MA2004 help sheet - Summary Manufacturing Processes PDF

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Casting success : pouring rate, pouring temp, turbulence V 2 g h1 Continuity Law, A V A V 1 1 2 2 V Time need to fill mold cavity, T Cm:T of mf Q Flow velocity, metal, Rule, T ts V A n ( ) mold many small gas cavities at or slightly below the surface of casting. Penetration: When fluidity of liquid ...

Description

Cas t i ngs uc c es s:pour i ngr at e,pour i ngt emp,t ur bul ence

V 2=√ 2 g h 1 Cont i nui t yLaw, Q= A V = A V 1 1 2 2 V Ti meneedt ofi l lmol dc av i t y ,T Cm: T mf = Q Fl ow v el oci t y,

ofme t al ,

n

Chv o r i nov ’ sRul e,

T ts =C m

( VA )

mo l d

mat e r i al s,

( VA ) >( VA ) riser

Sandbl ow:Bal l oonshapedg asc avi t ycausedbyr el ease ofmol dgas esdur i ngpour i ng.Pi nhol es:For mat i onof man ysmal l gasc av i t i esa tors l i ght l ybel owt hes ur f ac eof r at i on:Wh enfl ui di t yofl i qui dmet al i shi gh, cas t i ng.Penet i tma ypenet r at ei nt osandmol dorc or e,c ausi ngc ast i ng s ur f ac et oc ons i stofami x t ur eofs andgr ai ns&met al . Mol ds hi f t :causedbysi dewi ser el at i v edi s pl acementof cope&dr ag.Mol dc r ack: Occ ur swhenc r ackdev el opsi n mol d,whi chl i qui dmet al c ans eept of or m a“ fi n”ont he finalc ast i ng. Mac hi neal l owance:1. 53mm Bul kdef or mat i onpr oc ess :Rol l i ng,f or gi ng,ex t r us i on,wi r e &bardr awi n g.Adv ant agesofsheetmet al :Hi ghs t r engt h. Gooddi mens i o nal acc ur ac y .Goods ur f acefi ni s h. Ec onomi calf ormassp r oduct i on. >6pl at e

me t alpr o per t y

casting

I nv es t mentCas t i ng Waxpat t er nspr oduc ed.Sever al pat t er ns at t ac hedt os pr uef or mi ngpat t er nt r eewhi c hi s t henc oat edwi t hat hi nl ay erofr ef r act or ymat er i al . Ful l mol df or med bycover i ngt hecoat edt r eewi t hsuffic i entr ef r act or ymat er i al maki ng i t r i gi d.Mol dh el di nani nv er t edposi t i on&heat edt omel t waxf ori tt o dr i poutofc av i t y .mol dpr eheat edt ohi ght emp,mol t enme t al i s pour ed,&i ts ol i di fies.mol dbr ok enawayf r om fi ni shedcast i ng,par t s s epar at edf r om t hes pr ue.

