Alignment Test Report

8/9/2019 Alignment Test Report

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MANUFACTURING ENGINEERING, NITW 143511

NATIONAL INSTITUTE OF TECHNOLOGY

WARANGAL, TELANGANA-506004

A report

On

ALIGNMENT TESTSSubmitt ! "#

SHARATH CHAN$RA %ALLEROLL NO.143511

MANUFACTURING ENGINEERING

Submitt ! T&

$'( )EN*AIAH N

ASSISTANT %ROFESSOR

$E%ARTMENT OF MECHANICAL ENGINEERING

CONTENTS

1ALIGNMENT TESTS




1( I+t'&!u ti&+( T#. / & G &m t'i 2/

(1 /t' i t+ //( t+ //(3 . ' i/m, ui!i/t + +! &i+ i! +(4 '&t ti&+/(5 / u ' + //

3( I+/t'um +t/ ' ui' ! &' i +m +t t /t/4( A i +m +t t /t &+ t

2ALIGNMENT TESTS




Introduction :

The dimensions of a gauge i!s su"fa#e finish and geome!"$ a"e de%enden! u%on !he inhe"en!&ua'i!$ and a##u"a#$ of !he ma#hine !oo' fo" i!s manufa#!u"e. A'so in mass %"odu#!ion !he (a"ious#om%onen!s %"odu#ed mus! )e of su#h a##u"a#$ !ha! !he$ ma$ )e assem)'ed on a non*se'e#!i(e

)asis. The a##u"a!e %"odu#!ion of !he #om%onen! %a"!s de%ends u%on !he a##u"a#$ of !he ma#hine!oo's.The #on!inuous'$ in#"easing demand fo" high'$ a##u"a!e ma#hined #om%onen!s has 'ed !o#onside"a)'e "esea"#h !o+a"ds means )$ +hi#h !he geome!"i# a##u"a#$ of ma#hines ma$ )eim%"o(ed and main!ained. I! is (e"$ im%o"!an! !he"efo"e !ha! unde" s!a!i# #ondi!ions !hea'ignmen! a##u"a#$ of !he ma#hine !oo's is #he#,ed )$ some geome!"i# !es!s. The !es!s +hi#h#he#, !he a'ignmen! a##u"a#$ of !he (a"ious %a"!s of a ma#hine !oo' a"e #a''ed s!a!i# "es!s.

A ma#hine !oo' a! !he same !ime mus! )e a)'e !o dis%'a$ !he desi"ed )eha(iou" and#ha"a#!e"is!i#s unde" no"ma' o%e"a!ing #ondi!ions as o%e"a!o" is #on#e"ned +i!h !he a#!ua'+o",ing of ma#hine !oo'. The"efo"e some a'ignmen! !es!s a"e %e"fo"med unde" d$nami# 'oading#ondi!ions and !hese a"e "efe""ed !o as d$nami# !es!s. Thus i! is o)(ious !ha! !he sa!isfa#!o"$+o",ing of a ma#hine unde" s!a!i# 'oading on'$ is no! suffi#ien! )u! a##oun! shou'd )e !a,en of !he (i)"a!ion and def'e#!ion of (a"ious ma#hine %a"!s unde" a#!ua' d$nami# 'oading a'so. Ind$nami# !es!s !he (a"ious mem)e"s a"e a#!ua''$ 'oaded and a'ignmen! !es!s a"e #a""ied ou!. A'so(a"ious %a"!s a"e e-#i!ed a! +o",ing f"e&uen#$ and )eha(iou" of ma#hine o)se"(ed. In o!he" +o"ds i! #ou'd )e said !ha! ma#hine !oo's fo" !he +o",sho% mus! )e a)'e !o %"odu#e +o",*%ie#esof gi(en a##u"a#$ +i!hin %"es#"i)ed 'imi!s #onsis!en!'$ and +i!hou! "e&ui"ing a"!is!i# s,i'' on !he

%a"! of !he o%e"a!o" and !ha! !he &ua'i!$ of +o",%ie#es de%ends u%on

7i8 /!iffness and "igidi!$ of !he ma#hine !oo' and i!s #om%onen!s %a"!s.

