 and 6.2 higherstress levels are permitted.

(a) Members subjected to axial compression and bending

fac fbc-+-=s;;;; 1.20Pac Pbe

subject to the limitation that

fac-=s;;;; 1.0Pac

where

fac. Pac. fbe and Pbc are as defined in 6.1.7.1.2.(b) Members subjected to axial tension and bending

fat fbt-+ -=s;;;; 1.20Pat Pbt

subject to the limitation that

fat-=s;;;; 1.0Pat

where

fat. Pat. fbt and Pbt are as defined in 6.1.7.1.3.

20

7 Basic stresses in connections

7.1 Welds

7.1.1 General. All welding on loadbearing structures shallbe carried out in accordance with BS 5135.

7.1.2 General butt welds

7.1.2.1 All butt welds shall be made using a type ofelectrode (or other welding consumable) that will produceall-weld tensile test specimens as specified in BS 709 havingboth a yield strength and a tensile strength not less thanthat of the parent metal.

Where electrodes complying with BS 639 are used to weldsteel complying with BS 4360 the matching electrodes forbutt welds are as follows.

Steel grade in BS 4360 Classification of electrodescomplying with BS639

4350WR 5055

E43 RE51 BE51 B*E51 B

iiiiii!!!!!iiiiiiiiiiii

Electrodes for use with grade 55 steel shall have a minimumall-weld yield stress of 450 N/mm2 and a minimum tensilestrength of 550 N/mm2 .7.1.2.2 The basic strength of a butt weld shall be taken asequal to that of the parent metal, provided that the weldcomplies with 7.1.2.1.

7.1.2.3 Interm ittent complete-penetration butt welds shallbe used only to resist shear. The effective length of anintermittent weld shall be taken as its overall length minus2t', where t' is the thickness (in mm) of the thinner partjoined. The minimum effective length of any such weld shallbe not less than 4t' or less than 40 mm, and the longitudinalspace between the effective lengths of weld shall be notmore than 12t'.NOTE. Where fatigue is a design criterion, intermittent butt weldsare not to be used.

iiiiii!!!!!

*U)

*

7.1.3 Butt welds with partial penetration

7.1.3.1 A continuous partial-penetration butt weld weldedfrom one side only or from both sides can be used providedthat it is not subjected to a bending moment about thelongitudinal axis of the weld other than that resulting fromthe eccentricity of the weld metal relative to the partsjoined or from secondary moments.

A partial-penetration butt weld welded from one side onlyshall not be subjected to any loading that would cause theroot of the weld to be in tension if failure due to suchtension would be liable to be progressive and lead to struc-tural collapse unless it can be demonstrated that properattention has been paid to the detailed design of the joint,and testing and operational experience have shown thisdetail to be satisfactory.

7.1.3.2 The throat thickness of a partial-penetration buttweld welded from one side only shall be taken as the depthof penetration and the adverse effect of the eccentricity of

*Special electrodes may be necessary to suit weather-resisting steel.


the weld metal relative to the parts joined shall also beallowed for when calculating the strength.The specified penetration of such a weld shall be not lessthan 2 v't' where t' is the thickness (in mm) of the thinnerpart joined.

7.1.3.3 The throat thickness of a partial-penetration buttweld welded from both sides shall not be taken as morethan the total depth of penetration relative to the surfacesof the thinner part joined. Except where it can be shownthat greater penetration can consistently be achieved,the depth of penetration from each side shall not be takenas more than the depth of grooved weld preparation on thatside in the case of a J or U weld, or more than the depth ofgroove less 3 mm in the case of a V or bevel weld.Where the weld metal is placed asymmetrically relative tothe axis of the parts joined, the adverse effect of theeccentricity shall also be allowed for when calculating thestrength of the weld.The specified penetration from each side of such a weldshall be not lessthan 2v't' where t' is the thickness (in mm)of the thinner part joined.

7.1.3.4 The basic strength of a compound weld comprisinga partial-penetration butt weld reinforced by a fillet weldshall be calculated as for a deep-penetration fillet weld(see 7.1.4.3).

7.1.4 Fillet welds

7.1.4.1 The effective throat thickness aw of a fillet weld(other than a deep-penetration fillet weld covered by 7.1 A.3)shall be taken as the maximum perpendicular distance fromthe root of the weld to a straight line joining the fusionfaces that lies within the cross section of the weld (as shownin figure 3). However aw shall not be taken as more than0.7Sw, where Sw is the effective leg length of the weld asdefined by the figure (or the average if the legs are unequal).

7.1.4.2 Fillet welds shall not be considered capable oftransmitting primary loadings between connecting parts thefusion faces of which form an angle of more than 1200 orless than 600, except in the case of hollow sections contin-uously welded around the periphery, where the normallimitations are 150 0 and 30 0, which can be exceededsubject to proof of efficiency (see appendix D of BS 5135 :1974).

7.1.4.3 Deep-penetration fillet welds shall be used onlywhere it can be shown that the required penetration canconsistently be achieved, for example by automatic weldingprocesses. The depth of penetration dw shall be measuredas shown in figure 4 and shall be at least 2 mm. The effec-tive leg length Sw and the design throat thickness aw shallbe taken as shown in the figure.

7.1.4.4 The maximum stress in a fillet weld shall be takenas the vector sum of the stresses due to all forces andmoments transmitted by the weld, each based on a thick-ness equal to the design throat thickness aw.

The basic stress Pw,ba8 in a fillet weld, based on a thicknessequal to the design throat thickness aw, shall not exceed0.3Us., where Us. is the tensile strength of the electrode or

21

Table 15. Basic stresses in welds

Steel grade Electrodes complying with BS 639in BS4360

Clallification Clallification ClallificationE43 R E51 B E51 B

Use = Use = Use ..430 N/mm2 510 N/mm2 550 N/mm2

N/mm2 N/mm2 N/mm2

43 118 126 12650 118 144 144WR 50 118 141* 141*55 118 147 162t

*147 N/mm2 for structural hollow sections of grade WR 50.

tThis applies only when electrodes with a minimum yieldstress of 450 N/mm2 and a minimum tensile strength of550 N/mm2 are used.


other welding consumable based on all-weld tensile tests asspecified in as 709. However Pw,b8S shall not be taken asmore than 0.3Us, where Us is the minimum ultimate tensilestrength of the parent metal.

Where electrodes complying with as 639 are used to weldsteel complying with as 4360, the basic weld stresses Pw besgiven in table 15 shall apply. '

7.1.4.5 The effective length of a discontinuous run offillet weld shall be taken as the overall length less 2Sw'The effective length of a fillet weld required to transmitprimary loading shall be not less than 40 mm or less than

4Sw'

7.1.4.6 The space along anyone edge of an elementbetween consecutive effective lengths of intermittent filletwelds (other than those interconnecting the components ofback-to-back tension or compression members) shall notexceed 300 mm nor shall it exceed 16t' for elements incompression or 24t' for elements in tension, where t' is thethickness of the thinner part joined.

An intermittent fillet weld connecting components subjectto primary loadings shall extend to the end of the partconnected.

7.1.4.7 Where the end of an element is connected only byintermittent fillet welds the transverse spacing of the weldsshall not exceed 200 mm and the length of each weld shallbe not less than the transverse spacing.

7.1.4.8 A single fillet weld shall not be subjected to abending moment about its longitudinal axis that is producedby primary loading.

A single fillet weld shall not be subjected to any loadingthat would cause the root of the weld to be in tension iffailure due to such tension would be liable to be progressiveand to lead to structural collapse unless it can be demon-strated that proper attention has been paid to the detaileddesign of the joint and testing and operational experiencehas shown this detail to be satisfactory.

7.2 Basic stresses for bolts, studs and rivets

7.2.1 Bolts and studs

7.2.1.1 Friction grip bolts. These bolts shall comply withas 4395 : Parts 1, 2 and 3 and shall be fitted in accordancewith as 4604 : Parts 1, 2 and 3.

In the design of joints using friction grip bolts, the dutyfactor (see 5.3) shall be taken as 1.0 irrespective of thehoist classification.

7.2.1.2 Precision bolts

7.2 1.2.1 General. Precision bolts shall be turned or coldfinished and fitted into reamed or drilled holes whosediameter shall not exceed the diameter of the bolts bymore than 0.4 mm.

7.2.1.2.2 Bolts in tension

7.2.1.2.2.1 Bolts not tightened by controlled means.The basic permissible tensile stress Pet,bas at the root of thethread for these bolts shall not exceed

Pat,bl!lS = 0.4YRO.2

where

YR0.2 is the yield stress or 0.2 % proof stress of thematerial.

Where there is a fluctuating load or a reversal of load acrossthe joint, the number of bolts or studs required shall bedetermined in accordance with 9.7 except in the case ofbolts or studs having a yield stress in excess of 250 N/mm2 .In such cases, the difference between the stresses corres-ponding to fmax and fm1n shall be not greater than 10 % ofthe ultimate tensile strength of the material and the meanstress shall be not greater than 15 % of the ultimate strengthof the material.

7.2.1.2.2.2 Bolts tightened by controlled means. Thesebolts shall be tightened by controlled means so that thepretensioned stress Pat at the root of the thread is notgreater than 0.8YRO.2 or less than 0.7YRO.2.

The virtual permissible stress Pat,virt at the root of thethread induced in these bolts by external loading shall notexceed:

Pet,virt = 0.48 YR 0.2 for non-fluctuating loads;

Pat,virt = 0.40YRO.2 for fluctuating loads.

7.2.1.2.3 Bolts in shear. The basic shear stress Pq,bas forthe section of the bolt at the interface of the joint shall notexceed

Pq,bl!lS = 0.375YRO.2Where there is a fluctuating load or a reversal of load acrossthe joint, the number of bolts or studs required shall bedetermined in accordance with clause 9.

7.2.1.2.4 Bolts subjected to combined tension and shear.A check shall be made that

fat =r;;;;Pat

fq =r;;;;Pq

...; (fal + 3fq 2) :s;;;1.2Pet

22


iiii!!!!!iiiiiiii Figure 3. Design throat thickness of fillet weldsiiii!!!!!

- *(f)

*

Figure 4. Design throat thickness of deep-penetrationfillet welds

23

Table 16. Basic stresses in rivets as a percentageof YRO.2

Type In tension Inshear In bearing

% % %

Power-driven shop rivets 40 43.5 90*

Power-driven field rivets 40 40 85*

Hand-driven rivets 40 36.5 80*

*The YRO.2of the rivet or the joint material, whichever is thelower, should be used to determine the basic bearing stress.

Table 17. Effective lengths of parts in compression

Diagrammatic Restraint conditions Effectiverepresentation length 1

Effectively held in o.n, . position and

1\restrained in direc-tion at both ends

\ LII

'/ '/ '/

, Effectively held in 0.85Lposition at both

I]ends and restrainedin direction at oneend

,Effectively held in 1.0Lposition at both

[]ends but notrestrained indirection

,Effectively held in 1.5Lposition and

IJrestrained in direc-tion at one end andpartially restrainedin direction but notheld in position atthe other

Effectively held in 2.0L, position and

Drestrained in direc-tion at one end butnot held in positionor restrained indirection at theother end


7.2.1.2.5 Bolts in bearing. The basic permissible pressurePb,bas in the hole shall not exceed the value

Pb,bas = 0.9 YR 0.2

where

Y R0.2 is the yield stress or 0.2 % proof stress for thebolt or for the joint material, whichever gives thelowest value.

7.2.1.3 Black bolts other than friction grip bolts. Blackbolts shall not be used in main members, in shear for jointsin stress-bearing members, or in joints subjected to fatigue.

For other applications of use the basic permissible stressesshall not exceed:

P fIt,bas = 0.4 Y R0.2 tensionPq,bas = 0.33YRO.2 shear

where

Y R0.2 is as defined in 7.2.1.2.2.1;

Pm. bas = 0.66YRO.2 bearing

where

Y RO.2 is as defined in 7.2.1.2.5.

7.2.2 Rivets. The basic stresses for rivets shall be as givenin table 16. Where there is a fluctuating load or a reversal ofload across the joint, the number of rivets shall be deter-mined in accordance with clause 9.

8 Proportions of structural components,plates and web stiffeners

8.1 Effective lengths of parts in compression

8.1.1 Struts. For the purpose of calculating slendernessratio 1/r for struts, the effective length (1) given in table 17shall be taken, where L is the actual length of the memberas shown in the appropriate figure of table 17.

8.1.2 Single web plate girders and rolled beams

8.1.2.1 The effective length (1) of the compression flangefor buckling normal to the plane of the girder to be used asdescribed in 6.1.4.2.3 shall be as given in 8.1.2.2 and 8.1.2.3.

8.1.2.2 Where there are no lateral bracings between com-pression flanges and no cross frames the effective lengthshall be as shown in table 17.

Restraint against torsion shall be provided by web or flangecleats, bearing stiffeners, lateral end frames or other sup-ports to the end of the compression flanges.

24

8.1.2.3 Where there is effective lateral bracing direct tocompression flanges the effective length shall be as shownin figure 5.

