OLEH: KELOMPOK ANGGOTA
: 28 : 1. Astrid Parama Ningrum (13 (13406026) 2. Bona Mangkirap (13406043) 3. Irma Sofiani (13406049) 4. Nadia Fadhilah Riza (13406069) 5. 5.Pri Prila laS Sist ista aLi Lilly llyJ Jan ane e(1 (134 34060 06080 80) ) 6. Ira Wulandari (13406094)
1. Participantsunderstandtheconstructionofalatheandhowtooperateit 2. Participantsunderstandtheprocessesofturning 3. Part Partici icipa pant nts s unde underst rstan and d the the para paramet meters ers of turn turnin ing g proc proces ess s and and how to determinethem.
Turningisamachiningprocessinwhichasinglepointtoolremovesmaterialfrom the the surf surfa ace of a rota rotati ting ng cyli cylind ndri rica cal l work workpi piec ece. e. The The tool tool is fed fed line linear arly ly in a directionparalleltotheaxisofrotation,asillustratedbelow.
Turningistraditionallycarriedoutonamachinetoolcalledlathe,whichprovides powe power r to turn turn the the part part at a given iven rota rotati tion onal al spe speed and and to feed feed the the tool tool at a specifiedrateanddepthofcut.
Principalcomponentsofanenginelathe:
contai containsthe nsthe driveunitto driveunitto rotatethespindle, rotatethespindle, whichrotat whichrotatesthe esthe
work
,oppositetheheadstockinwhichacenterismountedtosupport theotherendoftheworkpiece
iswherethecuttingtoolisheld is where here the the tool tool post post is fast fasten ene ed, desi desig gned ned to feed feed in a
directionperpendiculartothecarriagemovement
isdesignedtoslidealongthewaysofthelatheinordertofeed thetoolparalleltotheaxisofrotation
are like tracks tracks along along which which the carriag carriage e rides, rides, andthey aremade withgreatprecisiontoachieveahighdegreeofparallelismrelativetothe spindleaxis
ofthelathe providesarigidframeforthemachinetool drivesthecarriagerotatingattheproperspeedtoobtainthe desiredfeedrate
Equationforturningparameters: Cut rate
vc
Feed rate
v f
Depth Depthof ofcut cut
d
Cuttin Cuttingt gtime ime
t c
MaterialRemovalRate
where:
.d .N
1000
f .N
(d 0
d m )
2
d 0
lt v f
MRR
f . A.vc
d0=originaldiameterofthepart(mm) dm=finaldiameterofthepart(mm) f
= feedrate(mm/r)
lt=lengthofthecylindricalworkpart(mm) A
= Area of the workpart
N=rotationalspeed(rev/min) MRR=materialremovalrate(mm3/min) ttc=cuttingtime(s) vf=cuttingspeed(mm/rot)
Operationsrelatedtoturning:
The tool tool is fed radial radially ly into into the rotati rotatingwork ngwork on one end to create create a flat flat surfaceontheend
Instea Insteadof dof feeding feeding the tool tool paralle parallel ltotheaxisof totheaxisof rotati rotationof onof the work,the work,the toolisfedatanangle,thuscreatingataperedcylinderofconicalshape.
The The tool tool foll follow ows s a cont contou our r that that is othe other r than than stra straig ight, ht, thus thus crea creati ting ng a contouredformintheturnedpart
In this this operat operation ion, , someti sometimes mes called calledform forming ing, , the tool tool has a shape shape that that is impartedtotheworkbyplungingthetoolradicallyintothework
Thecuttingedgeofthetoolisusedtocutanangleonthecornerofthe cylinder,formingwhatiscalledachamfer
The tool tool is fed fed radia radially lly into into the the rotat rotatin ing g work work of some some locat location ion alon along g its its lengthtocutofftheendofthepart
A poin pointe ted d tool tool is fed fed linea linearly rly acro across ss the outs outsid ide e surfa surface ce of the the rota rotati ting ng workpartinadirectionparalleltotheaxisofrotationatalargeeffective feedratethuscreatingthreadsinthecylinder
A single single-p -poi oint nt tool tool is fed fed linea linearly rly, , para paralle llel l to the the axis axis of rota rotatio tion, n, on the the insidediameterofanexistingholeinthepart
Drilling Drilling can beperformed beperformed ona lathe lathe byfee by feedin ding g the drill drill into into the rotati rotating ng workalongitsaxis
Metalformingoperationusedtoproducearegularcross-hatchedpattern intheworksurface
Inourpracticum,wedidturningprocessandthereareprocessesthat wetry,suchasfacing,centreboring,diameterreducing,groovingand threading.