7ii8 The a'ignmen! of (a"ious ma#hine %a"!s in "e'a!ion !o one ano!he". This is (e"$ im%o"!an! )e#ause !he geome!"$ of (a"ious sha%es is )ased on !he "e'a!i(e mo!ion )e!+een (a"ious ma#hine %a"!s and hen#e on a'ignmen! of (a"ious %a"!s.

7iii8 The &ua'i!$ and a##u"a#$ of !he #on!"o' de(i#es and !he d"i(ing me#hanism.

/!iffness and "igidi!$ a"e a ma!!e" fo" designe" and on#e !es!s on a %"o!o!$%e of a #e"!ain designha(e gi(en sa!isfa#!o"$ "esu'!s !he"e is no need !o !es! !he ma#hine of same design o(e" and o(e" again. The a##u"a#$ of manufa#!u"e !he %"e#ision of #on!"o' de(i#es and d"i(ing me#hanismssu#h as 'ead s#"e+ of 'a!he a'' shou'd ha(e "e'a!i(e a'ignmen! as a##u"a!e as %ossi)'e. This

3ALIGNMENT TESTS




de%ends u%on !he &ua'i!$ of manufa#!u"e and ma$ (a"$ f"om ma#hine !o ma#hine. The"efo"eea#h ma#hine is su)0e#!ed !o an a##e%!an#e !es! #on#e"ning i!ems ii2 and iii2.The a##u"a#$ of ma#hine !oo's +hi#h #u! me!a' )$ "emo(ing #hi%s o" s+a"fs2 is !es!ed )$ meansof geome!"i#a' #he#,s and %"a#!i#a' !es!s.Geome!"i#a' #he#,s in#'ude #he#,ing of dimensions of fo"ms and %osi!ions of #om%onen!s as+e'' as #he#,ing of !hei" dis%'a#emen! "e'a!i(e !o one ano!he". These #om%"ise a'' !he o%e"a!ions+hi#h affe#! !he #om%onen!s of !he ma#hine and #on#e"n on'$ si es fo"ms %osi!ions and "e'a!i(emo(emen!s +hi#h ma$ affe#! !he a##u"a#$ of !he ma#hine. I! ma$ )e a%%"e#ia!ed !ha! !hegeome!"i#a' defini!ions a"e a)s!"a#! and "e'a!e on'$ !o imagina"$ 'ines and su"fa#es. In %"a#!i#e!he"efo"e me!"o'ogi#a' defini!ions a"e fo''o+ed +hi#h a"e #on#"e!e and !a,e a##oun! of "ea' 'inesand su"fa#es a##essi)'e !o measu"emen!. Me!"o'ogi#a' defini!ions #o(e" in a sing'e "esu'! a''ma#"o and mi#"o*geome!"i#a' e""o"s and a''o+ a "esu'! !o )e "ea#hed #o(e"ing a'' #auses of e""o"s+i!hou! dis!inguishing !hem f"om one ano!he". "a#!i#a' !es!s in#'ude !he ma#hining of !es! %ie#esa%%"o%"ia!e !o !he fundamen!a' %u"%oses fo" +hi#h !he ma#hine has )een designed and ha(ing

%"ede!e"mined 'imi!s and !o'e"an#es.The "esu'!s of %"a#!i#a' !es!s and geome!"i#a' #he#,s ma$ )e#om%a"ed on'$ in so fa" as !hese !+o ,inds of !es!s ha(e !he same o)0e#!6 in #ase )o!h do no! gi(e!he same "esu'! !he "esu'!s o)!ained )$ #a""$ing ou! %"a#!i#a' !es!s a"e a##e%!ed as (a'id. In #ase+he"e i! is e-%ensi(e o" diffi#u'! !o #ondu#! )o!h !$%es of !es!s !he a##u"a#$ of a ma#hine ma$ )e#he#,ed on'$ )$ geome!"i#a' #he#,s o" on'$ )$ %"a#!i#a' !es!s.

4ALIGNMENT TESTS




3. MEASURING INSTRUMENTS USED FOR TESTING :

The accuracy of the machine tools employed should be higher than the accuracy of

the components that it produces. Similarly the quality of the measuring equipment used

for machine tool testing should be commensurate with the quality expected from such

testing. A few commonly used equipments are

• Dial Indicators

• Test mandrels

• Straight edges

• Spirit levels

Alignment Tests on athe

16.3.16.3.1.