Plan view

L1=tOL

Figure 5. Effective length with lateral bracing

8.1.3 Lattice structures

8.1.3.1 Effective length of a lattice structure as a whole.Where there is no adequate lateral bracing, the effectivelength shall be taken as the span when considering bucklingnormal to the plane of the member.

8.1.3.2 Effective lengths of the individual members of alattice structure

8.1.3.2.1 Main mast or tower members. For main mast ortower members the effective length shall be 0.85 times thedistance between centres of intersection of bracing membersin the plane in which buckling is being considered.

Where there is no adequate lateral bracing, the effectivelength when considering buckling normal to the plane ofthe structure shall be taken as the span, as in 8.1.3.1.

8.1.3.2.2 Bracing (or web) members axially loaded.For bracing or web members aXially loaded the effectivelength shall be:

(a) 0.70 times the distance between centres of inter-

section with the main members for buckling in the planeof the mast or tower; and(b) 0.85 times the distance between centres of inter-

section with the main members for buckling normalto the plane of the mast or tower.

In the case of cross-braced systems the effective length of amember shall be taken as 0.85 times the greatest distancebetween any two intersections when considering bucklingin the plane of the mast or tower.

8.1.3.2.3 Single-angle discontinuous struts connected togussets or to a section. For single-angle discontinuous strutsconnected to gussets or to a section, either by riveting or bybolting with not less than two bolts in line along the angle at

*(J)

*


each end, or by their equivalent in welding, the eccentricityof the connection with respect to the centroid of the strutcan be ignored and the strut designed as an axially-loadedmember. This is provided that the calculated average stressdoes not exceed the allowable stresses derived from thebasic stresses given in 6.1.3 in which 1 is the length of thestrut, between the centres of the fastenings at each end,and r is the minimum radius of gyration.

8.1.3.2.4 Single-angle discontinuous struts intersected by,and effectively connected to, another angle in cross bracing.For single-angle discontinuous struts intersected by,and effectively connected to, another angle in cross bracing,the effective length in the plane of the bracing shall be takenas in 8.1.3.2.2. In the plane normal to the plane of thebracing, the effective length 1 shall be taken as the distancebetween the points of intersection and the centroids ofthe main members. In calculating the slenderness ratio,the radius of gyration about the appropriate rectllngularaxis shall be taken for buckling normal to the plane of thebracing and the least radius of gyration for buckling in theplane of the bracing.

8.1.4 Cantilever beams without intermediate lateral support

8.1.4.1 The effective length (1) of cantilever beams ofprojecting length L to be used in 6.1.3.2 shall be as follows.

(a) Built-in at the support

(1) Free at the end 1=0.85L(2) Restrained against torsion at the free

end by contiguous construction 1=0.75L(3) Restrained against lateral deflection

and torsion at the free end 1=0.50 L(b) Continuous at the support

(1) Unrestrained against torsion atthe support and free at the end 1=3L(2) With partial restraint against torsion

at the support and free at the end 1=2 L(3) Restrained against torsion at thesupport and free at the end 1= L

8.1.4.2 For cases (1), (2) and (3) of8.1.4.1(b) in which thecantilever end is not free but is subject to a degree ofrestraint, the effective length shall be multiplied by a factoras follows.

(a) Where the end is restrained against torsion by

contiguous construction, the effective lengths givenin 8.1.4.1(b) shall be mUltiplied by a factor of 0.88.(b) Where the end is restrained against lateral deflection

and torsion, the effective lengths given in 8.1.4.1 (b) shallbe multiplied by a factor of 0.59.

8.1.4.3 For cantilever beams loaded on the compressionflange, the effective lengths given in 8.1.4.1 (a) and (b)and 8.1.4.2 shall be increased by a factor of 1.2.

25


Table 18. Effective length with no lateral bracing

Load appl ied to the tension flenga Restraint conditions againstleteral bending and torsionof section

Ends completely restrained

1=0.7L

Ends partially restrained

E..#======~1= 0.85L

Ends unrestrained

1= -~--------

1= 1.0L

8.2 Widths of plates

8.2.1 Effective widths of plates in compression. For thecomputation of the effective cross-sectional area of acompression member subjected to the design checks givenin 6.1.3, the effective width of an unstiffened plate, in termsof its width b measured between adjacent lines of rivets,bolts or welds connecting it to other parts of the section,shall be as follows.

(a) For riveted, bolted or stress relieved welded members

(1) Using grade 43 steel complying with BS 4360

for bIt' ~ 45, the effective width = bfor bIt' > 45, the effective width = 45t'


for blt'.so;; 40, the effective width = bfor bIt' > 40, the effective width = 40t'

Load applied to the compr_ion flange andboth load end flange fr88 to move laterally

1=0.85L

R=== = = =E31= 1.0 L

1= 1.2 L


for bIt' ~ 35, the effective width =bfor bIt' > 35, the effective width =35t'

(b) For as-welded members(1) Usinggrade 43 steel complying with BS 4360

for bIt' ~ 30, the effective width = bfor bIt' > 30, the effective width= 40t'(blt' - 18)/(blt' - 14)

(2) Usinggrade 50 steel complying with BS 4360

for bIt' '" 27, the effective width = bfor bIt' > 27, the effective width= 34t'(blt' - 15)/(blt' - 12)

(3) Usinggrade 55 steel complying with BS 4360

for bIt' OS;;;23, the effective width = bfor bIt' > 23, the effective width= 30t'(blt' - 13)/(blt' - 10)

26

Table 19. Maximum width of plates in compression

Grad. of steel Riv.ted, bolted or A._Idee!to BS 4360 str....r.lI.ved w.lded members

members

43 90t' 80t'50 80t' 70t'55 70t' 60t'

Table 20. Projection of unstiffened compressionflange plates

Grad. of st.eI Riveted, bolted or As.weldedto BS 4360 str....r.lleved w.lded members

m.mbers

43 16t' 12t'50 14t' 12t'55 12.5t' 12t'

In (a) and (b). t' is the thickness of the thinnest plate, orthe aggregate thickness of two or more plates providedthese plates are adequately connected together.

8.2.2 Maximum width of plates in compression

8.2.2.1 The width of a plate, measured between adjacentlines of rivets, bolts or welds connecting it to other parts ofthe section, unless effectively stiffened, shall not exceed thevalues given in table 19, where t' is as defined in 8.2.1.

iiii!!!!!!iiiiiiii

8.2.2.2 Compression flange plates unstiffened at theiredges shall not project beyond the outer line of connectionsto the flange angles (or where there are no flange angles tothe tongue plates) by more than the values given in table 20,where t' is as defined in 8.2.1.

-iiii!!!!!!

*(/)

*

8.2.3 Maximum widths of plates in tension. In all cases,tension flange plates, stiffened or unstiffened at their edges,shall not project beyond the line of connections to the webor tongue plates by more than 12t', where t' is as definedin 8.2.1.

8.3 Web plates and web stiffeners

8.3.1 Minimum thickness of web plates for open sections

8.3.1.1 For unstiffened webs. The thickness t of the webplate shall be not less than:

dd85 for grade 43 steel complying with BS 4360;

d1 /75 for grade 50 steel complying with BS 4360;

d1/65 for grade 55 steel complying with BS 4360;

where d1 is the clear distance between flange angles or,where there are no flange angles, between flanges (ignoringfillets); where tongue plates having a thickness not less thantwice the thickness of the web plate are used, d1 is thedepth of the girder between the flanges less the sum of thedepths of the tongue plates or eight times the sum of thethickness of the tongue plates, whichever is the less.


8.3.1.2 For vertically stiffened webs. The thickness t of theweb plates shall be not less than:

1/180 of the small clear panel dimension;1/270 of the greater clear panel dimension and d2/200for grade43 steel complyingwith BS4360 or d2/180for grade50 steel complying with BS4360 or d2/155for grade 55 steel complying with BS4360;

where

d2 is twice the clear distance from the compressionflange angles or plate or tongue plate to the neutralaxis.

8.3.1.3 For webs stiffened both vertically and horizontallyand with the horizontal stiffener at a distance from thecompression flange of 2/5 of the distance from the com.pression flange to the neutral axis. The thickness t of theweb plate shall be not less than:

1/180 of the smaller clear dimension in each panel;

1/270 of the greater clear panel dimension and d2/250for grade 43 steel complying with BS 4360 or d2/225for grade 50 steel complying with BS 4360 or d2/190for grade 55 steel complying with BS 4360.

When there is also a horizontal stiffener at the neutral axisof the girder, the thickness t of the web plate shall be notless than:

1/180 of the smaller clear dimension in each panel;

1/270 of the greater clean panel dimension and d2/400for grade 43 steel complying with BS 4360 or d2/360for grade 50 steel complying with BS 4360 or d2/310for grade 55 steel complying with BS 4360;

where

d2 is as defined in 8.3.1.2.

8.3.2 Web stiffeners for open sections

8.3.2.1 Loadbearing web stiffeners

8.3.2.1.1 Rolled I beams and channels. For rolled I beamsand channels, loadbearing stiffeners shall be provided atpoints of concentrated load (including points of support)where the concentrated load or reaction exceeds the value

Pac x t X Lbwhere

Pac is the permissible axial stress for struts as givenin 5.1.3 corresponding to a slenderness ratio of1.7d3/t and ex=5.5;

t is the web thickness;

d3 is the clear depth of web between root fillets;

Lb is the length of the stiff portion of the bearing plusthe additional length given by dispersion at 45 0 tothe level of the neutral axis, and measured along theneutral axis.

The stiff portion of a bearing is the length that cannotdeform appreciably in bending, and shall not be taken asgreater than half the depth of the beam for simply supportedbeams and the full depth of the beam for continuous beams.

27


8.3.2.1.2 Plate girders. For plate girders, loadbearingstiffeners shall be provided at points of support and atpoints of concentrated load where the web would otherwisebe overstressed (see 8.3.2.1.1).

8.3.2.1.3 Details of stiffeners. Loadbearing stiffeners shallbe symmetrical about the web, where possible.

Loadbearing stiffeners in which the concentrated loadcauses compression shall be designed as struts, assuming thatthe section consists of a pair of stiffeners together with alength of web on each side of the centreline of the stiffenersequal to 20 times the web thickness. The radius of gyrationshall be taken about the axis parallel to the web of thebeam or girder and the calculated stress shall not exceed theallowable stress for a strut, assuming an effective lengthequal to 0.7 times the length of the stiffener.

The outstanding legs of each pair of loadbearing stiffenersshall be so proportioned that the bearing stress on that partof their area in contact with the flange and clear of the rootof the flange or flange angles or clear of the flange weldsdoes not exceed the bearing stress specified in 6.1.6.

Loadbearing stiffeners shall be provided with sufficientrivets, bolts or welds to transmit to the web the whole ofthe load in the stiffeners.

Loadbearing stiffeners shall be fitted to provide a tight anduniform bearing upon the flange transmitting the load orreaction unless welds are provided between the flange andstiffener for this purpose. At points of support this require-ment shall apply at both flanges. Where the ends of stiff-eners are not fitted or connected to the flange, they shallbe kept well clear of the flange.

Loadbearing stiffeners shall not be joggled and shall besolidly packed throughout.

When load bearing stiffeners at supports are the sole meansof providing restraint against torsion, the stiffener shall beso proportioned that

D3 TmaxRI~

250Wwhere

I is the moment of inertia of the pair of stiffenersabout the centreline of the web-plate;

D is the overall depth of the girder;

Tmax is the maximum thickness of the compressionflange;

R is the reaction on the bearing;

W is the total load on the girder.

8.3.2.2 Intermediate stiffeners

8.3.2.2.1 Vertical stiffeners. To limit web buckling, verticalintermediate stiffeners shall be provided throughout thelength of the girder at a distance apart not greater than1.5d1 when the thickness of the web is less than d1 /85 forgrade 43 steel complying with BS 4360 or d1 /75 forgrade 50 steel complying with as 4360 or d1/65 forgrade 55 steel complying with BS 4360, where d1 is thedepth of web as defined in 8.3.1.1.

These stiffeners shall be so designed that

d13 X t3I ~ 1.5 25t

where

I is the moment of inertia of a pair of stiffeners aboutthe centre of the web, or of a single stiffener aboutthe face of the web;

t is the minimum required thickness of the web;

5t is the maximum permitted clear distance betweenstiffeners for thickness t.

NOTE. Where, on the basis of requirements of strength, the webthickness provided is greater than the minimum required, or thestiffener spacing is made closer than the maximum permissible,the moment of inertia of the stiffeners nead not be correspondinglyincreased.

Intermediate vertical stiffeners, when not acting as load-bearing stiffeners, can be joggled and can be in pairs placedone on each side of the web or single, and shall extend tothe full depth of the web. Unless they are connected to theflanges, they shall be kept well clear of them.

8.3.2.2.2 Horizontal stiffeners. Where horizontal stiffenersare used in addition to vertical stiffeners they shall be asfollows.

One horizontal stiffener, on one or both sides of the web,shall be placed at a distance from the compression flangeequal to two-fifths of the distance from the compressionflange to the neutral axis when the thickness of the web isless than:

d2/200 for grade 43 steel complying with as 4360;



where

d2 is the depth of the web as defined in 8.3.1.2.