Wesetthelatheinzerocoordinatetoavoidbacklashthatwillaffectthe turningprocesses.
In facing facing process processes, es, the surfaceof surfaceof specime specimen n have a coarse. coarse. It might might becauseofthecuttingtoolhavedefect.
Cutt Cutter er whic which h used used for for faci facing ng, , cent centre re bori boring ng and and diam diamet eter er redu reduci cing ng processesisdifferentwithcutteringroovingandthreadingprocesses. Cutterthatpracticanusedbechangedtoavoiddamageoncutter.But itisbettertochangethecuttingtoolineveryprocess.
Incentreboringproce Incentreboringprocesseswemakethe sseswemakethespacefortheholde spacefortheholdertoreduce rtoreduce vibrationintheworkpiece
Turningprocesseswithlathedidnotusedbacklashcompensator,but we did did alte altern rna ative tive ways ays such such as turn turnin ing g the the hand and wheel heel unt unto the the oppositedirectiontwotimestoreducethegapbetweengears.
Thespeedofspindlemustbehighersolathecanmakebettersurface finishandtotreatthecuttertoolbetter.Becauseinlowrate,thespindle willdamagethecutter.
The The turn turnin ing g proc proces esses ses wil wil have have bad bad resu result lt if the the feed feed rate rate high higher er. . It meanstheworkiecemovefasterandwouldmakethesurfacenotflat
In turn turning ing proce processe sses s neede needed d the the conce concent ntra rati tion on of oper operat ator or to make make suretheresultisasitwants.Thedimensionofspecimenisdepending withtheoperator,soitisnotgoodtoproducing.
Inreducingdiameterthespecimenwillbecutoffiftheoperatorletthe lathekeeprunning.
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Whiledoingfacingprocess,thezeropositionofthecuttingtoolandcutting placementwillaffe placementwillaffectfacin ctfacingresult.abad gresult.abadfacingresult facingresulttwillhavescrap twillhavescraponit onit surfaceanditwillaffectoncentreboringandcentredrillingprocess.
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In the observa observatio tion n ,the ,the centre centre boring boring proces process s mean mean to give give place placefor for the nip nipper per so the the work work piece iece will ill have have no vib vibrati ration on cau caused sed by thre thread adin ing g processthatcanmaketheresultbad.Theotherreasonoftheflankingis toreducetheresultedmoment.
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The workpiec workpiece e must must not not be nip nip to long long from from the the spin spindl dle e becau because se it will will increasethemomentwhichmeanstheworkpiecewillbemoreunstable.
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Cutt Cutter er must must be chan changed ged in ever every y proce process ss becau because se each each proc proces ess s need need differentcutter.Ifawrongcutterusedinwrongprocessitwilldamagedthe cutter.
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Higherspindleratewillproducedabettersurfacefinishandlongercutter’s life.Becauselowspin life.Becauselowspindleratewill dleratewillmakegreat makegreaterimpactfor erimpactforthecutterwh thecutterwhich ich willdamagethecuttergreater.
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Higherfeedratewillmak Higherfeedratewillmaketheturnin etheturningresultworse gresultworse.Because .Becausewhichmeans whichmeans theworkpiecewillmovefastandmaybeskipthecut,sothesurfaceresult willnotflat.
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Abadresultinthreadingprocesshappen Abadresultinthread ingprocesshappenedintheobservation edintheobservation,itbecause ,itbecause when when loca locate te the the zero zero posit positio ion n for for thre thread ading ing proce process ss there there’s ’s an error error so depthofcutbecometodeepandthethreadi depthofcutbecometodeepandthethreadingresultbecome ngresultbecomeunarranged unarranged andfullofchipleft.Whileagood andfullofchipleft.Whileagoodonewillprovideabettersurf onewillprovideabettersurface(with ace(without out chip)withgoodthreadresult.