Levellin o! t"e M#c"ine.7efo"e !he (a"ious !es!s on an$ ma#hine !oo' a"e #a""ied ou! i! is (e"$ essen!ia' !ha! i! shou'd )e

ins!a''ed in !"u'$ ho"i on!a' and (e"!i#a' %'anes. In ho"i on!a' %'ane )o!h 'ongi!udina' and

!"ans(e"se di"e#!ions a"e e&ua''$ im%o"!an!. If sa$ an$ 'ong 'a!he )ed is no! ins!a''ed !"u'$

ho"i on!a' !he )ed +i'' unde"go a def'e#!ion !he"e)$ %"odu#ing a sim%'e )end and undesi"a)'e

s!"esses +i'' )e in!"odu#ed. If !he )ed is no! ins!a''ed !"u'$ ho"i on!a' in !"ans(e"se di"e#!ion

!+is! +i'' )e in!"odu#ed. Thus !he mo(emen! of !he sadda' #an8! )e in a s!"aigh! 'ine and !"ue

geome!"i# #$'inde" #an8! )e gene"a!ed.

Fo" %"o%e" ins!a''a!ion and main!enan#e of i!s a##u"a#$ a s%e#ia' #on#"e!e founda!ion of

#onside"a)'e de%!h mus! )e %"e%a"ed. A'so !his mus! )e insu'a!ed f"om !he su""ounding f'oo" )$

in!"odu#ing some fo"m of dam%ing.

5ALIGNMENT TESTS




The 'e(e' of !he ma#hine )ed in 'ongi!udina' and !"ans(e"se di"e#!ions is gene"a''$ !es!ed )$ a

sensi!i(e s%i"i! 'e(e'. The sadd'e is ,e%! a%%"o-ima!e'$ in !he #en!"e of !he )ed su%%o"!

fee!. The s%i"i! 'e(e' is !hen %'a#ed a! a*a Fig. 19.12 !he ensu"e !he 'e(e' in !he 'ongi!udina'

di"e#!ion. I! is !hen !"a(e"sed a'ong !he 'eng!h of )ed and "eadings a! (a"ious %'a#es no!ed do+n.

Fo" !es! in !"ans(e"se di"e#!ion !he 'e(e' is %'a#ed on a )"idge %ie#e !o s%an !he f"on! and "ea" guide+a$s and !hen "eading is no!ed. I! is %"efe"a)'e !o !a,e !+o "eadings in 'on*

gi!udina' and !"ans(e"se di"e#!ions simu'!aneous'$ so !ha! !he effe#! of ad0us!men!s in one

di"e#!ion ma$ a'so )e o)se"(ed in !he o!he". The "eadings in !"ans(e"se di"e#!ion "e(ea' an$

Fi ( 16(1

!+is! o" +ind in !he )ed. I! ma$ )e no!ed !ha! !he !+o guide+a$s ma$ )e %e"fe#!'$ 'e(e''ed in

'ongi!udina' di"e#!ion )u! migh! no! )e %a"a''e' !o ea#h o!he". This is "e(ea'ed )$ !he !es! in

!"ans(e"se di"e#!ion.

The s!"aigh!ness of )ed in 'ongi!udina' di"e#!ion fo" !he 'ong )eds #an a'so )e de!e"mined )$

o!he" me!hods e.g. using s!"aigh! edges au!o#o''ima!o"s o" )$ !au! +i"e me!hod. 7u! !he !es! in

!"ans(e"se di"e#!ion #an )e #a""ied ou! on'$ )$ s%i"i! 'e(e'.