The stiffener shall have a moment of inertia I not less than451 t3 where I and t are as defined in 8.3.2.2.1 and 51 isthe actual distance between the vertical stiffeners.

A second horizontal stiffener, on one or both sides of theweb, shall be placed on the neutral axis of the girder whenthe thickness of the web is less than:



d:z/190 for grade 55 steel complying with as 4360.

This stiffener shall have a moment of inertia I not less thand:zt3 where I and t are as defined in 8.3.2.2.1 and d:z is asdefined in 8.3.1.2.

Horizontal stiffeners shall extend between vertical stiffenersbut need not be continuous over them, or connected tothem.

8.3.2.2.3 External forces on intermediate stiffeners. Whenvertical intermediate stiffeners are subject to bendingmoments and shears due to the eccentricity of vertical loads,or the action of transverse forces, the moment of inertia Iof the stiffeners given by 8.3.2.2.1 shall be increased asfollows.

28

For bending moment on stiffener due to eccentricity ofvertical loading with respect to the vertical axis of the web

1.5MD2increase of 1=

EtFor lateral loading on stiffener

3PD3increase of I =

Et

iiiii!!!!!!!iiiiiiiiii

where

M is the applied bending moment;

P is the lateral force to be taken by the stiffener anddeemed to be applied at the compression flange ofthe girder;

D is the overall depth of girder;

t is the thickness of web;

E is Young's modulus (= 205 000 N/mm2).

8.3.2.2.4 Connection of intermediate stiffeners to web.Intermediate vertical and horizontal stiffeners not subjectedto external loads shall be connected to the web by welds orrivets in order to withstand a shearing force (in kN/mm)run between each component of the stiffener and the web,of not less than t2 ISh, where t equals web thickness(in mm) and h equals the projection (in mm) of the stiffenercomponent from the web.

8.3.2.3 Outstand of all stiffeners. Unless the outer edgeof each stiffener is continuously stiffened, the outstandof all stiffeners from the web shall be not more than thefollowing:

for sections

16t for grade 43 steel complying with BS 4360;14t for grade 50 steel complying with BS 4360;12.5t for grade 55 steel complying with BS 4360;

for flats

12t for all steels

where

t is the thickness of the section or flat.

-iiiii!!!!!!!

*(/)

*

9 Fluctuating loads: permissible fatiguestresses

9.1 Detail design

All details shall be designed to avoid stress concentrationslikely to result in excessive reduction of the fatigue strengthof members or connections. Care shall be taken to avoidsudden changes of shape of a member or part of a member,especially in regions of tensile stress or local secondarybending.

Except where specifically stated to the contrary, thefatigue stresses permissible under this clause for anyparticular detail shall apply to all steels.NOTE. Memberssubjected to fluctuetlons of stress are liable tosuffer from fatigue failure and this may be caused by loads that


are very much lower than those that would be necessary to causefailure under a single application. The Inltletlon of fatigue cracksis due, primarily, to stress concentrations Introduced by theconstructional details. Discontinuities such as bolt or rivet holes,welds and other local or general changes In geometrical form setup such stress concentrations from which fatigue cracks may beinitiated, and these cracks may subsequently propagate throughthe connected or fabricated member.

9.2 Number of stress cyclesFor calculation purposes the number of stress cycles, N,for all members of the structUre shall be 5 x 105.

9.3 Loads and stresses to be considered

9.3.1 Loads. A verification of the adequacy of structuralmembers for fatigue shall be made on the basis of the loadcombinations specified in 4.1.

9.3.2 Stresses. Under the specified loading combinationsthe elements of a structure will be subjected to a variety ofstress cycles in which both the degree of stress fluctuationand the level of maximum stress will vary. The degree ofstress fluctuation shall be expressed as the ratio fmlnlfmaxwhere fm1nis the minimum stress in the element during acycle and fmax is the maximum stress in the element duringthe same cycle. The maximum stress level, whether tensionor compression, corresponds to

fmax'

9.4 Method

The nominal load spectrum factor, Kp, specified in 4.1,according to the state of loading of the hoist, shall beapplied to the rated load to make an allowance for thevarying loads handled by the hoist throughout its life.

Using this factored load, the ratio fmlnlfmax shall bedetermined for the extreme conditions of stress that occurin a single typical operating cycle due to the combinationof loadings specified in 4.1. The maximum stress thusdetermined shall be in accordance with 9.5.

9.5 Permissible fatigue stress

9.6.1 Table 21 gives the permissible tensife and compressivefatigue stresses, Pft and

Pfc' according to the number ofstress cycles, the class of constructional detail given in 9.6and the ratio fmlnlfm8x' The tabulated stresses areapplicable to grades 43,50 and 65 steels complying withBS 4360.The value of fmax shall not exceed the appropriatepermissible tensile or compressive fatigue stress, Pft or

Pfc' from table 21.Where coexistent bending and shear stresses are present,the principal stress at the point under consideration shallnot exceed the appropriate permissible tensile orcompressive fatigue stress, Pft or

Pfc' from table 21.9.5.2 Under no circumstances shall fmax exceed thepermissible working stresses given in 9.3.2 or any lowerstresses which may be required by other clauses in thisstandard.

29


9.6 Classes of constructional detailsThe classes of constructional detail A to G, referred to intable 21, are described below and shown in figures 6 to 9.

(a) Class A

(1) Plain steel in the as-rolled condition with nogas-cut edges.(2) Members fabricated with full-penetrationlongitudinal or transverse butt welds with the weldoverfill dressed flush with the plate surface and theweld proved free from defects by non-destructiveexamination, provided also that the members do nothave exposed gas-cut edges.

Welds shall be dressed flush by machining or grinding,or both, which shall be finished in the directionparallel to the direction of the applied stress.

(b) Class 8

(1) Members fabricated with continuous longitudinal

butt welds with full or partial penetration made witheither a submerged or open arc automatic process butwith no intermediate stop-start positions within theweld length.

(c) Class C

(1) Members fabricated with continuous longitudinalfillet welds made with either a submerged or open arcautomatic process but with no intermediate stop-startpositions within the weld length.(2) Members fabricated with transverse non-Ioad-carrying fillet or butt welded attachments with theweld fully machined.(3) Members of grade 50 or 55 steel complying withBS 4360 fabricated or connected with rivets or bolts.

(d) Class D

(1) Members fabricated with full-penetrationtransverse butt welds made in the shop in the flatposition, manual welds not giving deep penetrationand automatic welds made by a process other thansubmerged arc welding.(2) Members fabricated with continuous longitudinalfillet welds with stop-start positions within the weldlength.(3) Members fabricated with transverse non-load-carrying fillet or butt welded attachments with theweld toe lightly ground.(4) Members fabricated with longitudinal non-load-carrying fillet or butt welded attachments with theweld ends fully machined.(5) Members of grade 43 steel complying with

BS 4360 fabricated or connected with rivets or bolts.(e) Class E

(1) Members fabricated with longitudinal non-load-carrying fillet or butt welded attachments with theweld ends lightly ground.(2) Girder webs with stiffeners in regions ofcombined bending and shear.(3) Members with stud shear connectors.

(f) Class F

(1) Members fabricated with transverse butt weldsmade on permanent backing material.(2) Members fabricated with transverse butt weldsmade by submerged arc welding or manually bydeep-penetration methods.(3) Members fabricated with transverse non-load-carrying fillet or butt-welded attachments.(4) Members fabricated with transverse butt welds inwhich the load is resisted by bending in the plate.(5) Members fabricated with longitudinal non-Ioad-carrying fillet or butt welded attachments.(6) Members fabricated with intermittent longitudinalfillet welds.(7) Members fabricated with full-penetration

cruciform butt welds.(8) Members fabricated with transverse load-carryingfillet welds.(9) The main chord members of a lattice girder ortruss at the point where a bracing member isconnected to it by a butt or fillet weld.

(g) Class G(1) Members with intermittent longitudinal non-load-carrying attachments butt or fillet welded to theiredges.(2) Members connected by longitudinal load-carrying

fillet welds.(3) Members with partial-length welded cover plates.

(4) The bracing member of a lattice girder or truss atthe point where it is connected to a main member bya butt or fillet weld.(5) Members connected by load-carrying cruciformfillet welds.

9.7 Connections: riveted or bolted

9.7.1 Connections made with rivets and bolts. Noallowance for fatigue shall be made in calculating therequired number of rivets or bolts in a riveted or boltedconnection, except that all rivets or bolts subjected toreversal of stress shall be proportioned for the arithmeticalsum of the load in the member corresponding to 'max plus50 % of the load of opposite sign corresponding to 'min'9.7.2 Connections made with friction grip bolts. Noallowance for fatigue shall be made in calculating therequired number of bolts.

9.8 Connection: load-carrying fillet weldsLoad-carrying fillet welds shall be designed such that thestress on their total effective throat area does not exceedthe relevant value given for class G in table 21.

9.9 Guides and guide rails

9.9.1 Cage guides, guide rails and their fixings shallwithstand all stresses produced by the normal operation ofthe hoist under the worst loading conditions given in 10.1.2and 10.1.3.

30

...

c:J EJ E NO 00(7) 00...(7) (7)NLn O~N ~LnM....... MN N.....M "'000 ..........CO co Ln VVCJ Z VM N...... ... ...

...I&. EJ E N .....(7)00 .....00..... "'0000 OM..... ........N.......

M OOOON OOLnM NO(7) (7)00..... .....COCOCJ Z V MNN ... ... ... ... ...

...w EI E NN..... v...... OOOCO LnLn..... OVO....... MN... Ln...OO LnvN "'0(7) (7)0000u Z vvM NN... ... ... ... ... ... cu

~... ...'in

i0 E

II>I E NN N(7)N LnMCO ...~O "'MCO~1;; ....... M(7)

"'LnN (7).....Ln V N "'0(7) Cco . u Z VM MNN ... ... ... ... ... ... ... ... :J::I

154J ,2' ...

'"1; CJ E

II>:J ...

J E N(7) CO 00 CO CONN .....MN MLn.....~(IJ(j : .......M N C')oov

...(7)..... LnvM N...O ....."

CJ Z VV NN N ... ... ... ... ... ... ... ... 04J

II>4J

... ..~..a. m E..~E

I E Ln~(7) CII'! 8 N V...Ln "'LnN .....(7)...

=.......

M ~N"'" V'-(7) ..... V MNNe!4D . U z V MN NN... ... ... ... ... ... ....."g ~..

ii :i

...

EC E :JC

i I E N co.........."'NOO ~~~(7)(7)0 E0

';:.......

M "'V(7) COMO VMM 'cu a. U Z v VMN NNN ... ... ... ... ... ...

'E::s..

...

"tI1;: c:J E ccJ E ..0 NLn..... vCOLn ........M MLnO IScofg ~N(7) .....LnM Eu ....... M(7)N OOLnM "'0(7) 00.......... Lnv vvv :J.. CJ Z VNN ... ... ... ... ...

E0'x

... ...

I I&. E ..E;

J E N...O OOOOLn ~""'LnN;gOO NLn... .....M...(7)~N II>(j ....... MM..... N(7)..... MN ... (7) (7)0000 ............... CO CO .cCJ Z vMN N...... ... ... ... ... ... .....

::::s...

>-0 w E~'0::.. I E NNOO OOOCO "'MOO CO..... (7) M........ .....MCD LnNO ";:;> u ....... MLn(7) CONO OOCOV MN... ...00 CD CD 00 000000

!II.. Z vMN NNN ... ... ... ... ... ... ... ... ...0 Q...

.....~... 0 EIII>l I E >

... NOv CD...(7) .....OON (7) CO..... ON CO Ovo Ln...OO ';:;4D .......M.....N 00 COM "'CDOO COLnv vMN N...... 00(7).. u f..

iZ vMM NNN N...... ... ... ... ... ... ... ... ... ... ... ......

ell ... cC U CJ E 15';: ! I EC')COCD II>

.. NO(7) .....0..... LnNN VCO(7) NCO... CON.....>iJ ,2'

.......MOOM OOOLn ...(7) 00..... CO LnvM MNN ......0U z ";:;u.!

VMM MNN NN... ... ... ... ... ... ... ... ... ... ... ... ... Ui::s0;;:: oS ...Q...

"i!m E

.!!0J E NNO OLnLn

CbC')~ MNN MMLn CDN(7) "'CO... x.. a ....... MOOLn NCD..... 0(7)00 .....COLn vvM MNN .Q. ~CJ Z VMM MNN NNN N...... ... ... ... ... ... ... ... ... ......E

'0.a

-.:i

...c.. c E J4D ~J E NNN MOO ~~~000..... ..........~ ON..... NLnO

::sii

....... M(7)CO M...(7) NO (7) 00..... COLnv VMM .g> a. CJ Z VMM MMN N N N NN... ... ... ... ... ... ... ... ... ...

I!!..:

II>.cN . .. I-4D <:S!. ui:g

clx 0(7)00 .....COLn VMN ... ... NMv LnCO..... 00(7)0 I-..

J...e"xii ":cici cicici cicici cioci cicici cicici cici": 0t- .fU)~

I I I I I I I I I I Z

BS 4465 : 19B9

Section two

*(f)*

31


9.9.2 If safety gears for either cages or counterweightsoperate on the guide rails, the latter shall be capable ofwithstanding the additional stresses produced by thebrak ing force using the factors given in 4.1.2.

