Is 5749 - 1970 Specification for Ramshorn Hooks

8/13/2019 Is 5749 - 1970 Specification for Ramshorn Hooks

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information for citizens to secure access to information under the control of public authorities,in order to promote transparency and accountability in the working of every public authority,and whereas the attached publication of the Bureau of Indian Standards is of particular interestto the public, particularly disadvantaged communities and those engaged in the pursuit ofeducation and knowledge, the attached public safety standard is made available to promote thetimely dissemination of this information in an accurate manner to the public.

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IS : 5749 - 1970

( Reaffirmed 2008 )

Indian StandardSPECIFICATION FOR

FORGED RAMSHORN HOOKS( First Reprint JUNE 1989 )

UDC 6 2 1 . 8 6 . 0 6 1 . 1 : 6 2 1 . 8 8 5 . 2

Copyright 1971

B U R E A U O F I N D I A N S T A N D A R D SMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MAHG

NEW DELHI 11 00 02

Gr 3 January 1971


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AMENDMENT NO. 1 DECEMBER 1978

TO

IS : 5749 - 1970 SPECIFICATION FORFORGED RAMSHORN HOOKS

Corrigendum

(Page 4 , c lau se 4 . 1 , l i n e 4) Su bs t i tu te'0 .02 pe rce nt ' .for '0 .2 0 pe rc en t ' .

(MCPD)

Reprography Unit, BIS, New Delhi, India


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IS : 5749 - 1970

Indian Standard

SPECIFICATION FORFORGED RAMSHORN HOOKS

Lifting Chains and Associated Fittings and Components Sectional

Chairman

DR K . N . S INHA

Members

S H R I B L C H I T L A N G I A

Committee, EDC 49

Representing

Cen t ra l Min ing Resea rch S ta t ion (CSIR) , Dhanbad

Ind ian Cham Manufac tu r ing Co , Ca lcu t t aSH RI G. S . AGA RWA L ( Alternate )

DEPU T Y DI RECTO R ( MET- I I )

A S S I S T A N T D I R E C T O R ( W E L D IN G )( Alternate )

Research, Designs and Standards Organizat ion( Minis t ry of Rai lways ) , Chi t ta ranj an

DE PU TY DI RE CT OR , ST AN DA RD S Research , Des igns and Standards Organiza t ion( L O C O ) ( Mini stry of Railw ays ), Luc kno w

A S S I S TA N T D I R E C T O R ( W E L D -ING ) ( Alternate )

S H R I K G A N A PAT T YS H R I G C . J A I NSHRI K H K A L E

Jossop & Co Ltd, CalcuttaHindustan Steel LtdW H Brady & Co Lt d, Bo mba y

SHR I C K . RAD HA K R I S H NAN ( Alternate )SHRI P. S KA PO OR

S H R I L. F L A C K ( Alternate)

S H R I S. K A S T R U R I

Indi an Min ing Associa t ion, Calcu t ta

Min i s t ry o f Sh ipp ing & Trans por t (T ran sp or tWi n g )SHRI S RAGHAVAN ( Alternate )

S H R I K U L D I P C H A N D

SH RI C S R AO ( Alternate)MAJ T. V M A L I

Dir ecto rate Gene ral of Supplie s & Disposals NewDelhi

Ministry of Defence ( DGI )S HR I P. K K NA IR ( Alternate )

S H R I P R A J A G O P A L M E N O NS H R I P. M N I T YA N A N D A N

SH RI P K . NEV AT IASH RI V A OZ A

Gears Ind ia , Madras( Alternate )

Indian Link Chain Manufacturers Ltd , BombayAshok Steel Chain Manufactur ing Co, Bombay

SHR I F M F E RNA N DI Z ( Alternate )S H R I S . G . P R A D H A NS H R I B J R A M R A K H I A N I

Tak Machinery Ltd , BombayDirectorate General of Factory Advice Service and

Labour Ins t i tu tes ( Minis t ry of Labou r, E mplo y-ment & R ehabi l i ta t i on ) , Bomba y