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In redu reduci cing ng diam diamet eter er proc proces ess, s, we cann cannot ot cut the the work work piec piece e too too deep deep becauseitwilldamagethecutter,soifyouwanttomakeadeepcut,you mustdotheprocessseveraltimesinsmalldepth.
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Backlashinturningprocesswillaffectthezeroposition.Toovercomethis prob proble lem, m, we must must loca locate te the the cutte cutter r agai again n afte after r turni turning ng the work work piec piece. e. About1to2timesrotation.
We did 5 proces processes ses in this this experim experiment, ent, there there are: are: Facing Facing, , center center boring boring, , reductiondiameter, reductiondiameter,groovingandthreading. groovingandthreading. Eachprocessneedsdiffere Eachprocessneedsdifferent nt types types of cutting cutting tools. tools. A wrong wrong placeme placement nt of cuttin cutting g tool tool may defect defect the produc product t anddamaged anddamaged the cutter cutter also. also. In each each process process, , we also also need need to determinethezeropositionofcuttingtoolinadditiontoproducedagood qualityproduct.
Infacingprocess, Infacingprocess,afaultindetermini afaultindeterminingzeropositi ngzeropositionwillresult onwillresultascrapon ascrapon thesurfaceofworkpiece thesurfaceofworkpiecetherefore thereforewillaffected willaffectedthecenterborin thecenterboringprocess. gprocess. Thecentreboringprocessmeanstogivethenipperplace,sothatthework piecewoul piecewouldnot dnot bentandrebound bentandrebound.We .We setthe setthe work workpie pieceandflanke ceandflankedit. dit. Sothattheworkpiecewouldhavenovibrationandmomentforcecaused by thread threading ing process process which which can make the bad result. result. A long long proces process s of threadingprocesswillturntoacuttingprocess.
The The work piece shou should ld place not to far from rom the nip nipper, per, in orde rder to decreasethemomentforcesothatitwillstable
High Higher er spind spindle le rate rate will will prod produc uced ed a bett better er (smoo (smooth th) ) surfa surface ce resul result t and and longercutter’slife.Because thelowspindleratewillmakeabiggerimpact tothecutteranditwilldamagethecutter
High Higher er feed feed rate rate woul would d make make the the surfa surface ce of work work piec piece e wors worse; e; it will will be roughandhavescraponit.Becauseifworkpiecemovefasteritprobably willskipthecut,sothatthesurfacewillnotsmooth
Inthisexperiment,thethread Inthisexperiment,thethreadingprocessappea ingprocessappearedtobefailed.Thereare redtobefailed.Thereare tworeasonstwoexplainedit.First,theageofcuttingtoolistooold,sothat italreadydull.Thisconditionresultabadeffectontheworkpiece,suchus roughandscraped.Thesecondoneisthehumanerror.Azeropositioning was un-loca un-located ted inthesameorder, sothere are two differ different ent threadpiled threadpiled up.
Inreducing Inreducing diamet diameterproces erprocess,deeperdepth s,deeperdepth cut will will damage damaged d the cuttin cutting g tool tool. . If we want ant to cre create ate a deep deep cut, cut, we have have to repe repeat at the the proc proce ess severaltimes
Inthisturningexper Inthisturningexperimen iment,we t,we did 5 process processes, es, whichare whichare facing facing,centreborin ,centreboring, g, diameterreduction,grooving,andthreading. Each Each turning turning process process needed needed differen different t types typesof of cuttin cutting g tools.For tools.For facing facing, , centre centre boring,anddiameterreductionprocessusedthesamecuttingtool.Forgrooving andthreadingprocesswerebothusingdifferenttypesofcuttingtool.Ifawrong cuttingtoolusedinthewrongprocess,itwoulddamagedthecuttingtool. First,wehavetodecidedthezeropositionofthecuttingtool,whichwouldeffect thesurfaceoftheworkpiece.Afalsezeropositionwouldeffecttheresultof facingprocess,evenmore,thecentreboringprocess. Thecentreboringprocessmeantogivetheholderplace,sothattheworkpiece