9.9.3 Where a safety gear operates on the face of a guiderail, that face shall have a surface finish appropriate to thetype of safety gear.

Where vertical members of the mast or tower are used toguide the cage or counterweight and these members aremade of hollow sections, the wall thickness of the sectionsshall be designed to resist the most unfavourable combina-

Figure 6. Typical class E weld details

tion of the loads produced by the distribution givenin 10.1.2 and 10.1.3 all simultaneously applied, as follows:

(a) vertical load due to live load including impact;

(b) vertical load due to own mass of the structure;

(c) horizontal loads due to wind;

(d) horizontal loads due to cantilever moments of thecage or counterweight;(e) crushing loads due to the application, when fitted,of safety gear gripping elements to the sides of the mastmembers.

32

iiiii~iiiiiiiiii

*(f)

*

Figure 7 T .. VPlcal class F wel d d.

etalls


33


-0 -Tubular la ttice '-Class F

Angle lattice

Figure 8. Typical class F and class G weld details

34

iiii~iiiiiiii

*(J)

*

Figure 9. Typical class G weld details

35


Table 22. Size of perforation or opening in cageenclosure related to clearance

Maximum size of Minimum clearance fromperforation or opening" adjacent moving parts

mm mm

.;; 10 22

>10,.;;13 50

> 13,';; 32 100

> 32, .;; 38 125

* When the opening is in the form of a slot the length ofthe slot may be longer than this maxima, provided its widthdoes not exceed the maximum stated in the table.

BS 4465 : 1989Section three

Section three. Mechanical design and construction

10 Hoist cage and enclosure

10.1 Hoist cage

10.1.1 Basic construction. The hoist cage shall consistfundamentally of a frame which shall be designed tocomply with the permissible working stresses specifiedin 5.3 whilst carrying the loads given in 10.1.2 and 10.1.3.

10.1.2 Load distribution for persons. The area of the cagefloor shall be not less than 0.2 m2 per person, on the basisof each person weighing not less than 80 kg (i.e. 400 kg/m2).

10.1.3 Load distribution for materials. The design of thehoist shall take into account the fact that loads could besuch that their distribution will not necessarily be eithersymmetrical or uniform (see also clause 24(e) andclause 32(b)).

10.1.4 Floor. For hoists of 1000 kg rated load and over,the floor surface and supporting members shall be designedto carry wheel loads equal to 500 kg anywhere within anarea stated by the manufacturer (see clause 32(b)).

It shall be assumed that only one such load will occurwith in a floor area of 1.0 m x 0.5 m and that the area ofwheel contact is 150 mm x 40 mm.

10.2 Enclosure

10.2.1 The cage shall be roofed with imperforate panels.The sides of the cage unoccupied by the access gates shallbe enclosed to a height of not less than 1.98 m. Eachentrance shall be provided with an access gate, or door,extending to the full width of the cage opening and to aheight of not less than 1.98 m.

10.2.2 The cage enclosure and gates, or doors, shall becapable of withstanding a thrust of 350 N applied normallyat any position without permanent deformation andwithout the gates or doors being sprung from their guides.The 350 N thrust shall be applied by a rigid square flat faceof 50 mm whose edges are a radius of 3 mm.

10.2.3 Landing gate and cage threshold members shall bedesigned for a single vertical load of 40 % of the rated loador 500 kg, whichever is greater, and a single horizontalforce of 1500 N both applied centrally.

10.2.4 Solid doors, when fitted, shall be provided with avision panel located at eye level. This vision panel shall havean area not less than 250 cm2 and shall be shatter resistant.

10.2.5 The size of any perforation or opening in the cageenclosure and gates or doors, when closed, (including visionpanels) related to the clearances from adjacent moving partsshall be as given in table 22.

10.3 Cage/landing clearanceThe distance between the outside of the cage threshold andthe landing sill shall not exceed 45 mm.

10.4 Emergency egressAn opening for emergency egress shall be provided in theroof of the cage. The opening shall be provided with a coverthat opens outwards, shall only be operable from the inside

by means of a removable key and from the outside by apermanent handle. A safety switch complying with 22.7shall be provided to prevent movement of the cage whilstthe cover is not in place.

A ladder, giving access to the emergency opening, shall bepermanently available inside the cage.

The roof of the cage including the emergency opening shallbe protected by a railing consisting of an upper rail not lessthan 1 m above the roof, and an intermediate rail at half-height, and by a toe-board not less than 150 mm high.

10:5 Emergency audible alarm

In order that passengers may call for assistance from outsidean easily distinguishable and accessible emergency audiblealarm device shall be fitted within the cage. This device shallbe capable of being operated in the event of electricalsupply failure.

11 Hoistway enclosure and gates

Sufficient enclosure of the hoistway and counterweightshall be provided to protect persons from being struck bymoving parts of the hoist.

Gates shall be provided in the hoistway at every accesspoint.

The height of the enclosure and the gates shall be not lessthan 1.98 m above the landing floor.

The enclosure and the gates shall comply with 10.2.2to 10.2.4.

12 Interlocking of gates

12.1 Interlocks

12.1.1 Every gate shall be fitted with an effective electricaland mechanical locking device that complies with 12.2.

12.1.2 It shall not be possible under operating conditionsto open any landing gate from the landing side, or to open

36

a cage gate, unless the cage floor is within a :!:150 mm zoneof that particular landing.

12.1.3 It shall not be possible under operating conditionsto start or run the hoist, unless all gates (both cage andlanding) are within 20 mm of the closed position.

-iiiiii~

12.2 Locking devices

12.2.1 All locking devices shall be fastened securely andthe fastenings shall be restrained against working loose.

12.2.2 The locking elements shall engage fully by not lessthan 10 mm at right angles to the direction of motion ofthe part to be locked.

12.2.3 In the case of flap type locks the flaps shall overlapthe gate leaves over the entire width by an amountsufficient to prevent the gate from opening. It shall not bepossible for the locking flap to drop into the closedposition whilst the gate leaf or leaves are in any positionother than the closed position.

12.2.4 The electrical contacts in the gate locking devicesshall be opened positively and independent of gravity.

12.2.5 All gate locking devices, together with anyassociated actuating mechanism and electrical contacts,shall be so situated or protected as to be normallyinaccessible to persons from the landing. The devices shallalso be so designed that they cannot readily be madeinoperative by unauthorized interference with theirmechanism.

12.2.6 The locking devices shall be capable of resisting aforce of 1 kN at the level of the lock in the openingdirection of the gate.

12.2.7 Gate locking devices shall be designed to permitservicing. Electromechanical locks shall be encased andparts sensitive to water, deleterious dust and othercontaminants shall be contained within sealed housings.

12.2.8 The removal of any detachable cover shall notdisturb any of the lock mechanism or the wiring. Alldetachable covers shall be retained by captive screws.

12.2.9 The locking elements shall be held in the lockedposition by springs or weights. Where springs are used theyshall be in compression and adequately supported. Thefailure of a spring shall not render a lock unsafe.

*(I)*

13 Rope suspension

13.1 Cage and counterweight wire rope suspension orsupport

13.1.1 Not less than two wire ropes, independent of oneanother, shall be used for suspension. Means shall beprovided to ensure load equalization between the ropes.

13.1.2 The wire ropes shall be not less than 9 mm nominaldiameter in accordance with as 302 or as 329.

13.1.3 The working load on each rope shall be consideredas being a static load. The ratio of the minimum breakingload of each rope to this load shall be not less than 10 forcage suspension ropes or 6 for counterweight suspensionropes used with rack and pinion hoists.

as 4465 : 1989Section three

This ratio shall be obtained from the equation:

FnK- .. 10 for cage suspension ropesW

or

FnK- .. 6 for counterweight suspension ropes used withW rack and pinion hoists

where

F is the minimum breaking load of the rope;

n is the number of separate suspension ropes;

K is the roping factor, i.e. 1 for 1: 1 roping2 for 2: 1 roping3 for 3: 1 roping, etc.;

W is the maximum total static load imposed on theropes with the cage, and its rated load located in anyposition in the cage (including the mass of storedropes) .

NOTE. The minimum ratio is considered sufficient to take accountof the increase of load due to bending the rope and due to pulleybearing friction when the pulley, sheave and drum sizes are not lessthan those specified in 13.2.1.

13.1.4 Rope speeds shall not exceed 2 m/s.

13.1.5 Arrangements entailing reverse bends shall beavoided. Designs requiring surplus rope to be stored shallnot use rope connectors or fittings liable to cause damageto a section of rope that could subsequently become partof the system.

13.1.6 The strength of the rope terminations shall be notless than 80 % of that of the ropes.

13.2 Drums, traction sheaves and pulleys

13.2.1 Minimum diameter. The diameter of drums, sheavesand pulleys shall be 30d (where d is the nominal diameter ofthe rope). measured at the bottom of the groove. In thecase of a vee or undercut drive traction sheave the minimumdiameter shall be 31d at the pitch circle diameter of therope in the groove.

13.2.2 Angle of fleet. The angle of fleet between the ropeand a plane normal to the axis of a pulley shall not exceed2.50, as shown in figure 10.

Maximum angle of fleet

-+-

Pulley

=~:

Drum

Figure 10. Angle of fleet

37

Table 23. Clearance between turns of ropeon helically grooved drums

Clearance Nominal rope diamater

mm mm

~1.6 .. 13

~2.4 .. 28


The lead off angle from drums shall not be greater than 2.50when grooved, or 1.50 when plain, measured each side of aline normal to the axis of the drum.

In the case of traction sheaves the lead shall not deviate bymore than 2.50 from a plane normal to the axis of thesheave groove.

13.2.3 Drum and pulley grooves

13.2.3.1 General. All grooves shall be smoothly finishedand their edges rounded. The contour of the groove shallbe circular over an arc of not less than 1200 and have aradius of not more than 7.5 % nor less than 5 % in excessof half the nominal diameter of the rope.

13.2.3.2 DrumNOTE. The requirements of this subclause do not preclude the useof drums having grooves of non-helical form.

Helically grooved drums shall have a groove depth not lessthan 1/3 the nominal diameter of the rope and shall bepitched so that there is clearance between neighbouringturns of rope on the drum. There shall also be clearancebetween the part of the rope leading on to, or leaving, thedrum and the adjacent turn.

The clearance between neighbouring turns of rope on ahelically grooved drum shall be as given in table 23.

Drums shall be flanged at both ends, When the rope is fullywound onto the drum the flanges shall project for adistance equivalent to not less than two rope diameters;this projection shall be not less than 25 mm. An overspillswitch complying with 22.6 shall also be fitted.Rope anchorages shall be protected by not less than threedead turns remaining on the drum when the rope is paidout to its maximum working length. The anchorages shallbe designed to withstand the maximum working load onthe rope (see 13.1.3) making no allowance for the effectof any dead turns.

13.2.3.3 Pulleys. Pulleys shall have a groove depth not lessthan 1.5 times the nominal diameter of the rope. The angleof flare on the sides of the groove shall be 520.

13.2.4 Traction sheave grooves. The rope grooves intraction sheaves shall take one of the following forms.

(a) Round: in which the groove is a circular arc having aradius not greater than 5 % larger than half the nominaldiameter of the rope and has a depth not less than 1/3of the nominal diameter of the rope.(b) Round undercut: in which the groove is the same

as (a) but undercut.(c) Vee: in which the straight sides subtend an included

angle of 37.5 :t 2.50.

14 Rack and pinion suspension system

14.1 GeneralThe rack and the pinion shall be manufactured inaccordance with the dimensional requirements ofas 436 : Part 2 and designed in accordance withas 436 : Part 3; the metric module shall be not less than 7.

14.2 Driving pinionThe driving pinion shall be machined from a material thatwill resist wear and provide a safety factor of not lessthan 6. Undercutting of the teeth shall be avoided.The pinion shall be affixed to the output shaft inaccordance with 15.10.

14.3 Racks

The racks shall be made of material having propertiesmatching those of the pinion in terms of wear and impactstrength, and shall possess an equivalent safety factor.

The racks shall be securely attached to the mast or tower,particularly at their ends. Joints in the rack shall beaccurately aligned to avoid faulty meshing or damage toteeth.

The load imposed upon the rack by the pinion shall notcause permanent deformation of the rack.

14.4 Rack/pinion engagementMeans shall be provided to maintain the rack and the pinionconstantly in mesh under all conditions of load. Such meansshall not rely upon the cage guide rollers. The devices usedshall restrict movement of the pinion on its axis such thatat least two-thirds of the tooth is always in engagementwith the rack. In addition it shall not be possible for thepinion to move out of its correct engagement with the rackby more than one-th ird of the tooth height.

14.5 GuardingSubstantial guarding shall be provided to prevent the entryof any material that might cause damage to the rack orpinion.

15 Driving machinery

15.1 Each hoist cage shall have at least one individualdriving machine fitted with a brake which operatesimmediately to arrest the cage when the operating orsafety circuit is broken.