I! is desi"ed !ha! !he f"on! guide+a$ shou'd )e #on(e- on'$ as !he #u!!ing fo"#es and !he +eigh! of

#a""iage a#! do+n+a"d on i!. If !he f"on! guide+a$s a"e #on#a(e !hen !he effe#! +i'' )e#omu'a!i(e. The !enden#$ of !he #a""iage unde" #u!!ing fo"#es is !o 'if! u%+a"ds f"om !he "ea"

and !his is %"e(en!ed )$ a gi) %'a#ed unde"nea!h !he guide+a$s. :i!h !he "esu'! an u%+a"d fo"#e

a#!s on !he "ea" guide+a$s 6 +hi#h mus! !he"efo"e )e made #on#a(e.T"ans(e"se 'e(e' ma$ )e in

an$ di"e#!ion )u! no !+is! #an )e !o'e"a!ed. 16(3( (

True Runnin o! Loc#tin $%linder o! M#in S&indle.

ocating cylinder is provided to locate the chuc! or face plate. "owever locating surfacecan#t be threaded one as threads get worn out soon and thus introducing play in faceplate or chuc!. Thus locating surface is cylindrical and this must run truly$ for only thenthe face plate etc.% can run truly. The dial indicator is fixed to the carriage &or any other fixed member' and the feeler of the indicator touches the locating surface. The surface

6ALIGNMENT TESTS




is then rotated on its axis and indictor should not show any movement of needle.

Fi . 16.'16.3.3.

A(i#l Sli& o! M#in S&indle #nd True Runnin o! S"oulder F#ce o! S&indle No)e.

et us first distinguish between the axial play and the axial slip. Axial play means theindispensable freedom of spindle movement in axial direction to prevent it fromsei(ing by heating. The spindle is supported between two bearings. Due to running of spindle% there will be a rise in temperature and thermal expansion of spindle would bethere. If no axial play is allowed% it would try to bend. Thus there will be no adverseeffect of axial play if the direction of cutting forces remains same. If the direction of cutting force changes% there would be some error introduced due to movement of spindle axially in either direction. )nder such conditions% therefore% it is advisable to cut

threads in one direction only. Axial slip is defined as the axial spindle movement which

Fi . 16.3follows the same pattern and is due to the manufacturing error. Actually this test ismeant to chec! this error. To test this the feeler of the dial gauge rests on the face of the

7ALIGNMENT TESTS




locating spindle shoulder and the dial gauge holder is clamped to the bed &*ig. +,.-'.The locating cylinder is then rotated and the change in reading noted down. Thereadings are ta!en at two diametrically opposite points. The total error indicated by themovement of the pointer includes three main sources of errors.

*i+ Axial slip due to error in bearings supporting the locating shoulder% i.e.% the bearingsare not perpendicular to the axis of rotation and due to it a point on the shoulder willmove axially in and out at diametrically opposite points.

*ii+ *ace of the locating shoulder not in a plane perpendicular to axis of rotation. &"i'Irregularities of front face.Due to axial slip% in screw cutting% the pitch will not be uniformdue to periodic movement of the spindle. This% however% is not important whileturning. 16.3.,.

True Runnin o! -e#d)toc $entre.

"eadstoc! centre is live centre and the wor!piece has to rotate with this centre. If it isnot true with the axis of movement of the spindle% eccentricity will be caused whileturning a wor!% as the ob axis would not coincide with the axis of rotation of mainspindle. *or testing this error% the feeler of the dial indicator is pressed perpendicular tothe taper surface of the centre &*ig. +,./'% and the spindle is rotated. The deviationindicated by the dial gauge gives the trueness of the centre.

16.3./.

0#r#lleli) o! t"e M#in S&indle to S#ddle Move ent.This has to be chec!ed in both vertical and hori(ontal planes. In this we require the useof mandrel. An important precaution in the use of mandrels and dial indicator ismentioned here. The mandrel must be so proportioned that its overhang does notproduce appreciable sag% or else the sag must be calculated and accounted for. The

8ALIGNMENT TESTS




rigidity indicator set up is also very important and must be carefully watched. 0therwisevariations in readings are recorded by pointer may be solely due to deflection of theindicator mounting in different positions and it becomes very difficult to detect andisolate the spurious deflection from the true variations.

If axis of the spindle is not parallel to bed in hori(ontal direction% a tapered surface isproduced.