wouldnotbentandrebound.Iftheworkpiecenotbeenholded,workpiecewould have have endu endura ranc nce e limi limit t caus cause e of the the dyna dynami mic c forc force e from from the the cutt cuttin ing g tool tool.. The The workp workpie iece ce might might not not hold holded ed to far far in the the hold holder er, , which which means means the work work piec piece e locatedfarfromthespindlethatwouldincreasemomentforcetotheworkpiece. Inthreadingprocess Inthreadingprocess,ifwedidtheprocessatalongtime ,ifwedidtheprocessatalongtime,theproces ,theprocesswouldturn swouldturn outtobeacut-offprocess. Thechipswereformedinseveralways.Incentreboring,facinganddiameter reductionprocessthechipswerecontinuousandshort.Thiswascausedby relativelysmallfeedsanddepths.Inthreadingprocess,thechipswere segmented(causedbythecutingtool’sdamagededge)andlong(causedby smallfeedandsmalldepth). High Higher er spind spindle le rate rate would would produ produce ce a smoo smooth ther er surf surface ace workp workpie iece ce and long longer er cuttingtool’slife.Alowspindleratewouldmakeagreaterimpactforthecutting tool tool which which woul would d make make a grea greate ter r damag damage e to the the cutt cuttin ing g tool. tool. Highe Higher r feed feed rate rate wouldmakethesurfaceofworkpiecerougher. Thereisasmallboxattachedtotheleadscrewthatcontainsafewgearsthatcan beusedtocontroltheleadscrewforthreadingproce beusedtocontrolthelead screwforthreadingprocess.Eachgeariscompatible ss.Eachgeariscompatible forafewnumberoffeeds.Theadjustmentsontheusedgearshouldmatchwith
whatweadjustedpreviouslyonthefeed.Ifitisdifferent,itcouldcausedefects onthethread. A bad bad resu result lt in threa threadi ding ng proce process ss happe happened ned in this this exper experim imen ent. t. It happe happene ned d beca becaus use e when when the the oper operat ator or loca locate ted d the the zero zero posi positi tion on for for thre thread adin ing g proc proces ess s ther there’ e’s s an erro error r occu occurr rre ed, so depth epth of cut cut beco become me too too deep deep, , the the thre thread adin ing g processresultbecom processresultbecomeunarranged eunarranged,andthesurface ,andthesurfaceofworkpiece ofworkpiecewascoveredof wascoveredof chips. A broke roken n cutting tools wou would make the chips covered red the surface of the workpiece. The The used used turn turnin ing g maci macine ne did did not not use use a back backla lash sh comp compen ensa sato tor. r. Back Backla lash sh in turn turnin ing g proc proces ess s will will effe effect ct in deci decidi din ng the the zero zero posit ositio ion n. To overc vercom ome e this this problem,wemustalwayslocatedthecuttingtoolaftertheturningprocesswork on the the workp workpie iece ce. . But But there there isa way to comp compro romi mise se the the backl backlas ash h withou without t any any additionalcomponentattchedtotheturning.Thatisbyturningthehandwheelto theoppositedirectiontwotimesinordertoreducethegapbetweengears.
1. Withahighcuttingspeed,wecouldgetsmoothturningresult.Ifthecutting spee speed d is lowe lower r than than the the feed feed, , thre thread ad coul could d be form formed ed on the work workpi piece ece surface. 2. Intheturningproces Intheturningprocess,thereisaplanepar s,thereisaplaneparticular ticularlydesigned lydesignedfortheflowof fortheflowof the chipsso chipsso they theywil will lflo flowout wout themsel themselves ves. .Bec Because ause ifthechips stay,the stay,the frictionthatoccurscouldresistthefeedandwearoutthecuttingtool. 3. Inthreadingprocess,thedepthofcutcouldnotbetoodeepinaturning proc proces ess s beca ecause use it coul could d wear wear out and and even ven brea break k the the cutt cuttin ing g too tool. Therefore,tomakeadeepcutthread,theprocessshouldbedoneinmany times. 4. Each turning proc rocess has has different types of cutting ing tools needed. Ther Theref efor ore, e, the the cutt cuttin ing g tool tool shou should ld be repl replac aced ed with with the the prop proper er one one for for everyturningprocess.