15.2 If two or more mechanically separate drives are used,each drive shall have its own independent brake.

15.3 The drive motor shall be coupled to the drum, drivesheave or drive pinions by a positive drive system thatcannot be disengaged.

15.4 The cage shall, during normal operation, be raisedand lowered under power at all times.

15.5 Driving machinery and associated equipment shall beso positioned or guarded to protect persons from injury.Any machine enclosure door or gate shall be provided witha lock.

The machinery and equipment shall be readily and safelyaccessible for servicing and examination. It shall also bereasonably protected against damage from falling objects.

15.6 Chains and chainwheels shall comply with BS 228.The chainwheels shall be of cast iron or steel, have aminimum of 25 machine cut teeth and have a minimum of6 teeth in engagement. Means shall be provided to preventthe chain from leaving the chainwheel and riding over theteeth.Use may be made of belts for coupling the motor or motorsto the component on which the electromechanical brakeoperates.

A minimum of two belts, complying with BS 3790,shall be used.

15.7 All gearing shall be class 9 or 10 in accordance with:(a) BS 436 : Parts 2 and 3, for spur gears; or

(b) BS 545 for bevel gears; or

(c) BS 721 : Part 1 or Part 2 for worm gearing;as appropriate.

15.8 Stress concentrations shall be minimized by formingadequate fillets where shafts and axles are shouldered.Pulleys or sprockets and their shafts shall be so supportedand retained as to prevent them from becoming displaced.

15.9 Keys shall be effectively secured against movement.

15.10 Any separate sheave, rope drum, spur gear, wormwheel or brake drum shall be fixed to its shaft or otherdrive unit by one of the following methods:

(a) sunk keys;

(b) splines or serrations;

(c) secured by means of machined fitting bolts to aflange forming an integral part of the shaft or drivingunit.

15.11 Bearings shall be of the ball, roller, sleeve or otherreplaceable type.

Ball and roller bearings shall be arranged in dust-proofhousings and shall be adequately lubricated.

Sleeve bearings having ring or chain lubrication shall haveample reservoirs, provided with drain plugs and means toascertain and limit the level of oil in the reservoir.Gear cases shall be provided with journal and thrustbearings to suit the application.

Where access to a bearing for lubrication would otherwisebe difficult provision shall be made for remote lubrication,or for safe access to the lubrication point.

15.12 The brake, motor, gear case and any bearings shallbe mounted and assembled so that proper alignment ofthese parts is maintained under all conditions.

*en*

16 Brake

16.1 The hoist shall be provided with a braking systemthat operates automatically:

(a) in the case of loss of the power supply;

(b) in the event of the loss of the supply to the controlcircu its.


16.2 The brake shall be capable of bringing the hoist cageto rest under maximum conditions of load and speed andmaintaining the cage stationary when fully loaded.

16.3 No toggle or positive locking device shall be used tohold off the brake. The brake shall not be released innormal operation unless power is applied to the hoist motor.

16.4 Compression springs shall be used to apply the brake.They shall be adequately supported and shall not be stressedin excess of 80 % of the torsional elastic limit of thematerial.

16.5 In the case of drum brakes a minimum of two shoesshall be used. Brake linings shall be of incombustiblematerial and shall be so secured that normal wear will notweaken their fixings. The wearing surfaces of brake drumsand discs shall be machined and shall be smooth and freefrom defects.

16.6 No earth fault, circuit malfunction or residualmagnetism shall prevent the brake from being appliedwhen the power supply to the hoist motor is interrupted.

16.7 Means of releasing the brake in an emergency shall beprovided and ensure the immediate reapplication of thebrake as soon as hand pressure is released.

16.8 The brake shall be designed to prevent the ingress oflubricants, water, deleterious dust or other contaminants.

16.9 Brakes shall be provided with means of adjustment.

17 Counterweights

17.1 Counterweights shall not be used with winding drummachines.

17.2 The hoist cage shall not be used to counterbalanceanother hoist cage.

17.3 If the counterweight incorporates filler weights,one of the following measures shall be taken to preventtheir displacement:

(a) the fillers shall be retained within a frame; or

(b) if the rated speed of the cage is not greater than1 mis, metallic fillers shall be restrained by a minimumof two tie rods.

17.4 To prevent the displacement of counterweights fromtheir guides the guides shall be equipped with a permanentanti-disengagement device in addition to rollers or shoes.

17.5 Counterweights shall be guided by suitable shoes orrollers situated near the upper and lower extremities of thecarrier frame.

17.6 Allowance shall be made for counterweight overrunat the top end of the hoistway.

17.7 A notice shall be displayed stating the total mass ofthe counterweight required and each individual block shallhave its own mass marked on it.

39

Table 24. Type of safety gear for counterweights

Type of safety gear < 1.0 m/s > 1.0 m/s

Instantaneous J

Progressive J J

Table 25. Governor tripping speeds

Rated speed Tripping speed max.

mls

< 0.63 1.0 mls

> 0.63, < 1.2 1.4 X rated speed

> 1.2 1.3 x rated speed

NOTE. Under extreme conditions, for example very lowspeeds and very high loadings, a lower tripping speedmay be adoPted.


18 Safety gear

18.1 Every hoist shall be provided with a safety gear ofthe progressive type attached to the cage frame andactuated by a governor.

18.2 The safety gear shall be tested and certificated inaccordance with 31.2 and shall be permanently markedwith the following data:

(a) maker's name;(b) model number;(c) serial number;

(d) governor tripping speed;

(e) maximum stopping distance.

18.3 Counterweights on traction drive machines shall alsobe fitted with a safety gear.

18.4 The safety gear shall operate with a deceleration notexceeding 10n to arrest and support the cage with itscontract load, in the event of any failure of the hoist whichresults in the rated speed being exceeded other than astructural failure of the mast (see clause 19 and item 19 ofappendix A).

18.5 The safety gear and governor shall be operationalduring erection and dismantling work.

18.6 The motor control and brake control circuits shall beautomatically opened by a switch on the safety gear beforeor at the time the safety gear is applied.

18.7 When the safety gear has tripped it shall not bepossible to release or reset the safety gear by raising thecage or platform by means of the normal control.

18.8 No safety gear shall be dependent for its operation onenergizing or maintaining an electrical circuit.

18.9 Pulleys used to carry governor ropes shall be mountedindependently of any shaft that carries the suspension ropepulleys.

18.10 If a safety gear is fitted to the counterweight thetype of safety gear shall be as given in table 24.

18.11 When the safety gear is of the rack and pinion typeit shall also comply with clause 14.

18.12 Where there is relative movement between thegripping and the braking surface, these surfaces shall be/:Ield clear of each other during normal operation of thehoist.

18.13 A safety gear designed to grip more than one guideshall operate on all guides simultaneously.

18.14 Safety gears shall not operate to stop an ascendinghoist cage. If an ascending hoist cage is to be stopped onaccount of overspeed, then a safety gear shall be fitted tothe counterweight for this purpose.NOTE. An overspeed governor may however be used to cause themotor control and brake control circuits to be opened in the eventof overspeed in the upwards direction.

18.15 Suitable provision shall be made to prevent thesafety gear from becoming inoperative due to theaccumulation of extraneous matter or to atmosphericconditions.

18.16 Where safety gear of the gripping type is fitted onthe cage or the counterweight, no component of the safetygear shall be used for both guiding or braking.

18.17 In safety gear where the action is achieved by meansof coil springs, the springs shall be in the form ofcompression springs which shall be guided and in thenon-loaded condition have a coil pitch of less than twicethe wire diameter.

19 Overspeed governors

19.1 Governors shall come into action and trip the safetygear before the hoist cage reaches a speed exceeding therated speed by the amount given in table 25.

19.2 The device that sets the tripping speed of the safetygear shall be located, as far as possible, to preventunauthorized alteration. The correct tripping speed shallbe marked on the safety gear.

19.3 Ropes and rope attachments, etc. to governors shallbe dimensioned and designed in accordance with 13.1.

The nominal diameter of the rope to the governor shall benot less than 8 mm and the bending diameter shall be atleast 30 x the nominal diameter of the rope for pulleysidling in normal service. Pulleys and drums that rotate onlywhen the safety gear operates shall have a diameter of atleast 15 x the nominal diameter of the rope,

20 Buffers

The travel of the hoist cage and counterweights shall belimited at the bottom by buffers that are designed in such

40

a way that the deceleration of the cage does not exceed19n. For this purpose it shall be assumed that the buffersstop the cage from governor tripping speed.

21 Hoist cage overrun

21.1 The hoist cage shall operate the ultimate limit switchbefore striking the buffers.

21.2 In all cases the minimum distance between thebottom landing level and the ultimate limit switch shall besuch that the latter is not operated during normal serviceoperation.

21.3 The overrun of the hoist cage at the top end of thehoistway, i.e. the vertical distance the cage may travel afteroperating the ultimate limit switch and before meeting anyobstruction to its normal travel or upper guide rollersreaching the end of the guides, shall be not less than:

(a) 0.15 m on hoists operated by rack and pinion;(b) 0.5 m on hoists operated by wire ropes.

When operating at rated speeds (v) greater than 0.85 m/sthe above overrun shall be increased by 0.1 v2 m.

22 Safety switches

22.1 General

22.1.1 All the safety switches described in this clause shallbe of the positively operated type and shall not be depend-ent upon springs for their operation.

22.1.2 The enclosure for safety switches shall beweatherproofed in accordance with clause 27. Theenclosures and their frames, brackets, etc., shall be earthedin accordance with clause 28.

22.1.3 When a safety switch forms part of the electricaland the mechanical interlocking of hoistway and hoistcagegates, the safety switch shall be mechanically coupled sothat it cannot close the circuit whilst the gate is open.

*(J)

*

22.2 Terminal stopping switchesStopping switches shall be fitted to each hoistway or hoistcage and shall be positively operated and of the self-resetting type, so arranged that their operation will resultin the hoist cage being automatically stoppped from anyspeed attained in normal operation within the overall travelrange of the cage.

22.3 Ultimate limit switchesUltimate limit switches shall be fitted within the hoistwayor to the hoist cage and shall be positively operated and beof the non self-resetting type. The switches shall be soarranged that in the event of the cage overrunning theterminal stopping switches, they will interrupt the mainpower supply to the hoist motor and electromechanicalbrake on all phases. The switches shall be directly operatedby movement of the cage.

NOTE. In the caseof traction driven hoists the switches may beoperated directly by the counterweight.


22.4 Terminal slowing switchesWhen the hoist drive is of the multi-speed type, a set ofslowing switches shall be fitted at the terminal landings.These switches shall be of the self-resetting type, arrangedso as to decelerate the hoist cage to the minimum speedprior to the cage reaching the terminal stopping switch.This function shall be performed independent of theposition of the control in the hoist cage.

22.5 Slack rope switches

A non-resetting slack rope switch shall be fitted on:(a) hoists utilizing a winding drum; and

(b) counterweighted rack and pinion hoists,

arranged to interrupt the control circuit of the controlequipment in the event of any rope becoming slack.

22.6 Overspill switch

A non-resetting switch shall be fitted that will stop thewinding motion and apply the brake should any part ofthe rope wound onto the drum project by more than halfthe rope nominal diameter above the drum flange.

22.7 Cage roof access door switchThe switch specified in 10.4 shall be so positioned that anymovement to open the cage roof emergency door duringnormal operation of the hoist would result in the controlcircuit of the hoist being interrupted.It shall not be possible to override this switch from insidethe cage.NOTE. Provision may be made to short circuit this switchspecifically for the purposes of inspection and erection when thehoist control is transferred to the roof of the cage. In the interestsof safety this provision should not be used to facilitate the carriageof long loads.

23 Guarding

23.1 General

Effective guards shall be provided for gear wheels, belts andchain drives, revolving shafts, flywheels, couplings, collars,projecting set screws, and bolts or keys on any revolvingshaft, wheel, or pinion, unless those parts are made safe bydesign or by position, or are effectively guarded by partsof the structure.NOTE. In appendix A reference is made to statutory obligationsaffecting hoists when used for building operations and works ofengineering construction in the United Kingdom.

23.2 Design of fixed guardsGuards shall be of sheet metal (perforated or expanded),wire mesh, wood, or other suitable material and shallcompletely encase the moving parts concerned. The guardsshall be designed to permit easy access for routine inspec-tion and maintenance work. Guards shall be substantiallyconstructed to withstand the atmospheric conditions inthe environment in which they are used, and shall besufficiently rigid to resist distortion. Guards shall besecurely attached to a fixed support.NOTE. Guidance on the design of guards is given in BS 5304.

41


The thickness of metal guards shall be not less than1.25 mm.

The minimum clearance between the guards and movingparts, and the size of the opening in guards or perforatedmetal, woven wire, metal lattice, or similar material shallbe in accordance with BS 5304.

24 Notices

Each hoist cage shall have permanently fixed in aprominent position a legible and permanent plate or platescarrying the following information.

(a) The manufacturer's name and address.

(b) The model and serial number of the hoist.

(c) The year of manufacture of the hoist.

(d) For rope suspended hoists, the nominal diameterand specification of the suspension rope.