Advant ages:Par t sofgr eatcompl exi t y&i nt r i cac yc anbe c ast . Cl os edi mens i onal c ont r ol&g oods ur f ac efini sh. Waxcanus ual l yb er eco v er edf orr eus e.Nets hape mi t at i ons :Man yp r oc es s i ngst epsar er equi r ed. pr oces s.Li Rel at i v el yex pens i v epr oces s. Per manentmol dcas t i ng mol dpr eheat ed&c oat edf orl ubr i cat i on&heat di ss i pat i on.Cor esar ei nser t ed&mol di sc l osed.Mol t en me t alpour edi nt omol d,wher ei tsol i di fi es . Advant ages :Gooddi mens i onalc ont r ol &sur f acefi ni s h. Rapi ds ol i di fi cat i onc aus edbyt h eme t almol dr es ul t si na fi nergr ai ns t r uc t ur e,s ocast i ngsar es t r onger .L i mi t at i ons: Gener al l yl i mi t edt omet al sofl owerMP .Si mpl erpar t geomet r i esc ompar edt osandcast i ngduet ot heneedt o opent hemol d.Hi ghc ostoft hemol d.Co mmonl yMgAl , Cu,casti r on( notst e el) Hot c hambermac hi n e di ecl os ed&pl u ngerwi t hdr awn ,mol t e nmet al flowsi n t o c hamber .p l ungerf or cesmet ali nt hec hambert ofl owi nt o di e,mai nt ai ni ngpr ess ur edur i n gcool i ng&s ol i d i fi cat i on. Pl ungerwi t hdr awn,di eopened,&cas t i ngej ect ed. Zn,t i nl eadMg Col dc hamberDi eCas t i ng di ecl os ed&r am wi t hdr awn,mol t enmet al pour edi n t o c hamber .r am f o r c esmet al t oflow i n t odi e,mai nt ai ni ng pr es sur edur i ngc ool i ng&sol i di fi c at i on.r am wi t hdr awn , di eopened&par tej ect ed.Br ass ,Al , Mg al l o y Advant ages :Economi c al f orl ar gep r oduc t i onquant i t i es . Goodac cur acy&s ur f ac efi ni sh.Thi ns ec t i onspos si b l e. Rapi dc ool i n gme anss mal l gr ai ns i z eandgoodst r engt h oft h ecas tpr oduct .Li mi t at i ons:Gener al l yl i mi t edt o me t al sofl o werMP.Par tgeomet r ymus tal l ow r emov al f r om di e. Chi l l s :ext er nal chi l l sa ndi nt er nal chi l l s,enc our ager api dcool i ngof mat er i al satc r os ss ect i on Di r ec t i onals ol i di ficat i on:t ur bi nebl adesbyc hi l lpl at es,get t i ng c ol umi nanc r ys t al Gener alDef ect s Mi s r un:c as t i ngt hats ol i di fiedbef or ecompl et el yfil l i ngt he mol dcavi t y .Col ds hut :2por t i onsofmet al flow t oget herbutt her ei s l ac koff us i onduet opr emat ur ef r eez i ng.Col ds hot :Met al spl at t er s dur i ngpour i ngl eadi ngt of or mat i onofs ol i dgl obul eswhi chbec ome ent r appedi nt hec ast i ng.Shr i nk agecavi t y :Depr es si oni nsur f ac eor i nt er nal voi dc ausedbysol i di fi cat i ons hr i nkaget hatr es t r i ct st he amountofmol t enmet alav ai l abl ei nl astr egi ont of r eez e. Mi cr opor os i t y :s mal lv oi dsdi st r i but edt hr oughoutt hec ast i ngduet o l oc al i seds ol i di fi cat i onshr i nkageoffi nalmol t enmet al wi t hi n dendr i t i cs t r uct ur e.Hott ear s:c ast i ngr est r ai nedf r om c ont r ac t i on duet omol ddur i ngfi nals t agesofs ol i di ficat i onorear l ys t ageso f c ool i ng. Sandc ast i ngdef ect s

( 1) :depr es si onmadeb ypunchb ef or ec ut t i ng.( 2) : smoot hr egi o nr es ul t i ngf r om penet r at i onofpunc hbef or e f r act ur e.( 3) :r el at i vel yr oughs ur f ac ec ausedbyf r ac t ur e ofmet alasp unc hgodown.( 4) :shar pc or nerc ausedby el ongat i onofmet al dur i ngfi nal s t ageofsepar at i on. Cl ear anc e,c=at

F=S t L=0.7 (TS)t L As s umpt i ons:negl ec tmi noreffec tofcl ear anc ei n cal cul at i ngL( per i met er ) .Ent i r el engt hi smadeatt he samet i me( max i mum c ut t i ngf or c ec al cul at e d) . Vbendi ng:Lowpr oduc t i onquant i t y .Vdi esar esi mpl e andi nex pensi v e.Edgebendi ng:Hi ghpr oduc t i onquant i t y . Di esar emor ec ompl i c at edandcost l y .

α (R+ 360 if R2 t , K ba K bf ( Ten MAX bending force, F= L=L1 +A b + L2 A b=2 π

V −bending , K bf =1.33 ; edge be Spr i ngback :↓ i nbend∠ &↑ i nbendr adi us .When bendi ngpr es sur ei sr emov ed,el as t i cener gyr emai nsi n bentpar t ,causi ngi tt or ec ov erpar t i al l yt owar di t sor i gi nal mpensat i on:ov er bendi ng&bot t omi ng. shape.Co

Drawing clearance , C=1.1 t Dr awi ngf eas i bi l i t y:

DR≤ 2.0 ; r ≤ 0.5 ; Wher e:

DR=

t >1 % Db

Db Dp

D (¿ ¿ b−D p ) Db r =¿

Db^2=Dp^2+4Dph

Effec tofbl ank hol derf or ce: t o ohi gh:pr ev ent smet al hF f r om flowi ngi nt odi ec av i t y;ma yc aus et ear i ngduet o st r et c hi ngofmet al .Fh t o ol o w: Caus eswr i nk l es .