SH RI H. N. JA GT IA NI ( Alternate)

( Continued on page 2 )

B U R E A U O F I N D I A N S T A N D A R D SMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002


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IS : 5749 - 1970

( Continued from page 1 )

MembersS HR I H A R A M S D A I E

RepresentingGeo Miller & Co Private Ltd, Calcutta

SHRI P. C H A T T E R J E E (Alternate)

S H R I N P R O Y C H O W D H U R Y Min ing and Al l ied Machin ery Co rpo rat i on Ltd ,Durgapur

S H R I S. N B A N E R J E E (Alternate)S H R I K C S A D H U K H A N The Comm iss ion ers for the Port of Cal cut ta,

Ca lcu t t aSHRI B. R C H A T T E R J E E (Alternate)

S H R I M V PA I A N K A R ,

Director ( Mec h Engg )Director General , ISI ( Ex-officio Member )

Secretary

S H R I M G . K R I S H N A R A O

Deputy

H o o k s a n d

Convener

S H RI H N J A G T I A N I

Members

SHRI A BANERJEES H R I P R E M C H O N A ( Alternate )

SHRI S K BA SUSHRI I C S H A R M A (Alternate)

S H RI G V C H E L I A MSH RI B L ???

Dir ect or ( Me ch Eng g ), ISI

A n c i l l a r ie s S u b c o m m i t t e e , E D C 4 9 : 3

Directora te General of Factory Advice Service andLab our Ins t i tu tes ( Minis t ry of Labo ur, Emp loyment & Rehabilitation ), Bombay

India I orge & Drop Stamping s Ltd , Mad ras

Hin dus tan Steel 1 Ltd, Ra nc hi

Ministry of Ship pin g & Trans port ( Tra nsp ort Wi ng )Indian Chain Manufactur ing Co, Calcut ta

SHRI G S A G A RWA L ( Alternate )

SH RI A M COOPER DEPUTY DIRECTOR, STANDARDS

( L O C O )S HR I K K DEVS H R I T C G H O S A L

S H R I S P G H O S H (Alternate)S H R I B M I S R AS H RI K C S A D H I K H A N

Maz ago n Dock Ltd , Bomb ayResearch, Designs and Standards Organizat ion

( Ministry of Railwavs ), LucknowJessop & Co Ltd, CalcuttaTh e Indi an Sta ndar d Wagon Co Ltd, Calcut t a

Heavv Engineer ing Co rporat ion Ltd, RanchiThe Commissioners for the Port of Callcutta, Calcutta

SHRI B R. CHATTERJEE ( Alternate )

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IS : 5749 - 1970

Indian Standard

SPECIFICATION FORFORGED RAMSHORN HOOKS

0 . F O R E W O R D

0.1 This India n Sta nda rd was adopted by the India n Stand ards Institutionon 29 May 1970, after the draft finalized by the Lifting Chains andAssociated Fittings an d Co mpon ents Sectional C ommi ttee h ad beenapproved by the Mechanical Engineering Division Council.

0. 2 The ramshorn hooks covered by this standard are intended for craneloads abov e the range of point hooks and ' C ' hooks covered i n the earliersta nda rds. Th e use of ram shor n hooks an d tr iang ular lifting eyes for loadsof 40 tonne s an d over is rec omm en ded in IS : 31 77 -1 96 5* . The seramshorn hooks are designed for included sling angles of 90.

0. 3 Th e information to be supplied with enqu iry and or der is given inAppendix A.

0.4 Th e ram sho rn hooks must be truly ba la nc ed if they are to rot ate freely

und er load. To ensu re this, it is desirable to mo un t the thrust bea rin gon a spherical seating ( see Appendix B ).

0.5 The recommendations for the use of ramshorn hooks are given inAppendix D.

0.6 In the prep ara tio n of this sta nda rd, conside rable assistance has bee nderived from:

Ent wur f DI N 15402 Blatt 1 La stha ken fur Hebezeu ge : Dopp elha ken :Ro hl in ge . ( Load hooks for hoisting mac hi ne ry : Clov e hooks :Bl an ks ). 1960. Deuts cher Normena usschuss.