(e) The rated load of the hoist, in kilogrammes, anddetails of any limitations on the positioning of loads.(f) The maximum number of persons that it ispermissible to carry in the hoist cage and whether thisincludes the driver.(g) Information on whether it is necessary to reducethe rated load at extreme heights.(h) Bolt material specification.

NOTE. It is dangerous to use bolts other than those specifiedby the hoist manufacturer.(i) The mass of the counterweight, if fitted.(j) A warning that persons trapped in the cage shouldremain in the cage until released under the instructionof a competent person.(k) The rated speed.

42

BS4465 : 1989Section four

Section four. Electrical design and constructionNOTE. In drafting this section it is assumed that the electrical installation complies with thelatest edition of the lEE Regulations for Electrical Installations.

25 Mains supply isolating switch

25.1 For each hoist there shall be a manually operatedisolating switch or circuit breaker capable of isolating everypole of the supply network. The switch or breaker shall becapable of disconnecting the hoist motor starting current.

25.2 The isolating switch shall be positioned in an easilyaccessible position. Where this switch is housed in a cabinet,the operating handle shall be accessible outside the cabinet.

25.3 The handle shall open the contacts positively and thehandle shall be lockable in the off position.

25.4 The positions of the switch shall be clearly marked'off' and 'on'.

26 Cables and wiring

-

26.1 The size of all cables supplied with the hoist shall besuch that the rating is adequate for the maximum currentto be carried under all conditions of operation in service,including starting.

26.2 The mains cable for connecting the hoist to thesupply network shall be such that the rating and sizecomplies with 26.1.NOTE. Protection should be provided by suitable fuses or a circuitbreaker in accordance with the hoist manufacturer'srecommendations.--!!!!!!!

*[J)

*

26.3 All cables and wiring for the hoist shall be locatedand installed to provide maximum protection frommechanical damage that may be caused during the use ofthe hoist.

26.4 Terminals shall be adequately shrouded and incomingpower terminals shall be covered and marked 'Liveterminals'.Power and control circuits shall be grouped and, wherenecessary, separated by insulating barriers; they shall alsobe marked according to the designation of the circuits.

26.5 When positioning a cable, allowance shall be made forthe stresses to which the cable can be subjected as aconsequence of mechanical action. When the cable is led into motors, apparatus, connection boxes, etc., this shall bedone in an appropriate manner for each type of cable andin such a way that the cable is protected against the stressesoccurring.

Trailing cables and flexible cables shall be protected againstwear, breakage or tearing. The outer sheath of the cableshall be led in and securely fixed at the lead-in point so thatthe cores are not subjected to harmful tension or twistingin the connection space. Normal sealing glands withpackings are not regarded as meeting the requirement forrelief from pulling and twisting.

Cables shall be connected and branched in permanently-mounted enclosed terminal blocks or by means of strongconnectors intended for the purpose. Loose clamps orjointing of cables, e.g. flexible cables, in any other mannerthan by means of the devices intended for the purpose,shall not be used.

26.6 Precautions shall be taken to ensure the free and safemovement of the cage trailing cable throughout the fullrange of travel of the hoist cage.

26.7 If there is a requirement for contactor cabinets,limit switches or push-button enclosures to be heated,the supply for this heating circuit shall be connected to thelive side of the isolating switch. These conductors shall notbe contained within the same sheath as other wires,Disconnection of the heating circuit shall be by means of aseparate switch marked 'electrical heating' which is situatedadjacent to the supply isolating switch described inclause 25. All live parts of the heating circuit shall beshrouded and identified.

26.8 The control gear cabinet shall contain such drawingsor documentation as are necessary to aid electricalmaintenance and fault finding, e.g. a circuit diagram and awiring diagram.

27 Protection against the effects ofexternal influences

All electrical apparatus excluding that installed in controlgear cabinets shall be protected from the harmful orhazardous effects of external influences, and whereappropriate to the design, positioned to provide protectionagainst rain, snow, mortar, concrete, dust and other dirt,i.e. have a degree of protection at least equal to that whichcorresponds to the symbol IP54 as classified in BS 5490.NOTE. The Index of Protection liP) Code, is expressed in the form'IPXX' in which a numeral replaces an X. The first digit definesdegrees of protection against contact with live or moving parts andprotection against ingress of solid bodies, and the second digitdefines the degree of protection against ingress of liquid. Fullinformation on degrees of protection offered by enclosures is givenin as 5490.

28 Earthing

The hoist structure, motor frames and metal casings of allelectrical equipment, including metal cabinets, conduit andguards, shall be effectively bonded to earth.

29 Control circuits, panels, equipment andsystems

NOTE. Guidance on the design of control systems in general isgiven in as 5304.

29.1 Control circuits

29.1.1 Provision shall be made for a reasonable time lagbetween the stopping of the hoist cage and its beingresta rted.

29.1.2 The voltage of the hoist control and operatingcircu its shall not exceed 130 V with respect to earth andshall be connected to the alternating current network viaan isolating transformer with separate primary andsecondary windings and with the primary windings earthscreened.

43

as 4465 : 1989Section tau r

One pole of the secondary winding, or if a rectifier isconnected to it one d.c. pole, shall be directly connectedto earth.

29.1.3 Control circuits shall be so arranged that any fault,except open circuit faults, will be faults to earth. Anyfaults, or the discharge or failure of any circuit component,shall not set up an unsafe condition, e.g. starting orcontinuing cage motion when any safety contact hasopened or is opening.

29.1.4 All safety circuits shall be designed to prevent anintercircuit fault.

29.1.5 Control circuits shall be protected by fuses or equiv-alent devices, independently of the protection provided forthe main circuits. In the event of an earth fault in thecontrol circuit of the hoist, the circuit shall be disconnectedas a result of rupturing a fuse or similar protective device.

29.1.6 Switches shall not be connected between the earthand the control circuit operating coils.

29.1.7 The opening of the circuit to stop the hoist at theterminal floors shall not be dependent upon the directoperation of a spring (see 22.1.1) or upon the completionof another electrical circuit.

29.1.8 The control system shall not depend uponenergizing or maintaining the continuity of an electricalcircuit for the interruption of the power supply to thehoist motor and the application of the machine brake tostop the cage when any safety switch (see clause 22) isoperated.

29.2 Electrical control panels and cabinetsNOTE. BS 5486 : Part 1 specifies general requirements for factorybuilt assemblies.

29.2.1 Panels and cabinets shall be of robust constructionand shall be protected in accordance with clause 27.

29.2.2 The cabinets shall be designed and located such thatwhere practicable an unobstructed working space of notless than 1 m deep and 1.90 m high is provided for accessfor maintenance and inspection in front of the door orcover.

29.2.3 To prevent unauthorized access during normal useof the hoist, doors or covers that are provided formaintenance and inspection shall be secured by devicesthat require a spanner, key or special tool to remove orloosen them. Should threaded fasteners be used they shallbe of the captive type.

29.2.4 If the mains supply isolating switch specified inclause 25 is not housed in the control gear cabinet, a labelshall be permanently displayed on the outside of the dooror cover of the cabinet requiring the mains supply to thecabinet to be moved to the 'off' position before openingaccess doors or covers.

29.3 Control equipment, relays and contactors

29.3.1 The control equipment shall be adequatelyprotected to prevent accidental contact with live parts.

29.3.2 Controller panels or their supporting frames shallbe constructed of materials that do not supportcombustion.

29.3.3 Main and auxiliary resistors shall be adequatelysupported and ventilated.

29.3.4 Interlocking shall be provided, where necessary,to ensure that the relays and contactors operate in propersequence.

29.3.5 Contactors for reversing direction of travel shall bemechanically and electrically interlocked.

29.3.6 Where contactors having metal to metal contactsare employed to open a circuit in order to stop the hoistdrive, such a circuit shall have at least two independentcontactors to afford double break of one or more mainlines. For three-phase systems the main contactor shall betriple-pole and switch all three phases.

29.3.7 Each hoist motor shall be protected fromovercurrent.

29.3.8 Hoists connected to polyphase a.c. power suppliesshall incorporate means to prevent the motor beingenergized in the event of a phase failure or phase reversal.

29.4 Manual controls

29.4.1 Type of controls. The hoist controls, includingtemporary controls (such as on the cage roof, see 29.4.3),shall be so arranged that control can be effected from onelocation only at anyone time.

29.4.2 Cage controls. Controls located inside the cageshall be placed in a position:

(a) which will give the operator ample room foroperation and a clear view of the landing levels; and(b) that it is impossible to reach them by hand fromoutside a closed landing gate.

Every cage operating device shall be arranged to return tothe 'stop' position when released.

29.4.3 Cage roof control. If any maintenance, inspectionor erection requires the presence of persons on the hoistcage roof whilst the cage is in motion, a control stationshall be provided on the cage roof. This control shall, in thecase of multi-speed installations, only permit movement ofthe cage at low speed.

29.4.4 Cage roof safety control. A non self-resetting switchshall be provided on the cage roof, which at all times shallbe capable of stopping and preventing movement of thecage.

29.4.5 Remote control. Remote control facilities shall beprovided only to facilitate testing.

29.4.6 Operators' key switch. A switch to render thecontrol circuit inoperative shall be fitted in the cage as ameans of preventing unauthorized operation of the hoist.The switch shall be of a type that cannot be turned to the'on' position until a key has been inserted, the key beingtrapped when turned and not removable until returned tothe 'off' position.

44

29.4.7 Marking. All manual controls shall be clearlymarked to indicate their purpose and the direction oftravel resulting from their operation.

29.5 Non-conductive control system

29.5.1 When used, a non-conductive control system shallbe applicable to the control of the cage only and shall notbe used for any part of the landing gate interlock system.In addition to the relevant requirements elsewhere in thisstandard, the requirements given in 29.5.2 to 29.5.8 shallalso apply.

29.5.2 All cage safety interlocks shall be so arranged thatin the event of any interruption of the safety circuits itshall not be possible for any movement of the cage to takeplace.

29.5.3 The signal level shall be such that malfunction dueto the imposition of spurious signals shall not occur.Frequencies used by local radio, television and h.f. heatersshall be avoided.

29.5.4 Failure of any relay or relay circuit to operateproperly shall not give rise to potentially unsafe conditions,e.g. movement of the cage with the gates open.

iiiii~iiiiiiiiii

*(f)

*

as 4465 : 1989Section four

29.5.5 Any variation of supply voltage to component partsof the installation shall not give rise to unsafe conditions.

29.5.6 The wiring arrangements for the installation shallbe such that control circuit wiring and connections areadequately segregated from other supplies.

29.5.7 All safety switches (see clause 22) shall operateindependently of the non-conductive control system.

29.5.8 It shall be possible to check and test the functionof cableless control units on site without energizing themain hoist motor control gear.

30 Suppression of radio and televisioninterference

All circuits and electrical equipment shall be designed tocomply with as 800 to prevent giving rise to radiointerference in excess of local regulations.The necessary components used to provide the requireddegree of suppression shall not be used in any part of thecircuit where their failure might cause an unsafe condition.

45

as 4465 : 1989Section five

Section five. Testing

31 General

31.1 General

All hoists shall be submitted to the following tests:(a) safety gear type tests (including governors) (see 31.2);

(b) prototype proof tests (see 31.3);

(c) production tests (see 31.4).

31.2 Cage safety gear type tests

31.2.1 A representative model of every new version ofsafety gear shall be tested to apply stresses to all partsequivalent to those resulting from drop tests loaded inaccordance with tables 2 and 3.

31.2.2 The tests shall be conducted at the governortripping speed specified by the hoist manufacturer andutilizing the design of mast or tower and/or rack whichwould normally be employed in normal service.

31.2.3 The total number of repeated tests shall be not lessthan the number calculated from the following, subject toan absolute minimum of 100 tests:

minimum number of tests = 2No Ld

where

No is the average expected number of operations of thesafety gear per year, subject to a minimum of 10operations;

Ld is the design life of the safety gear, in years.NOTE. The design life Ld of the safety gear may not necessarilybe that of the complete hoist unit.

31.2.4 For rack and pinion hoists at least 10 % of the testsshall be conducted with the drive pinion disengaged and inat least 10 % of the tests the pinion shall be engaged.

NOTE. Attention is drawn to the additional requirements ofHealth and Safety Executive Certificate of Exemption CON/I-O/S1 11which applies to certain rack and pinion hoists.

31.2.5 The stopping distance during all tests shall be notgreater than the specified maximum.

31.2.6 Upon completion of the test programme acertificate of test in accordance with appendix G shall beproduced and completed.

31.3 Prototype proof tests

31.3.1 The hoist manufacturer shall submit the firstcomplete hoist of any new design to a proof loading testof 150 % the rated load evenly distributed over the cageplatform and 125 % of the rated load placed at themaximum eccentric positions in each direction asdetermined in accordance with 10.1.3.

31.3.2 Each test shall consist of at least 10 full height runsup and down a mast that has been erected to themanufacturer's maximum free standing height.

31.3.3 Although the full rated speed need not be attainedduring the tests it shall be demonstrated that the hoist iscapable of operating satisfactorily with 150 % of the ratedload.

31.3.4 A further test shall be carried out by themanufacturer to demonstrate that the safety gear is capable

of arresting the motion of the cage when containing 125 %of the rated load under the conditions specified in 31.3.1whilst descending at the safety gear tripping speed.