Any deviation from parallelism of spindle axis from bed in vertical axis will produce ahyperboloid surface. *or this test% a mandrel is fitted in the taper soc!et of the spindle.1andrel has a concentric taper shan! which is close fit to the spindle nose taper. Thefeeler of the dial indicator is pressed on the mandrel and the carriage is moved. Theindication in hori(ontal plane is given by dial &b' and in vertical plane by dial &a' &*ig.+,.2'. In vertical plane the mandrel should be rising towards

Fi . 16./

the free end in order to counteract the weight of mandrel and ob. 3ut for counter4actingcutting forces% it should be lower towards free end. In hori(ontal plane% mandrel shouldbe inclined in a direction opposite to the direction of tool pressure.16.3.6.

True runnin o! t#&er )oc et in #in )&indle.

If the axis of tapered hole of the soc!et is not concentric with the main spindle axis%eccentric and tapered obs will be produced. To test it% a mandrel is fitted into thetapered hole and readings at two extremes of the mandrel are ta!en by means of a dialindicator as shown in *ie. +,.,.

Fi . 16.616.3.2.

0#r#lleli) o! t#il)toc uide #%) it" t"e ove ent o! c#rri# e.

9ALIGNMENT TESTS




Sometimes the ob is held between head4stoc! and tail stoc! centre for turning. In thatcase the ob axis must coincide with the tailstoc! centre. If the tailstoc! guideways arenot parallel with the carriage movement there will be some offset of the tailstoc! centreand this results in taper turning.

To chec! the parallelism of tailstoc! mideways in both the planes i.e.% hori(ontal andvertical% a bloc! is placed on the guideways as shown in *ig. +,.5 and the feeler of theindicator is touched on the hori(ontal and vertical surfaces of the bloc!. The dialindicator is held in the carriage and carriage is moved. Any error is indicted by thepointer of dial indicator.16.3.4.

Move ent o! u&&er )lide &#r#llel it" #in )&indle in vertic#l&l#ne.The dial indicator if fixed in the tool post. A mandrel is fitted in the spindle. The feeler

Fi . 16.2of the dial gauge is pressed against the mandrel in vertical plane and the upper slide ismoved longitudinally. This error is not tested in hori(ontal plane because there isswivelling arrangement for taper turning.

6arallelism of tailstoc! sleeve to saddle movement. If the tailstoc! sleeve is not parallelto the saddle movement% the height of dead centre would vary as varying lengths of sleeve are ta!en out. *or the obs held between two centres% it is necessary that thecentral axis of the dead centre be coaxial with the ob axis in both the planes. If it is not

so% the obmay be tilted up or down or in sideways due to the support of the dead centre. The testis carried out by fixing the dial indicator on the tool post and pressing the plunger against the sleeves first in vertical and then in hori(ontal plane &*ig. +,.7'. The carriageis moved along the full length of the sleeve and deviations as indicated by dial indicator are noted down. Tailstoc! sleeve should be rising towards the free end in vertical plane

10ALIGNMENT TESTS




and should be inclined towards the tool pressure in hori(ontal plane.16.3.15.

6arallelism of tailstoc! sleeve taper soc!et to saddle movement .

A mandrel is put in the sleeve soc!et. The dial gauge is fixed on the tool post andplunger is pressed against the mandreland saddle is moved from one side to the other.This test is carried out in both the hori(ontal and vertical planes. 16.3.11.

Ali n ent o! ot" t"e centre) in vertic#l &l#ne.3esides testing the parallelism of the axes individually &main spindle axis and tailstoc!axis' it is4necessary to chec! the relative position of the axes also. 3oth the axes maybe parallel to carriage movement but they may not be coinciding. So when a ob

Fi .16.15

is fitted between the centres% the axis of the ob will not be parallel to the carriagemovement. This test is to be carried out in vertical plane only. A mandrel is fittedbetween the two centres and dial gauge on the carriage. The feeler of the dial gauge ispressed against the mandrel in vertical plane as

Fi .16.11

11ALIGNMENT TESTS




Alignment Tests on 6illar Type Drilling 1achine &1etrology'7e!ore c#rr%in out t"e #li n ent te)t)8 t"e #c"ine i) &ro&erl% levelled in#ccord#nce

it" t"e #nu!#cturer9) in)truction). T"e v#riou) te)t) &er!or ed #re :

1. Fl#tne)) o! cl# &in )ur!#ce o! #)e. *Re!er Fi . 6.12+.

The test is performed by placing a straight edge on two gauge bloc!s on the base platein various positions and the error is noted down by inserting the feeler gauges. Thiserror should not exceed 8.+9+888 mm clamping surface and the surface should be

concave only.'. Fl#tne)) o! cl# &in )ur!#ce o! t# le.