En tw urf DI N 15402 Blatt 2 Last haken fur Hebez eug e : Dop pel hake n :Fert igte ile. ( Lo ad hooks for hoisti ng ma ch in er y : Clove hooks:Finished parts ). 1960. Deut sche r Norme nauss chuss .

BS 3017 : 1958 M ild steel forged ram sho rn hooks. British Sta nd ar dsInstitution.

*Code of practice for design of overhead (ravelling cranes and gantry cranes other t hansteel work cranes.

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IS : 5749 - 1970

0.7 For the purpose of dec idi ng wheth er a partic ular requi remen t of thisstandard is complied with, the final value, observed or calculated, expressing the result of a test or anal ysis , shall be ro un de d off in acco rd an ce withIS : 2 - 1960*. Th e nu mb er of significant p lace s ret ain ed in the rou nd edoff val ue should be the same as that of t he specified va lue in thisstandard.

1. SCOPE

1.1 Thi s st an da rd c overs forged ra msh orn ho oks ha vi ng a ra nge of safeworking loads from 40 to 250 tonnes and designed for included angles

be tween 0 and 90.

2. TERMINOLOGY

2. 0 For the purpos e of this st an da rd , the following definiti ons shall apply.

2.1 Competent Person A person w ho is appro ved a nd dec lare d assuch or recognized by the relevant statutory authority.

2.2 Inspector The representative of the purchaser.

2.3 Process ing - A ny tre at me nt of the hook subse quent to forging, suchas heat treatment and polishing.

2.4 Pr oo f Loa d Th e load to which a ramshorn hook shall be subj ectedin the finished condition.

2.5 Rating Th e max im um safe working load whic h the ram sho rn hookshall withstand.

3. RATING

3.1 The ramshorn hooks shall be rated according to the safe working loadgiven in Table 1.

4. MATERIAL

4.1 T he steel used for the ma nu fa ct ur e of swivel ass emb ly shall be ma de by open hearth, el ec tr ic or by ot he r oxyge n- bl own proc es s, having a ten si lestrength of at least 42 kgf mm 2 , an d shall be fully killed. It shall co nta innot less than 0 20 percent of al umi niu m. Sul phu r an d phosp horus shallnot exceed 0.050 an d 0.045 percent respectively. Any type of steel whi chmeets these requirements and when suitably heat treated meets the specificrequi reme nts with regard to the me cha nic al properties may be used.Steel s con formin g to Gra de 2 of IS : 187 5-1966 or IS : 3261 - 1966 meetthese requirements and are considered suitable.

*Rules for rounding off numerical values ( revised )Specification for carbon steel billets, blooms and slabs for forgings ( revised ).Specification for carbon steel forgings for shipbuilding industry.

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IS : 5749 - 1970

5. FORM AND DIMENSIONS

5.1 T he form an d dimension s of ramsh orn hooks shall be in ac co rda ncewith Table 1.

5 .2 To le r ances on D imens ions Th e tolerances on dimens ions a 1 , a 2 ,b1 , b 2 , d 1 and h shall be in ac co rda nc e with Table 1. T h e forgeddime nsion s for wh ich no to ler anc e has bee n specified in the tab le shall benot less tha n the values given in th e tab le an d shall not excee d these bymore than +8 percent.

5.2.1 Mac hin ing tolerances shall be in acc ord an ce with m edi um classof IS : 2102-1969*.

5.3 Screw Threads Screw t hrea ds shall be eith er I SO metri c screwthreads conforming to IS 4218 - 1967 or round or knuckle threads.

T he length of the scre wed por tion shall be not less tha n the dim ension m. It the shank an d t he nut w hich secure it ar e drill ed for fixingof a r eta inin g pin , there shall rem ain a cont inuo us l engt h of sha nkenga ged by the nut on the load side at least eq ual to m.