31.3.5 On completion of the above type tests the hoistshall be thoroughly examined and shall be found to befree from defect.

31.3.6 On counterweighted hoists employing tractiondrives it shall be demonstrated that the hoist drive willmaintain traction throughout normal operating travelof the cage in both directions whilst the mass of thecounterweight is reduced by 50 % and the rated load onthe cage platform is reduced by an equivalent amount.

31.4 Production tests

31.4.1 General. Every production hoist shall be submittedto the production tests given in 31.4.2 to 31.4.5 by themanufacturer.

31.4.2 Functional tests. The hoist shall be operated inboth directions at such minimum height as will allowadequate testing whilst the cage contains:

(a) the rated load, evenly distributed over the platform;and(b) 125 % of (a).

Although the full rated speed need not be attained duringthe overload test (b) it shall be demonstrated that the hoistis capable of operating satisfactorily with the overload.NOTE 1. The functional test may be carried out by themanufacturer at his works or on site as part of his site testingprogramme.

NOTE 2. The necessity for subsequent repetition of certain tests inorder to comply with statutory requirements is not precluded.

31.4.3 Safety devices. All safety devices shall be tested todetermine that:

(a) the overspeed device operates at the rated speed;

(b) the safety gear is capable of arresting motion of thecage without the assistance of any motor brakes andwithin the manufacturer's declared stopping distancewhen the cage contains the rated load as it is descendingat the tripping speed of the governor;(c) operation of the terminal stopping switches causesthe cage to stop within the limits of overtravel for thecage, and the counterweight if fitted;(d) when the terminal stopping switches are overrun,the ultimate stopping switches will operate and cut offthe power supply to the machinery on all phases;(e) the mechanical and electrical interlocks of all cageand landing gates and doors function correctly.

31.4.4 Electrical tests

31.4.4.1 Brake operation. Checks shall be made to ensureproper release and arrest functions of the brake at its ratedcurrent and voltage.The brake shall also be checked for correct adjustment andthat the brake arrests the motion of the cage during thefunctional tests given in 31.4.2.

31.4.4.2 Insulation resistance. Before the hoist is connectedto an electrical supply the insulation resistance shall bemeasured between all leads in the power lines and earth and

46

BS 4465 : 1989Section five

all control lines and earth. The insulation resistance shall benot less than 1 kD.N in circuits carrying more than 50 V,with a minimum value of 0.25 MD.. The test shall be madewith a megger applied to all applicable parts of the circuitsso as to ensure that the hoist is correctly earthed. Circuitscontaining electronic components, instruments, timers,rectifiers, etc., shall not be subjected to this test.

31.4.5 Other tests and checks. To detect faults in materialsand workmanship, tests and visual checks shall be made toascertain that:

(a) all mechanical elements such as interlocks, locksand enclosures are effective;(b) conductors and cables are laid correctly;(c) devices are mounted correctly;

(d) cable connections are tight and have adequatecontact;(e) all interlocks, sequence controls and safety interlocksare wired and function correctly;(f) the earthing of all metal frames for motors, safetyswitches, control switches, cabinets and hoist structureis continuous and not greater than 0.1 D. impedancewith respect to the main earthing terminal.

iiiiii!!!!!!!

*(I)*

47

as 4465 : 1989Section six

Section six. Instruction manual

32 General

Eachhoist shall be supplied with an instruction manualwhich provides technical data concerning the hoist,examples of which are listed below.

(a) The type and model.

(b) The capacity of the cage, giving both the number of

persons, the rated load (in kg) and the positions ofpermissible loads (see 10.1.2 and 10.1.3).(c) Hoisting speeds (in m/s).

(d) The internal dimensions of the cage, Le. width,

length and clear height (in mI.(e) The access width into the cage (in mI.

(f) The minimum mast height required above the top

landing.(g) The minimum distance (in mm) between the lowestlanding and the lowest point of the hoist structure.

*(h) The maximum overall height of the mast (in mI.

*(i) The maximum spacing of ties to the supportingstructure (in mI.

*(j) The maximum free standing height of the complete

hoist (in m) (to comply with IN SERVICE andQUT-QF-SERVICE conditions).

*(k) The maximum permissible height (in m) of the

mast or tower above the top tie.(I) A description of the drive unit, e.g.:

(1) power (in kw);

(2) electricity supply (in V, Hz and phases);

(3) full load current (in A);

(4) starting current (in A).

(m) The type of brake.

(n) A description of the driving unit.

(0) The type and position of the control.

(p) The type of landing gate (e.g. rising or outwardopening).(q) Suspension rope details (where applicable):

(1) number;

(2) construction;

(3) diameter;

(4) minimum breaking load;

(5) number of falls;

(6) ratio of minimum breaking load/rated load.

(r) Installation details of terminal and ultimate

stopping switches.

(s) Full information on the operation and maintenance

of safety gear, including method of assessing wear.(t) Full information for the installation, testing,

operation, extension, servicing and dismantling of thehoist.(u) Full information to enable foundations, ties and tie

fixings to be designed in relation to the four scheduledzones of operation.(v) Specification of bolts for assembling the structure.

(w) An electrical circuit diagram showing the operation

of the electrical equipment (in the ready for service stateand switched off).

.The dimensions required by (h), iii, (j) and (k) should be selected from table 4 to suit the zone of operation. For operation outside thefour scheduled zones, or for special applications, the hoist manufacturer's recommended figures should be stated.

48

Appendices

Appendix A. Legislation and relateddocuments

iiiiii~iiiiiiiiiiii

The following legislation and documents may be applicableto electric hoists in the United Kingdom.

1. Health and Safety at Work etc. Act 1974.

2. Factories Act 1961.

3. The Lifting Machines (Particulars of Examinations)Order 1963.5.1. 1963 No. 1382.

4. Ship Building and Ship Repairing Regulations,5.1. 1960 No. 1932.

5. The Construction (Lifting Operations) Regulations5.1.1961 No.1581.

6. The Construction (Lifting Operations) CertificatesOrder, 5.1. 1962 No. 227.

7. The Construction (Lifting Operations) Certificates(Amendment) Order, 5.1. 1964 No. 531.

8. The Construction (Lifting Operations) Reports Order,5.1. 1962 No. 225.

9. The Construction (Lifting Operations) PrescribedParticulars Order, 5.1. 1962 No. 226.

10. The Construction (Lifting Operations) PrescribedParticulars (Amendment) Order, 5.1. 1962 No. 1747.

11. The Construction (General Provisions) Regulations5.1. 1961 No. 1580.

12. The Construction (Working Places) Regulations,5.1. 1966 No. 94.

13. The Electricity (Factories Act) Special Regulations,1908 and 1944. S.R. & 0.1908, No.1312, as amendedby S.R. & O. 1944 No. 739.

14. The Factories Act (Northern Ireland) 1965.

15. The Shipbuilding and Ship Repairing Regulations(Northern Ireland) 1960.

16. The Construction (Lifting Operations) Regulations(Northern Ireland) 1963.

17. Wireless Telegraphy Act, 1949.

18. Certificate of exemption No. CON(LO)/1981/1'Rack and Pinion hoists'.

19. Hand 5 E Guidance Note PM 24 'Safety at rack andpinion hoists'.

20. Hand 5 E Guidance Note No. PM 27 'Constructionhoists'.

Copies of these documents may be obtained from:

H.M. Stationery Office49 High HolbornLondonWC1V 6 HB

*en*

Appendix B. Text deleted

BS 4465 : 1989Appendices A, C and D

Appendix C. Derivation of design windpressures

The design wind pressures in table 4 were prepared inaccordance with CP 3: Chapter V: Part 2.The following values were used:

(a) Basic wind speed:

All zones:Zone 1:Zone 2:Zone 3:Zone 4:

v = 20 m/sV = 38 m/s

\

V = 48 m/sV = 52 m/sV = 56 m/s

In service.

Out ofservice.

NOTE. The geographical locations of the above zones areillustrated in as 7212.

(b) Topography factor S 1 = 1

(c) Ground roughness, building size and height aboveground, factor S2 :

Height above ground

Om to 30 m S2 = 1.01Over 30 m to 60 m S2 = 1.1

Over 60mt090m S2 = 1.145

Over 90 m to 120 m S2 = 1.18

Over 120 m to 150 m S2 = 1.205

Over 150 m to 200 m S2 = 1.24(d) Statistical factor S3 =0.90 for a period of exposureof 13 years, using a probability level of 0.63.(e) Design wind pressure q =kV.2

where k = 0.613 and

V. =V X SI X S2 X S3Example:

V. = 38 x 1 x 1.01 x 0.90 = 34.54q = 0.613 X (34.54)2 = 731 N/m2

Appendix D. The use of steels of highertensile strength than those of steelscomplying with BS 4360The use of suitable steels with higher tensile strengths thanthose covered by BS 4360 is permissible, provided thatworking stresses are rigorously analysed having regard toloading conditions, and the design of the structure isverified by adequate testing.The working stresses thus derived should not exceed thepermissible stresses calculated in accordance with 6.1.

In all cases for steels having a yield stress greater than 82 %of the ultimate stress the basic stresses

Pat,ba.' Pac,ba. forfir .. so, Pbt.bas, Pbc,bas and PqC,ba.shou Id be takenrespectively as the basic stresses for steel of grade 55

49

BS 4465 : 1989Append ix E

complying with BS 4360 in accordance with 6.1, increasedin the ratio

Ys + Us

Ys,55 + UI.55

where

UI.55 and Y..55 are the minimum ultimate tensilestrength and the yield stress of grade 55 steel complyingwith BS 4360;

UI and YI are the minimum ultimate tensile strengthand the yield stress for the steel under consideration.

Extreme care has to be taken in the use of these steelswhere the design criteria are crippling, buckling, or lateralinstability, in applications where the increased deflectionsresulting from higher stresses may give rise to criticalconditions. In all cases it is essential to ensure that anysteel used has adequate properties in respect of impact atlow temperature, weldability and fatigue.

Appendix E. Basic formula for calculationof C s (see 6.1.4.2.3.3)

The critical compression stress C. (in N/mm2 ) for sectionssymmetrical about the x-x axis may be calculated from

C. = 21 j{£I~GK

~+ ::;)}

where

Zx is the gross section modulus about x-x axis;I is the effective length of compression flange;

Ix - IvJJ.=~;

x

Ix is the moment of inertia of the whole sectionabout x-x axis;

Iv is the moment of inertia of the whole sectionabout y-y axis;

£ is Young's modulus (= 205000 N/mm2);G is the modulus of rigidity (taken as 0.4£);K is the appropriate torsion constant;

EIh 2w is the warping constant (= =-- for I sections);

2

he is the distance between flange centroids;If is the moment of inertia of the compression flange

only about y-y axis of the girder.(a) For I sections. The above formula reduces to

C =410000 j{IvK ( Ifhe2

)}· Zxl JJ.1 + 12.3

Kf

For sections composed of approximately rectangularelements,

K ~ ~ (b~3 )where

band tare breadth'and average thickness of eachelement.

(b) For channel and Z sections. The formula in (a) abovegives conservative values.(c) For box members. Conservative values of C. are

obtained by substituting in the formula in (a) above,

4A.2K~

~(Slt)

where

A. is the total enclosed area of section;S is the length of each element of the periphery;t is the thickness of each element (in the case of

curtailed flanges, the effective thickness);e.g. for a box of depth d, width b, and uniform thickness t,

2b2 d2 tK~-

d+b(d) For a plate or flat in bending in a plane parallel to itssurface. Substituting appropriate values of K, etc.,

fC =410000-

· lDwhere

t is the thickness;

D is the depth;I is the effective length of part in compression.

Appendix F. Text deleted

50

CERTIFICATE OF TYPE TEST FOR BUilDERS' HOIST SAFETY GEAR

Name and address of maker

Date of test:

I 1

Safety gear model no.:

I I

Model no. of hoist upon

I I

Rated load of that hoist:

I I

which test was conducted: kg

No. of repeated tests:

I I

Design tripping speed

]m/s

I

Design life, Ld (years):

I I

Average number of expected

I I

Design stopping distance:

I I

operations, Nom

Actual stopping

I mmax.1Index of protection code: liPI

distances:

Other models of hoist upon which I Modelno. I I I Ithis safety gear may be used:I Rated load I kg I kg I kg I kg

Declaration

I/We certify that onI 19

I the equipment was tested and found to be satisfactory,and that the foregoing is a correct report of the result.

Signature(s) :I I I

I

Qualifications: II I

I

Address(es):

Date:I 19 I

If employed by a company or association give name and address:

I

iiiii!!!!!!iiiiiiiiii

iiiii!!!!!!

*UJ

*

BS4465 : 1989Appendix G

Appendix G. Certificate of type test for safety gear

A typical type test certificate for safety gear is as follows (see 31.2.6).