This test is performed in the same manner as test &+'% but on the table. The permissibleerror is also same.

3. 0er&endicul#rit% o! drill "e#d uide to t"e #)e &l#te.

The squareness &perpendicularity' of drill head guide to the base plate is tested :*#+ in a vertical plane passing through the axes of both spindle and column% and* + in a plane at 78 to the plane at &a'.

The test is performed by placing the frame level &with graduations from 8.8- to 8.82mm9m' on guide

Fi . 16.12. $"ec in !l#tne)) o! cl# &in )ur!#ce o! #)e.column and base plate and the error is noted by noting the difference between the

12ALIGNMENT TESTS




readings of the two levels. This error should not exceed 8.;29+888 mm guide column for &a' and the guide column should be inclined at the upper end towards the front only% and8.+29+888 mm for &b'.

&6lease note that *ig. +,.+< shows the similar test for the squareness of drill head guidewith table% the only difference being that the frame level is to be placed on the baseinstead of table'.

,. 0er&endicul#rit% o! drill "e#d uide it" t# le.

This test is performed exactly in the same way as &b'. &=efer *ig. +,.+<' and the

permissible error is also same./. 0er&endicul#rit% o! )&indle )leeve it" #)e &l#te.

This test is performed in both the planes specified in test &-' and in the similar manner with the difference that the frame levels are to be placed on spindle sleeve and baseplate. The error &i.e.% the difference between the readings of the two levels' should notexceed 8.;29+888 mm for plane &a' and the sleeve should be inclined toward columnonly $ and 8.+29+888 mm for plane &b'.

6. True runnin o! )&indle t#&er.

*or this test% the test mandrel is placed in the tapered hole of spindle and a dial indicator is fixed on the table and its feeler made to scan the mandrel. The spindle is rotatedslowly and readings of indicator noted down. The error should not exceed 8.8-9+88 mmfor machines with taper upto 1orse >o. ; and 8.8/9-88 mm for machines with taper larger than 1orse >o. ;.

2. 0#r#lleli) o! t"e )&indle #(i) it" it) vertic#l ove ent.

This test is performed into two planes ?A' and &3 at right angles to each other. The testmandrel is fitted in the tapered hole of the spindle and the dial indicator is fixed on the

table with its feeler touching the mandrel. The spindle is ad usted in the middle positionof its travel. The readings of the dial indicator are noted when thespindle is moved in upper and lower directions of the middle position with slow verticalfeed mechanism.

13ALIGNMENT TESTS




Fi . 16.14. Te)t !or &er&endicul#rit% o! drill "e#d it" t# le.

Fi . 16.1

14ALIGNMENT TESTS




Fi . 16.'5For #c"ine) it" t#&er u&to Mor)e No. '.For #c"ine) it" t#&er l#r er t"#n Mor)e No. '.

*Lo er end o! #ndrel c#n e inclined to #rd) colu n onl%+.

4. S;u#rene)) o! cl# &in )ur!#ce o! t# le to it) #(i).

*or performing this test% the dial indicator is mounted in the tapered hole of the spindleand its feeler is made to touch the surface of table &=efer *ig. +,.;+'. Table is slowlyrotated and the readings of dial gauge noted down% which should not exceed 8.829-88mm diameter.

15ALIGNMENT TESTS




. S;u#rene)) o! )&indle #(i) it" t# le.

*or this test a straight edge is placed in positions AA# and 33#. @or! table is arranged inthe middle position of its vertical travel. The dial indicator is mounted in the spindletapered hole and its feeler made to touch the straight edge first say at A and readingnoted down. The spindle is rotated by +<8 so that the feeler touches at point A# andagain reading is noted down. The difference of two readings gives the error insquareness of spindle axis with table. Similar readings are noted down by placing thestraight edge in position 33#.

T"e &er i))i le error) #re 5.54<355 it" lo er end o! )&indle inclininto #rd) colu n onl% !or )et u& AA9 #nd 5.5/<355 !or )et u& 779.

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Alignment Test Report