6. WORKMANSHIP AND FINISH

6.1 Th e rai nsh orn hooks shall be free from d elec ts a nd sha ll be cle anlyforged in such a ma nn er that the macro sco pic flow line of the hooks follow

the body out lin e. All the surfaces shall be smoot hly finished.

6.1.1 Billets or bloom s to bo ma de into ra ms ho rn hooks shall be gr ad ua ll ya d uni form ly worked from ingots from whi ch at least five per cent of thetotal weight has been removed from the bottom end and 25 percent fromthe top end Whe n finished, the secti onal ar ea of the body as forgedshall not exceed one fourth of the mea n sectional ar ea of the origin al ingotused. Th e shank shall be wholly forged an d the re ma in de r wholly forgedan d mac hine d Mac hin e gas-cut ting ma y be used after rough forgingof shap e prov ide d an ad eq ua te excess of mat eri al is left for remo val ofsurface defects by machining.

7. HEAT TREATMENT

7.1 All the rams hor n hooks shall, before testing, be norma lize d by heat inguniformly in a furnac e until the whole of the mat eria l ha s attai ned atemperature between 880C and 910C. It shall then be withdrawn fromthe furnace and allowed to cool in still air.

*Allowable deviations for dimensions without specified tolerances ( first revision ).ISO metric screw threads ( issued in 6 parts ).

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T A B L E 1

R A T I N G

, P R O O F L O A D A N D D I M E N S I O N S F O R R A M S H O R N H O O K S

( C l a u s e s 3 . 1 , 5 1 , 5 2 , 8 . 1 a n d 1 0 . 1

)

A l l d i m e n s i o n s i n m i l l i m e t r e s .

R a t i n g W ,

t o n n e s

4 0

5 0

6 3

8 0

1 0 0

1 2 5

1 6 0

2 0 0

2 5 0

P r o o f l o a d P , t o n n e s

a 1 ( 2 8 , P )

a 2

( 0 . 6 a 1 )

7 0

8 5

1 0 0

1 2 0

1 4 5

1 7 0

2 1 5

2 6 6

3 3 3

1 2 5 4

1 4 0 4

1 6 0 5

1 8 0

5 2 0 0 6 2 2 4 7 2 5 0 8 2 8 0 9 3 1 5 1 0

1 0 0 3

1 1 2 3

1 2 5 4

1 4 0

4

1 6 0 5

1 8 0 5 2 0 0 6 2 2 4 7 2 5 0 8

IS : 5749 - 1970

6

N O T F U n

d e r c u t a c c o r d i n g t o I S . 1

3 6 9 - 1 9 6 1 ' D i m e n s i o n s o f s c r e w t h r e a d r u n o u t s a n d u n d e r c u t s ' .


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b 1 ( 0 8 5 a

1

)

b 2 ( 0 3 3 5 a 1 )

d 1 ( 0 8 5 a

1

)

d 2 ( 0 . 7

1 a 1 )

d 2 *

f ( 4 2 5 a l )

h ( 1 . 0 6 a 1 )

l 1 l 2 m , M i n

r 1 ( 0 . 1

2 5 a 1 )

r 2 ( 1 . 1

8 a 1

)

r 3 ( 1 . 1

8 a 1

)