5. From From the the obser bserva vati tio on we coul could d see see the the back backla lash sh that that occu occurs rs on the the workta worktablewherea blewhereas s we rotate rotate the spindle spindle that moves moves theworktable theworktable once once and and twice twice, , the the tabl table e has has not not moved moved yet. yet. To over overcom come e this this proble problem, m, we shouldrotatethespindletwomorethantherotationneeded. 6. Theresultoftheturningprocessmightnotbeappropriatetoourrequired dime dimens nsio ion. n. It coul could d be caus caused ed by the the sett settin ing g of 0 posi positi tion on befo before re the the processwasnotveryprecise.
We do the the obse observ rvat atio ions ns of turn turnin ing g proc proces ess s in thre three e base base proc proces ess s which which are are facing,diameterreductionandthreading. First,wedothefacingprocesstocreateaflatsurfaceontheend.Thenwedothe reductionofthediameter.Inthiscasethediameterthatwereducedistheinside diameter.Finally,weobservethemakingofthreading. Thethreadingprocesseshaveseveralsteps.Wecannotdothethreadingdirectly intothedepthwewantbecaus intothedepthwewantbecauseitcandamagethe eitcandamagethecuttingtools cuttingtools.Wealsohaveto .Wealsohaveto becarefulwithexchangeeverycuttingtoolswhenwedothedifferentprocess,it isalsocanbethecauseofdamagingcuttingtools.(Ithappenedontheprevious observations.) The The chip chips s were were forme formed d in many many ways. ways. In cent centre re borin boring, g, facin facing g and diam diamet eter er redu reduct ction ion proc proces ess s the chip chips s were were contin continuou uous s and short. short. This This was was cause caused d by relat lative ively small feeds and dep depths. In threa reading ing proce roces ss, the chips ips were segm segmen ented ted (caus (caused ed by the the cuti cuting ng tool’ tool’s s damag damaged ed edge) edge) and long long (cause (caused d by smallfeedandsmalldepth) Higher Higher spindle spindle rate rate will will produce produced da a better better surface surface finishandlongercutter’slife, becauselowspindleratewillmakegreaterimpactforthecuttingtoolswhichwill damagetheformoftheworkpiece.Higherfeedratewillmaketheturningresult worse.Itcanhappenbecausetheworkpiecewillmovefastandmaybeskipthe cut,sothesurfaceresultwillnotflat.
Back Backla lash sh in turn turnin ing g proc proces ess s will will aff affect ect the the zero zero posi positi tion on. . To over overco come me this this problem,wemustlocatethecutteragainafterturningtheworkpiece.About1to 2timesrotation.Abadresultinthreadingprocesshappenedinthisexperiment.It happe happene ned d becau because se when when the opera operato tor r locat located ed the the zero zero posit positio ion n for for threa threadi ding ng process there’ re’s an error ror occurred red, so depth of cut become too deep eep, the threadingprocessresultbecomeunarranged,andthesurfaceofworkpiecewas coveredofchips. The The used used lath lathe e didn didn’t ’t use use a back backla lash sh com compensa ensattor. But But there is a way way to compromisethebacklashwitho compromisethebacklashwithoutanyadditionalcompon utanyadditionalcomponentattche entattchedto dtothelathe. thelathe. Thatis Thatis byturningthe byturningthe handwhe handwheelto elto theopposite theopposite direct direction ion two timesin timesin order orderto to reducethegapbetweengears. Thereisasmallboxattachedtotheleadscrewthatcontainsafewgearsthatcan beusedtocontroltheleadscrewforthreadingproce beusedtocontrolthelead screwforthreadingprocess.Eachgeariscompatible ss.Eachgeariscompatible forafewnumberoffeeds.Theadjustmentsontheusedgearshouldmatchwith whatweadjustedpreviouslyonthefeed.Ifitisdifferent,itcouldcausedefects onthethread
1.
Principalcomponentsofanenginelatheis: contai contains nsthe the drive drive unit unit to rotate rotate the spindle spindle, , which whichrot rotate ates s
thework , oppo opposi site te the the head headst stoc ock k in whic which h a cent center er is moun mounte ted d to
supporttheotherendoftheworkpiece iswherethecuttingtoolisheld
is wher where e the the tool tool post post is fast fasten ened ed, , desig designe ned d to feed feed in a
directionperpendiculartothecarriagemovement is desig designe ned d to slide slide along along the the ways ways of the lathe lathe in orde order r to
feedthetoolparalleltotheaxisofrotation areliketracksalongwhichthecarriagerides,andtheyaremade
withgreatprecisiontoachieveahighdegreeofparallelismrelativeto thespindleaxis ofthelathe providesarigidframeforthemachinetool
drives drives the carriage carriage rotati rotating ng at the proper proper speed speed to obtain obtain
thedesiredfeedrate
2.