Dr awi ngFor ce,

Def ect si ni nj ect i onmo l d i ng:Shor tshot :Mol di nghas s ol i di fi edbef or ecompl et i on.Fl as h:Pol y mermel t squeez esi nt ot hepar t i ngs ur f ac eorar oundej ect i onpi ns. Si nkmar k s&v oi ds :Us ual l yduet ot hi ckmol ded s ect i onswher ei nsuffic i entmat er i al t ocompens at ef or s hr i nk age.Wel dl i ne:Pol y merfl owsar oundacor eor ot h erc onv exsec t i on&meet sf r om oppos i t edi r ec t i ons. Compr es si onmol di ng:char gei sl oaded,char gei s c ompr ess ed&cur ed,par ti sej ect ed&r emoved. Advant ages :Si mpl ert h ani nj ect i onmol ds .Nos pr ue& Y=yi el ds t r engt h( MPa) ;Rd =di ec or nerr adi us( mm) r unners y st e mi nacompr es si onmol d.Li mi t at i ons:l i mi t ed Def ect si ndr awi ng:wr i nk l i ngocc uri nfl ange/ wal l .Tear i ngduet ohi gh t os i mpl erpar tgeomet r i esduet ol owe rfl ow c apabi l i t i es TSt hatc aus et hi nni ngandf ai l ur e.Ear i ng( duet oani sot r opy) . oft her mos et t i ngmat er i al s.Mol dmus tbeheat ed,usual l y Sur f aces cr at c hesd uet opoorl ubr i cat i on,punch/ di enots moot h. b y e l e c t r i c r e s i s t a n c e , s t e a m, o r h o t o i l c i r c u l a t i o n . Redr awi ng/ Re ver sedr edr awi ng Ty pi c al ’ el ect r i cpl ugssoc ke t shousi ngpl at es / / Pl as t i cs hapi ng: unl i mi t edgeomet r y ; nets hape; l es sener gy Pott r ansf ermol di ng:c har gei sl oadedi nt opot .Sof t ened i sr equi r edl owT;nopai nt i ng pol ymerpr es sedi nt omol dcav i t y&cur ed.Par ti sej ect ed. DI ESWELL Pl ungert r ans f ermol di ng:char gei sl oadedi nt ot hepot . Ext r udedpol y mer" r mb" Sof t enedpol ymeri spr es s edf r om t heheat edwel l i t spr ev i ouss hapewhen l at e r al l yi nt omol dc av i t y&cur ed.Thepar ti sej ec t ed. i nt hel ar ger Bot hpr oc esspr oducedsc r ap,c al l edc ul lwhi chcannotbe c r osss ec t i onofe xt r uder , r ec ov er ed.T r ansf ermol di ngc apabl eofmol di ngmor e &t r i est or et ur nt oi t i n t r i c a t e p a r t s c o mp a r e d t o c o mp r e s s i o n . c u z ent ercavi t y af t erl ea vi n gt hedi eor i fi c e. asfl ui d,butnotascompl i cat edasi nj ect i on Ext r uderScr ew: Feed:f eedst oc kmovedf r om hopper& B l o w mo l d i n g : F a b r i c a t i o n o f a s t a r t i n g t u b e , c a l l e d a pr eheat ed.Compr es si on:pol y mert r ans f or medi nt ofl ui d, par i s on.I nfl at i onoft het ubet odesi r edfi nals hape. ai rmi xedwi t hpel l et si sex t r act edf r om mel t ,&mat er i al t r usi onbl ow mol di ng:Ex t r usi o noft hepar i son,par i son e r i ng:mel ti shomogeni z ed&s uffici ent Ex c ompr ess ed.Met i spi nc hedatt op&seal edatbot t om ar oundame t albl ow pr essur edev el opedt opumpi tt hr oughdi eopeni ng . pi nast het wohal vesoft hemol dc omet o get her ,t het ube Scr eenpac k:s er i esofwi r emeshess uppor t edby i si nfl at e dsot hati tt akest hes hapeoft hemol dcavi t y& as t i ffpl at ec ont ai ni ngs mal lax i al hol es .Funct i ons :Fi l t er t hemol di sopenedt or emov et hes ol i di fi edpar t . outc ont ami nant s&h ar dl umps.Bui l dpr es sur ei n I nj ec t i onbl owmol d i ng:Par i s oni si nj ec t i onmol ded me t er i ngs ec t i on.St r ai ght enfl ow o fpol ymermel t& ar oundabl owi n gr od,t hei nj ect i onmol di sopened&t he r emovei t s" memor y "ofc i r c ul armot i onf r om par i s oni st r ans f er r edt oabl owmol d,t hesof tpol y meri s Mol dc l os ei nj ect r et r act ej ect i nflat edt oc onf or mt ot hebl ow mol d&t hebl owmol di s Hol l ow pr ofi l e:needt obl ow ai r o p e n e d & b l o w n p r o d u c t r e mo v e d . 3pl at emol d:Us es3pl at es St r et chedbl ow mol di ng:I nj ect i onmol di ngoft he t os epar at epar t sf r om s pr ue Par i son,St r et c hi ng,Bl owi ng. &r unnerwhenmol dopens. Vacc um t her mof or mi ng:fl atpl a s t i csheetsof t enedb y Advant ages :Asmol dopens, heat i ng ,s of t e neds heetpl ac edov erc onc av emol dcav i t y , r unner&par t sdi s c onnect& v a cuum dr awst hes heeti nt ot hec avi t y .Pl as t i char dens dr opi nt o2c ont ai ner sunder onc ont ac twi t ht hec ol dmol dsur f ac e,&par ti sr emov ed mol d.Al l owsaut ooper at i on &s ubs equent l yt r i mmedf r om t heweb. ofmol di ngmachi ne. Pr ess ur et her mof or mi ng:+v epr ess ur ei nt r oducedatt op pushi ngheat eds heeti nt oc av i t y ,whi l ev acuum ( 1at m) dr awssh eeti nt ocavi t y .Hi gherpr es sur e( 3t o4at m)c an beused( vacuum l i mi t edt o1at m) . TwoPl at emol d Mec hani cal t her mof or mi ng:+v emol dpushesheat ed sheeti nt oca vi t y . Bet t erdi mensi onal cont r ol ,s ur f ac e det ai l sonbot hs i des.2mol dhal v es ,mor ec ost l y . Onl yt her mopl ast i c scanbet her mof or medas t her moset t i ng/ el as t omer sha veal r eadybeenc r os sl i nked andc annotbesof t enedb yr eheat i ng. Wel di ngcoal es cedatt hei rc ont ac t i ngs ur f acebyappl yP orF/ j oi ni ng( mec hani cal l yf a s t en) Fus i onwel di ng:j oi ni ngpr oc esst hatmel t sbasemet al . Fi l l ermet al addedt omol t enpool t of ac i l i t at epr oc ess& pr o vi debul k&addedst r engt ht owel dedj oi nt .Aut ogenous wel d( nofi l l erme t alused)