1 0 6 + 1 1 0

4 3 + 5 0

1 0 6 5

9 0 M 9 0 6

5 3 0

1 3 2 + 1 3 0

1 8 8

5 1 0 8 0 1 6 1 3 1 5

0

1 1 8 + 1 2 0

4 6 + 5 0

1 1 8 6

1 0 0

M 1 0 0 6

6 0 0

1 5 0 + 1 5 0

2 0 7

5 7 2 9 0 1 8 1 4 1 7

0

1 3 2 + 1 4 0

5 3 + 6 0

1 3 2 7

1 1 0

M 1 1 0 6

6 7 0

1 7 0 + 1 7 0

2 3 4

6 4 5 1 0

0 2 0 1 6 1 9 0

1 5 0 +

6 0 +

1 5 0

1 2 5

M 1 2 5 6

7 5 0

1 9 0 +

2 6 0

7 0 5 1 1

2 2 2 1 8 2 1 2

1 6 0 6 0 8 1 9 0 1 7 0 + 1 8 0

6 7 + 7 0

1 7 0 9

1 4 0

M 1 4 0 6

8 5 0

2 1 2 + 2 1 0

2 8 2

7 9 0 1 2

5 2 5 2 0 2 3 6

1 9 0 + 2 0 2 1 2 + 2 2

0

0

7 5 + 8

8 5 + 9

0

0

1 9 0 1 0 2 1 2 1 1

1 6 0

1 8 0

M l 6 0 6 M 1 8 0 6

9 5 0

1 0 6 0

2 3 6 + 2 4 2 6 5 + 2 7

0

0

3 2 5

3 5 7

8 9 6

1 0 0 5

1 4 0

1 6 0

2 8

3 2

2 2

2 5

2 6 5

3 0 0

2 3 b + 2 5 0

9 5 + 1 0 0

2 3 6 1 2

2 0 0

M 2 0 0 6

1 1 8 0

3 0 0 + 3 0 0

4 0 5

1 1 3 0

1 8 0 3 6 2 8 3 3

5

2 6 5 +

1 0 6 +

2 8 0 1 1 0

2 6 5 1 3

2 2 5

M 2 2 5 6

1 3 2 0

3 3 5 + 3 4 0

4 5 5

1 2 6 0

2 0 0 4 0 3 2 3 7

5

IS : 5749 - 1970

~ J

* E q u i v a l e n t k n u c k l e o r r o u n d t h r e a d s a r e p e r m i s s i b l e .

A d i f f e r e n t l e n g t h m a y b e s p e c i f i e d s u b j e c t t o a g r e e m e n t b e t w e e n t h e s u p p l i e r a n d t h e p u r c h a s e r .


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IS : 5749 - 1970

8. PROOF LOADING

8.1 Eac h completed ramsh orn hook shall, afte r heat tre at me nt, besubjecte d to a vertical proof load specified in Tab le 1. If the ve rti cal pro ofload test is appl ied in ac co rd an ce w ith Fig 1A, an add it io na l test of halfthe proof load specified for the vertical loading shall be appliedhori zont ally as indi cat ed in Fig 1B Prior to the app lic ati on of prooflo ad ing , each hook shall be ar a centre pu nc h ma rk at position a fromwhi ch scribe d lines shall be tr am mel le d to posit ion b After rem ova l ofthe load, the hook shall be re-scribed with the trammel unaltered, and thedifference between the scribed lines shall be the amount of permanent set.The permanent set shall in no case exceed 0 25 percent of the distance ab.Th e ramshor n hook shall then be thoroug hly e xam ine d by a co mpet ent pe rson and shal l be accepted as compl ying wit h th is s tandard only iffound free from flaw or defect

9. INSPECTIO N, CERTIFICATE OF TEST AND EXA MINA TIO N

9.1 The representative of the purchaser shall have access to the works ofthe manufacturer at all reasonable times for the purpose of witnessing thespecified tests and inspecting the machine and methods of examination.

9.2 Th e man ufa ctu rer shall supply a certificate of test and exam inat ionin the form show n in App end ix C with e ver y supply of ra msh orn hooksThe certificate shall give the results of all tests made

9.3 For the purpose of this standard, test ceitilicate in Form V of theIndian Dock Labourers Regulation, 1948, is acceptable provided that it isend orse d in col 2 by the ma nuf ac tur er or supplier t hat the ram sho rn hookscomply in all respects with this standard and that it states the material ofwhi ch the rams horn hooks are ma de and the details of heat tre atm ent towhich they have been subjected

B

FIG 1 POSITIONS FOR LOAD TE S T


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IS : 5749 - 1970

10. MARKING

10.1 Each ramshorn hook shall, after testing, be permanently marked ona non-vital part with the following information:

a) Safe working load given in Table 1; b) Limiting included angles, that is 0 to 90; andc) Distinguishing marks or symbols as will allow identification with

the manufacturer's certificate of test and examination.10.1.1 Th e ramshorn hooks, may also be marked with the ISI