Turn Turnin ing g is a mach machin inin ing g proc proces ess s in whic which h a sing single le poin point t tool tool remo remove ves s materialfromthesurfaceofarotatingcylindricalworkpiece
3.
Processesofturning: a. Facingprocess b. Diameterreductionprocess c. Threadingprocess d. Taperturning e. Contourturning f.
Formturning
g. Cut-off h. Drilling
i.
Boring
j.
Knurling
k. Chamfering
4. The The shap shape e of the the cutt cuttin ing g tool tool used used and and the the dire direct ctio ion n of the the feed feed vary vary betweenprocesses
5. Parametersofturningprocess: a.
Cutting Speed, it’sconnectedwithrotationalspeedandtheaverage diameterofworkpiece.
b. b.
Dept Depthof hofcut cutcan canbede bedefin finedb edbyad yadju just sting ingthe thepos positi ition onofcut ofcutti ting ngtoo tool l usin using g the the spind spindle le. . Dept Depth h of cut cut affe affects cts the the fina final l dime dimens nsio ion n of the the work work piece.In piece.In reducin reducing g diamet diameter erproc process ess, ,dep depth th ofcut affect affects s the finaldimensionofworkpiece.However,infacingprocessdepthof cutaffectsthethicknessofmaterialremoval.
c. c.
Fee Feed, can can be defi define ne by the the sele select ctor or leve lever. r. The The dire direct ctio ion n of Feed Feed affectsthefinaldimensionofworkpiece.Ifthepurposeofturningis fed the circumf circumfere erence nce of work work piece’s piece’s surf surfac ace, e, then then the the dire direct ctio ion n wouldbeaxial.Intheotherhand,ifthepurposeofturningprocess isfedtheedgeoftheworkpiece,thenthedirectionwouldberadial.
d.
Leng engthofcu thofcutis tis thesi thesize ze of thewo thework rk pie piece that thathas has bee beendon ndoneby turningprocess.Itisaffectedbyfeedrateandtimeofcutting. Thoseparameters,determinetheresultofturningprocess.
1.
Describeandsketchtheprocedureofturningprocessesthathasbeendone duringtheobservation: a. Facingprocess
Set Set the the cutt cutting ing tool tool in a right right posit positio ion. n. Set Set it in the the tool toolsp spot ot. . In ordertoputthecuttingtoolonthecentreofworkpiece.
Adjustthepositionofthecuttingtoolsinonelinewithlongitudeof theenginelathe.Then,rotatethecuttingtoolsto45degrees.
Set Set the the dept depth h of cut cut by sett settin ing g the the dista distanc nce e of cutt cuttin ing g tool tool and and workpiece.Thiscanbedonebysettingthetoolpost.
Setthedirectionoffeedandthefeedrate.
Turningprocess.
facingprocess
b. Diameterreductionprocess
At At first first, , one one edge edge of the the work work piec piece e is drille drilled d with with a cent center er drill drill attachedonthetailstock
Thecuttingtoolispositionedat90cuttingangle Adjus Adjust t the direct direction ion and the feed feed rate (v f )byadjustingthefeed rateselectorleverasrequired.
Adjustingthedepthofcut(a):byadjustingthepositionofcutting toolwiththespindle.
Turningprocess
Diameterreductionprocess
Diameterreductionresult
Threadingprocess
Atfirst,doesthegroovingprocess,whichismakingaclearfinal, mark mark for the thread threadingprocess ingprocess. . The groovin grooving g process process uses uses the groo groovi ving ng tool tool. . The The dept depth h of groo groovi ving ng is equa equal l to the the dept depth h of threadthatisgoingtobedone.
Settingtherequiredpitch:thesizeofpitchissetbythegearbox accordingtothespecificationsneeded.