51

as 4465 1989

Index

Accessibility 3.2Aerodynamic slenderness Figure 2Alarm, emergency 10.5Angle of fleet 13.2.2

Bearings, drive machinery 15.11Bolts 7.2

black 7.2.1.3friction grip 7.2.1.1precision 7.2.1.2

Bolting, basic stressesin bearing 7.2.1.2.5in fatigue 9.7in shear 7.2.1.2.3in tension 7.2.1.2.2in tension and shear 7.2.1.2.4

Brake 15.1; 15.2; 16emergency release 16.7production test 31.4.4shaft fixing 15.10

Buffers 20

Cabinets, electrical 26.7control 29.2

access to 29.2.3notice 29.2.4location of 29.2.2

heating of 26.7Cables, electrical 26

flexible 26.5trailing 26.5; 26.6

Cage 10construction 10.1.1doors 10.2.2; 10.2.4; 10.2.5emergency roof opening 10.4

switch 22.7floor 10.1.4gates 10.2.2; 10.2.4; 10.2.5load distribution 10.1.2; 10.1.3manual controls 29.4.2; 29.4.3overrun 21

Clearancescage/landing 10.3enclosure/structure 10.2.5

Connections, structuralbasic stresses 7

bolts 7.2rivets 7.2.2studs 7.2welds 7.1

fatigue stressesbolts 9.7rivets 9.7welds 9.8

Control equipment, etc. 29circuits 29.1; 29.3.4circuit protection 29.1.5; 29.3.7; 29.3.8contactors 29.3failsafe 29.1.3; 29.1.4manual 29.4non-conductive 29.5relays 29.3supply 29.1.2time lag 29.1.1voltage 29.1.2

Counterweights 17overru n 17.6

Diagrams, electrical 26.8instruction manual 32

Doors, cage 10.2.2; 10.2.4; 10.2.5Drawings, electrical 26.8Driving machinery 15

bearings 15.11belts 15.6brake 15.1; 15.2; 16

emergency release 16.7production test 31.4.4shaft fixing 15.10

chains and chainwheels 15.6component alignment 15.12drive 15.3gearing 15.7lubrication 15.11shaft fixing 15.10stresses 15.8

Drum, winding 13.2diameter 13.2.1; 19.3grooves 13.2.3.1; 13.2.3.2shaft fixing 15.10

Duty factor 5.3

Earth bonding 28production check 31.4.5

Effective length (structure) 8.1Effective width (structural panels) 8.2Electrical

cabinets 26.7cables 26.1; 26.2; 26.3; 26.5drawings and diagrams 26.8earth bonding 28insulation resistance test 31.4.4.2terminals 26.4wiring 26

Electrical protection 26.2brake 16.6external influences 27

Electrical safety switches and contactssee Safety switches

Emergencyaudible alarm 10.5brake release 16.7egress from cage 10.4

Enclosurecage 10.2hoistway 11

External influences, protection 27

Fail safecontrol circuit 29.1.3; 29.1.4non.conductive control 29.5

Fatigue stresses 9Fluctuating loads 9Force coefficients 3.1.6.5Friction grip bolts 7.2.1

Gatescage 10.2.2; 10.2.5hoistway 11interlocking 12.1

non-conductive control 29.5.2production test 31.4.3

locking devices 12.2Gearing

drive machinery 15.7shaft fixing 15.10

Governorsafety gear 18tripping speeds 19

52

Guarding 23construction of 23.2driving machinery 15.5rack and pinion 14.5

Guides 9.9Guide rails 9.9

Hoistway 11enclosure 11gates 11

Impact factor 4.1.1; 4.1.2In service wind

loads 4.1.1pressures 4.1.4.3

Instruction manual 32Insulation resistance test 31.4.4.2Interference suppression 30Interlocking of gates 12

non-conductive control 29.5.2production tests 31.4.3

Isolating switch 25

Legislation Appendix ALoad

combinations 4.1distribution in cage 10.1.2; 10.1.3spectrum factor 4.1.1; 4.1.3

Loads 4.1due to climate and natural

phenomena 4.2Locking devices, gate 12.2Lubrication of bearings 15.11

Manual controls 29.4cage 29.4.2cage roof 29.4.3; 29.4.4marking 29.4.7operators key 29.4.6remote 29.4.5

Manual, instruction 32Marking and notices 24

control gear cabinet 29.2.4counterweight 17.7governor 19.2manual controls 29.4.7safety gear 18.2

Notices see marking

Out-of-servicewind load 4.1.1wind pressure 4.1.4.3

Overruncage 21counterweight 21

Overspeed governor 18; 19testing 31.4.3

Overspill switch 22.6

Pinion, driving 14.2Precision bolts 7.2.1.2Production tests 31.4

electrical 31.4.4functional 31.4.2safety devices 31.4.3

Proof test, prototype 31.3Proportions of structural members 8

Pulleys 13.2diameter 13.2.1; 19.3governor rope 18.9grooves 13.2.3.1; 13.2.3.3shaft fixing 15.10

Rack and pinion suspension 14drive pinion 14.2engagement 14.4guarding 14.5rack 14.3

Rated load 2.7;4.1.1Reliability 3.1Remote control 29.4.5Rivets

basic stresses 7.2.2fatigue stresses 9.7

Robertsons factor Table 8Rope suspension 13Ropes

diameter 13.1.2; 19.3reverse bends 13.1.5; 19.3speeds 13.1.4terminations 13.1.6; 19.3wire 13.1working load 13.1.3

iiiii~

Safety gear 18type test 31.2type test certificate Appendix Gproduction test 31.4.2

Safety switches and contacts 22cage roof door 22.7gate locks 12.2.4; 12.2.5; 12.2.7overspill 22.6production tests 31.4.3safety gear 18.6slack rope 22.5terminal slowing 22.4terminal stopping 22.2ultimate limit 21.2; 21.3; 22.3

*(J)

*

Section ratio Figure 2Sheaves, traction 13.2

diameter 13.2.1grooves 13.2.4shaft fixing 15.10

Shielding factors 4.1.4.6Slack rope switch 22.5Slenderness ratio 6.1.3Solidity ratio Figure 2Spacing ratio Figure 2Steel selection 5.1Stresses

basic 6.1.1basic, inconnections 7bearing 6.1.6bending 6.1.4bolting 7.2.1combined 6.1.7compressive 6.1.3driving machinerY 15.8fatigue 9permissible working 5.3rivets 7.2.2secondary 6.3shear 6.1.5tensile 6.1.2transverse bending 6.1.8yield, design verification 6.2

Suppression, radio and TV interferenceSuspension

rope 13rack and pinion 14

Terminal slowing switchesTerminal stopping switches

production test 31.4.3Terminals, electrical 26.4

22.422.2

53

as 4465 : 1989

Testing 31production 31.4

electrical 31.4.4functional 31.4.2safety devices 31.4.3

prototype proof 31.3safety gear type 31.2

Traction sheaves 13.2diameter 13.2.1grooves 13.2.4shaft fixing 15.10

Tripping speeds, governor 19Type test, safety gear 31.2

Ultimate limit switch 21.2; 21.3production test 31.4.3

Vision panel in doors 10.2.4Voltage, control 29.1.2

30

Web plates 8.3Web stiffeners 8.3Welded connections and stresses 7.1

butt, general 7.1.2butt, partial penetration 7.1.3fatigue 9.8fillet 7.1.4

Windaction 4.1.4.1loads 4.1.4

calculations 4.1.4.4In-service 4.1.1out-of-service 4.1.1

pressure 4.1.4.2derivation of Appendix C

Wire ropes 13.1diameter 13.1.2; 19.3reverse bends 13.1.5; 19.3speeds 13.1.4termination 13.1.6; 19.3working load 13.1.3

Wiring, electrical 26

54 blank

iiiiii!!!!!!iiiiiiiiiiii-iiiiii!!!!!!

*(/)

*

55 blank

56 blank

iiii~iiiiiiii-iiii~

*(J)

*

Publications referred to

as 22a Specificationforshortpitchtransmissionprecisionrollerchainsand chainwheelsas 302 Wire ropesforcranes,excavatorsand generalengineeringpurposesas 329 Steelwire ropesforelectricliftsas 436 Spur and helicalgears

Part 2 aasic rack form, modules and accuracy (1 to 50 metric module)

Part 3 Method of calculation of contact and root bending stresslimitations for metallic involute gears

The use of structural steel in building

Part 2 Metric units

Specification for bevel gears (machine cut)

Covered electrodes for the manual metal-arc welding of carbon and carbon manganese steels

Methods of destructive testing fusion welded joints and weld metal in steel

Specification for worm gearing

Part 1 Inch un its

Part 2 Metric units

Specification for radio Interference limitsand measurements for household appliances, portable tools and other

electricalequipment causing similar types of interference

Rules for the design of cranes

*Part 1 Specification for classification,stresscalculations and design criteriafor structures

The design and testing of steeloverhead runway beams

Specification for endless wedge belt drives and endless V-belt drives

Specification for weldable structural steels

High strength frictiongrip bolts and associated nuts and washers for structural engineering

Part 1 General grade

Part 2 Higher grade bolts,and nuts and general grade washers

Part 3 Higher grade bolts (waisted shank), nuts and general grade washers

The use of high strength frictiongrip bolts in structural steelwork. Metric series

Part 1 General grade

Part 2 Higher grade (parallelshank)

Part 3 Higher grade (waisted shank)

Specification for the process of arc welding of carbon and carbon manganese steels

Code of practice for safety of machinery

Specification for factory-built assemblies of switchgear and controlgear for voltages upto and including 1000 V a.c.and

1200 V d.c.

Part 1 General requirements

Classificationof degrees of protection provided by enclosuresLifts and service lifts

* Part 1 Safety rules for the construction and installationof electriclifts

Code of prectice for the safe use of construction hoists

Code of basic data for the design of buildings

Chapter V. Loading

Part 2 Wind loads

tEN 109 Safety rules for the construction and installation of builders hoists -Category I

Institution of Electrical Engineers Regulations for electrical installations

as 449

as 545as 639as 709as 721

as soo

as 2573

as 2853as 3790as 4360as 4395

as 4604

as 5135as 5304as 5486

as 5490as 5655

as 7212CP3

*Referred to in the foreword only.

t Draft European standard in preparation.

This British Standard, having been prepared under the direction ofthe Mechanical Handling Standards Committee, was publishedunder the authority of the Board of BSI and comes into effect on31 January 1990@ British Standards Institution, 1989

First published May 1969Second edition October 1986Third edition January 1990

ISBN 0580 17857 9

The following BSI references relate to the work on this standard:Committee reference MHE/6Drafts for comment 83/79025 DC and 88/77702 DC

British Standards Institution. Incorporated by Royal Charter, BSI isthe independent national body for the preparation of BritishStandards. It is the UK member of the International Organizationfor Standardization and UK sponsor of the British NationalCommittee of the International Electrotechnical Commission.

In addition to the preparation and promulgation of standards, BSIoffers specialist services including the provision of informationthrough the BSI Library and Standardline Database; Technical Helpto Exporters; and other services. Advice can be obtained from theEnquiry Section, BSI, Milton Keynes MK14 6lE, telephone0908 221166, telex 825777.Copyright. Users of British Standards are reminded that copyrightsubsists in all BSI publications. No part of this publication may be

BS 4465 1989

reproduced in any form without the prior permission in writing ofBS!. This does not preclude the free use, in the course ofimplementing the standard, of necessary details such as symbols andsize, type or grade designations. Enquiries should be addressed tothe Publications Manager, BSI, Linford Wood, Milton KeynesMK14 6LE. The number for telephone enquiries is 0908 220022and for telex 825777.

Contract requirements. A British Standard does not purport toinclude all the necessary provisions of a contract. Users of BritishStandards are responsible for their correct application.

Revision of British Standards. British Standards are revised, whennecessary, by the issue either of amendments or of revised editions.It is important that users of British Standards should ascertain thatthey are in possession of the latest amendments or editions.

Automatic updating service. BSI provides an economic, individualand automatic standards updating service called PLUS. Details areavailable from BSI Enquiry Section at Milton Keynes, telephone0908221166, telex 825777.

Information on all BSI publications is in the BSI Catalogue,supplemented each month by BSI News which is available tosubscribing members of BSI and gives details of new publications,revisions, amendments and withdrawn standards. Any person who,when making use of a British Standard, encounters an inaccuracy orambiguity, is requested to notify BSI without delay in order thatthe matter may be investigated and appropriate action taken.

Committees responsible for this British StandardThe preparation of this British Standard was entrusted by theMechanical Handling Standards Policy Committee (MHE/-) toTechnical Committee MHE/6 upon which the following bodieswere represented:

Associated Offices' Technical CommitteeBEAMA Ltd.Building Employers ConfederationConstruction Health and Safety GroupConstruction Plant-hire Association

Amendments issued since publication

Amd. No. Date of issue Text affected

Department of Trade and Industry, Mechanical and ElectricalEngineering Division

Federation of Civil Engineering ContractorsFederation of Manufacturers of Construction Equipment and CranesFederation of Master BuildersFederation of Wire Rope Manufacturers of Great BritainHealth and Safety ExecutiveIndependent Engineering Insurers' CommitteeInstitution of Mechanical Engineers

British Standards Institution. 2 Park Street London W1A 2BS . Telephone 01-629 9000 . Telex 266933

9001-9 MHE/6

Documents

BS 4465 (1989) Electric Hoists