Certification Mark. NOTE The use of t he ISI Certi fication Mark is governed by the provisions of the

Indian S tandards Insti tution ( Certification Marks ) Act, and the Rules and Regulations made thereunder Presence of this mark on products covered by an IndianSta ndar d conveys the assurance that they have been produced to comply with the

requirement s of that standard, under a well-defined system of inspection, testing andquality control during production . This svstem, which is devised and supervised byISI and operated by the produce r, has the further safeguard that t he products asactually marketed are continuously checked by ISI for conformity to the standa rd.Details of condi tions , under which a licence for the use of the ISI Certification Markmay be grant ed to man ufa ctu res or processors, may be obtained from the India nStandards Institution

A P P E N D I X A(Clause 0.3)

INFORMATION TO BE SUPPLIED WITH ENQUIRY AND ORDER

The enquiry and order should state:a) safe working load,

b) form of screw thread,c) length of shank,d) method of manufacture, ande) further tests or chemical analysis required.

A P P E N D I X B(Clause 0.4)

THRUST BEARINGS FOR RAMSHORN HOOKS

B-1. Up to 125 tonnes capacity, standard single thrust ball bearings may be obtained. With the majority of ball thrust bearings, it is generallyfound necessary to locate the bearings on spigots or recesses on the hooknut and crosshead.

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IS : 5749 - 1970

B-2. For hooks above 125 tonnes capacity, tapered roller or specialthrust ball bearings are recommended. The bearing manufacturer should be consulted for suitable sizes.

B-3. When mounting single thrust ball bearings, care should be taken thatthe race does not take excessive horizontal load due to clearance betweenthe ramshorn hook shank and the bore of the crosshead.

A P P E N D I X C

(Clause 9.2)

FORM FOR CERTIFICATE OF TEST AND EXAMINATION

DISTINGUISHINGMARK

(1)

DESCRIPTIONOF RAMSHORN

HOOKS

(2)

MATERIAL

(3)

PROOF LOADAPPLIED

(4)tonnes

SAFE WORKINGLOAD

(5)

tonnes

Particulars of heat treatment to which the ramshorn hooks have been subjected areas follows:

We hereby certify that the ramshorn hooks, described above, complyin all respects with IS 5749-1970 'Specification for forged ramshorn hooks'and that they were subjected to the proof load and subsequently examinedand passed by a competent person.

Signature

Date

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IS : 5749 - 1970

A P P E N D I X D

(Clause 0.5)RECOMMENDATIONS FOR THE USE OF RAMSHORN HOOKS

D-1 . Th e ramsh orn hooks covered b y this sta nda rd should not be upg rad edfor use wi th slings at inc lude d angl es less th an 90, as the cap aci ty of thehook is also gove rned by the permi ssible stress in the sha nk. ( Ad va nt ag ecan not therefore be taken of the increased body streng th wh en the incl udedsling angles are less than 90. )

D-2. Ra ms ho rn hooks should not be used with sling legs at excessi veangl es, since the stress in the bod y of the hook will incre ase at a gre at errate than that in the sling leg. (T ab le s of ang ula r lo ading on slings will

not therefore be equally applicable to the loading on the ramshorn hooks. )D-3. For heavy an d bulk y loads, it is preferable to use a lifting be amsus pen ded from t he hook by tw o pairs of links at fixed ce nt re s, thecen tres of the link pins on the b eam b eing slightly grea ter th an the cen tre sof the bed di ame ter s of the hoo k.

D-4. An appr opri ate included angle betw een the link plat es would be ofthe orde r of 30. Wi th so small an inc lud ed ang le, the stress red uc ti onfactor for the hook body is less than one-half.

D-5 . To avoid the dan ger of overloa ding indivi dual link plates a nd theirassoc iate d link pins , due to th e possible tiltin g of th e be am an d thecons eque nt out-of-balance effect, link plate assembl ies should be desig nedwith an ample margin of safety.