Settingofthreadingdial:bycheckingtheleadscrewnipper,the gear inside should match the specification stated on the threadingprocesstable.
Turningprocess
grooving
2.
threading process
Writethenameandfunctionoftheenginelathecomponentsthatwereused duringtheobservation! contai containsthe nsthe driveunitto driveunitto rotatethespindle rotatethespindle, ,whi whichrotat chrotatesthe esthe
work ,oppositetheheadstockinwhichacenterismountedtosupport
theotherendoftheworkpiece iswherethecuttingtoolisheld
is where here the the too tool post post is fast faste ened ned, desi design gned ed to feed feed in a
directionperpendiculartothecarriagemovement isdesignedtoslidealongthewaysofthelatheinordertofeed
thetoolparalleltotheaxisofrotation are like tracks tracks along along which which the carriage carriage rides, rides, andthey are made made
withgreatprecisiontoachieveahighdegreeofparallelismrelativetothe spindleaxis ofthelathe providesarigidframeforthemachinetool
drivesthecarriagerotatingattheproperspeedtoobtainthe
desiredfeedrate
Drawtheshapeofcuttingtoolsandshowthevarietiesoftheiranglesand planes!
ALandARtypeforboring,chamferingandturningprocessesthatallow90 angle.
BLand BRtypefor turning turning, , boringdan boringdan chamfer chamfering ing, , suitab suitablefor lefor roughing. roughing. Havetheleadangleof15.
Type C has a square end, common monly used sed for turning, boring and chamfering.
Type D has 800 angle and an angle tool for undercutting O.D/I.D chamfering
Typ Type E is a sta standa ndard cutt cuttin ing g too tool with with 60 that is usually lly used sed for Vgrooving,chamfering,boring,turning,andfacing
ELandERtypehave60 0angletooffsetapartthatisdifficulttoreach.Also suitableforV-grooving.
FL and and FR type type, , comm common only ly used used for for lathe lathe turr turret et for for stra stradd ddle le facin facing, g, but but couldalsobeusedforconventionallathe
GLandGRtypeforfacingthatisclosetochuckjaws
TSAtypeforboringwithboringbarangleof900
TSCtypeforboringwithboringbarangleof30
4.
CTLandCTRusedforcut-offforsmalldiameter,alsoforgrooving
0
0
TSEtypeforboringwithboringangleof45
Dete Determ rmin ine e the cutt cuttin ing g speed speed, , spin spindle dle rota rotatio tiona nal l speed, speed, depth depth of cut, cut, and feedratethatareneededtodothediameterreductionandtheHSStypeof cuttingtoolandhowtosetthearrangementoffeedlever? Leverarrangementsetting:
Drillaholeforclampingwithdrillchuck-centerdrill
Set the clamp clamp so the workpi workpiece ece stays stays rigidly rigidlyin in its place place during during turnin turning g process.
Set Set the the 0 posi positi tion on, , acco accord rdin ing g to the the dist distan ance ce of cutt cuttin ing g edge edge and and the the surfaceofworkpiece.
Determineandsetthedepthofcut,spindlerotationalspeed,andfeedin themachinetoourrequirement:
In orde order r to arra arrange nge the the spind spindle le rota rotati tion onal al speed speed, , the the leve lever r is turne turned d to lett letter er B, and and the the othe other r leve lever r is turn turned ed to 3 to get get the the 370 370 mm/r mm/rad adia ian n spindlerotationalspeed.
Tosetthefeed direct direction, ion, pullor pullor pushthelever. pushthelever. Pullthelevertoreduce Pullthelevertoreduce the the work workpi piec ece e surf surfac ace. e. We need need to dete determ rmin ine e the the feed feed rate rate requ requir ired ed
befo before re settin setting g the the feed feed rate rate of the the cuttin cutting g tool tool. . Then Then, , set set the the leve lever. r. To createacertainspeedforfeedrate,inthiscase0,05mm/radwhereitis shownAS8Xinthetableontheheadstock.SetthefirstlevertoletterA, thesecondleverto8,andthethirdlevertoX.
5.
Write3effectscausedbyadjustingcuttingtoolhigherthantheaxisofwork piece! a.
Frictionwilloccurbetweenthechinpartofthecuttingtoolandthe workpiece,whichcouldmakethefinishedworkpieceverythin.
b.