D-6 . When using lifting beams, their length can be arranged to takevarying centres of slings to suit the loads an d ensure true bal anc ing. Tr ue

balancing is es se nt ia l in orde r that the hook may ro tate freely under loa dwhen required.

D-7. Wh en lifting bulky loads wher e the centr e of gravity is not cen tra l between the po in ts of sli ng ing , it is desi ra ble to ad ju st the leng th of theslings so tha t the cen tre of gravi ty of the load is i mme dia te ly below thecentre line of the hook.

D-8. In order to red uce t he effort requ ired to rota te the hook when lo ade d,it is recommended that the hook be carried on a ball or roller thrust

bearing ( see Appendix B ).

D-9 . Wh en sling angles app roach the limiting inc lude d angle for whichthe hook i s des ign ed, it is n ecessa ry to tak e ca re tha t nei the r of the tw ohorn s is s ubje cted to a load exce eding o ne-ha lf of the safe worki ng loadof the hook, since the stress red uct ion factor would the n be nearl y uni ty,an d any out-o f-bala nce effect could over load one of the horn s. Wh e nlifting loads just within the capa city of the hook, extre me care is neededin this respect.

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B U R E A U O F I N D I A N S T A N D A R D S

Headquarters:Manak Bhavan, 9 Bahadur Shah Zafar Marg, NEW DELHI 110002

Telephones: 331 01 31, 33 1 13 75 Telegrams: Manaksanstha( Common to all Offices )

Regional Offices: TelephoneCentral Manak Bhavan, 9 Bahadur Shah Zafar Marg,

NEW DELHI 110002*Eastern : 1 /14 C. I. T. Scheme VII M, V. I. P. Road,

Maniktola, CALCUTTA 700054 Northern : SCO 445-446, Sector 35 -C ,

CHANDIGARH 160036

Southern : C. I. T. Campus, MADRAS 600113

Western : Manakalaya, E9 MIDC, Marol, Andheri ( East),BOMBAY 400093

Branch Offices:'Pushpak', Nurmohamed Shaikh Marg, Khanpur,

AHMADABAD 380001Peenya Industrial Area 1st Stage , Bangalore Tumkur Road

BANGALORE 560058Gangotri Complex, 5th Floor, Bhadbhada Road, T. T. Nagar,

BHOPAL 462093Plot No. 82/83, Lewis Road, BHUBANESHWAR 75100253/5, Ward No 29, R.G. Barua Road, 5th Byelane,

GUWAHATI 7810035-8-56C L. N Gupta Marg ( Nampally Station Road ),HYDERABAD 500001

R14 Yudhister Marg, C Scheme, JAIPUR 302005

117/418 B Sarvodaya Nagar, KANPUR 208005

Patliputra Industrial Estate, PATNA 800013T.C. No. 14/1421, University P.O., Palayam

TRIVANDRUM 695035 Inspection Offices ( With Sale Point ):Pushpanjali, First Floor, 205-A West High Court Road,

Shankar Nagar Square, NAGPUR 440010Institution of Engineers ( India ) Building, 1332 Shivaji Nagar,PUNE 411005

* S a l e s Office in Calcutta is at 5 Chowri nghee Approach, P. O. Princep 27 68 00Street. Calcutta 700072

Salea Office in B ombay is at Novelt y Cha mbe rs, Gran t Road, 89 66 28Bombay 400007

Sales Office in Bangalore is at Unity Building, Narasimharaja Square, 22 36 71Bangalore 560002

Reprography Unit, BIS, New Delhi, India

331 01 31331 13 75

36 24 99

2 18 433 16 41

41 24 4241 25 19

.41 29 166 32 92 95

5 36 273 31 77

23 10 83

6 34 716 98 32

21 68 7621 82 92

6 23 056 21 046 21 17

2 51 712 51 71

5 24 35

2 63 482 63 49

38 49 5538 49 56

6 67 16

Documents

Is 5749 - 1970 Specification for Ramshorn Hooks