The The surf surfac ace e of the the work work piec piece e woul would d be text textur ured ed (not (not flat flat). ). The The dime dimens nsio ion n of the the fini finish shed ed prod produc uct t migh might t not not appr approp opri riat ate e to our our requirement.Itiscommonlyfoundinthefacingprocess.
c.
The fractu fracturechips rechips ofthecuttingtool ofthecuttingtool orthework piececouldjump piececouldjump outofthechuck.Ifthecuttingtoolisnotplacedintherightposition, itcouldeasily itcouldeasily wear out. Ithastosupply moreenergybeca moreenergybecausethe usethe cutt cutting ing edge edge is not not right rightly ly consu consumed med when when cont contac acted ted to the the work work piece.
6.
Describethefactorsinitiatingthecostofturningprocess! a.
Cutting Speed , it’ it’s con connected with rot rotational speed eed and and the averagediameterofworkpiece.
b. b.
Dept Depthof hofcut cut,can ,canbede bedefin fineby ebyadj adjus usti ting ngthe thepos posit itio ionof nofcut cuttin tingto gtool ol usingthespindle.Depthofcutaffectsthefinaldimensionofthewor piece. piece. In reducin reducing g diamet diameter er process process, , depth depth of cut affect affects s the final final dimens dimension ion of work work piece. piece. Howeve However, r, in facing facing proces process s depth depth of cut affectsthethicknessofmaterialremoval.
c.
Fee Feed, canbe canbe defi defin neby thesel theselec ecto torle rleve ver. r. Thedi Thedire rect ctio ionof nof Feed Feed affectsthefinaldimensionofworkpiece.Ifthepurposeofturningis fed fed the the circu circumf mfer eren ence ce of work work piece’s piece’s surfac surface, e, then then the directio direction n wouldbeaxial.Intheotherhand,ifthepurposeofturningprocess isfedtheedgeoftheworkpiece,thenthedirectionwouldberadial.
d.
Leng engthofcu thofcutis tis thesi thesize ze of thewo thework rk piece iece tha thathasbe thasbee endone ndone by turningprocess.Itisaffectedbyfeedrateandtimeofcutting
e. e.
The Thema mach chin ine ean and dit its sma main inta tain inan ance ce Amachine Amachine witha witha certain certain typeof typeof qualitywill qualitywill havea havea certai certaintypeof ntypeof perf perfom oman ance ce. . This This will will effe effect ct the the effi effice cenc ncy y of elec electr trici icity ty. . A good good machinewillnotwastetoomuchelectrcity.
f.
Set-up Set-up Set-up process process will effect effect the quality quality of the produc products. ts. If there there is a mistakeinthesetting-upprocess,thentherewillbeapossibiltythat theproductproducedwillhavedefects
7.
Explainandmentionthefunctionofknurlingprocess,grooving,andform turning! a.
Knur Knurlin ling g is a turn turnin ing g proc proces ess s that that will will prod produc uce e a cubic cubic patt patter ern n or stripepatternonthesurfacebyusingknurlingtool.Knurlingisalso known as metal working process that is used f or regular crosshatchedpatternontheworkpiecesurface.
b.
Groovingisaprocessthatissimilartodiameterreductionprocess on the edge edge of thread threading ing workpie workpiece. ce. This proces process s is done done before before
threadinginordertomaketheendofthread.Groovingcanbedone inthreeshapes,whicharesquare,round,andV-shaped.
c.
FormTurningisturningprocessthatusesacuttingtooltoreduce thediameteroftheworkpieceandalsotoformtheworkpieceasthe contourofthecuttingtool.Formturningneedsspecialtemplatesto formtheworkpiece.
“Diktat kuliah proses manufaktur”, Operasi Pemesinan dan Mesin Perkakas.
Degarmo, E.Paul. ”Material And Processes in Manufacturing”,chapter 18.Shaping and Planning.
Groover, Mikell P. “Fundamentals of Modern Manufacturing”. John Wiley&Sons, 2002
.
Rochim,Taufiq. ”Teori dan Teknologi Proses Pemesinan”, Bab 2 Klasifikasi dan Elemen Dasar Proses Pemesinan.
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