(

)

Db F=π D p t ( TS ) −0.7 Dp 0.015 Yπ Fh = {Db2−( D p+2.2t + 4

i mi nat essol i di fic at i onofs pr ue&r unnerby Hotr unnermol d:El l oc at i ngheat er sar oundt hec or r espondi ngr unnerc hannel s .Whi l e pl ast i ci nt hemol dcavi t ys ol i di fies,mat er i ali nspr ue&r unner c hannel sr emai nsmol t e n,r eadyt obei nj ec t edi nt ocavi t yi nnext c yc l e. Adv ant ages:Sav esmat er i alt hatot her t oper at i on Fact or saffect i ngs hr i nkage:I nj ect i onp

Shrinkage , D c =

P A Unit heat for welding , U m=K T Power Density , PD=

Mol di ngt emp;Par tt hi c kness

S

−6

K=3.33 x 10 T m =melting temp (f 1 f 2 EI ) V ( mm / s )= Um Aw 3

A w V =WVR (mm / min ) U m ( WVR) =f 1 f 2 HR=U m A w V

Spotwel di ng Usedf orl apj oi nt Gr oov ewe l ds/Fi l l etWel d T y pesofFl ames Neut r alFl ame:r at i oofacet y l enet ooxy geni s1: 1. Ox i di zi ngfl ame:Gr eat e ro xy gensuppl y .Har mf ul ex cept f orCuandCubasedal l oy s.Reduc i ng( c ar bur i zi ng) at i oofox y geni sdefi c i ent .T empi sl ow.Nor mal l y fl ame:r us edf o rbr azi ng,s ol der i ng,&flamehar deni ng.

Fl ux:pr ev ent sf o r mat i onofox i des&ot h erc ont ami nant s i nwel di ng,ordi ss ol v est hem &al l owsr emoval .Pr ovi des pr o t ec t i v eat mos pher ef orwel di ng.St abi l i z esar c . Reducesspat t er i ng.Submer ged:hi ghdepos i tr at e Sol i dSt at eWel di ng:Nofi l l ermet aladded,nomel t i ngof basemet al .Coal es cencer es ul t sf r om acombi nat i onof es sFac t or s:2 heat&pr es s ur eorpr ess ur eal one.Succ f ay i ngsur f ac esmustbev er ycl ean&i nv er yc l ose ph ys i c alc ont actwi t heachot hert oper mi tat omi c ages :noheataffec t edz one,met al bondi ng.Advant ar oundj oi ntr et ai nsor i gi nalpr oper t i es.Pr oduc eswel ded j oi nt st ha tbondent i r ec ont acti nt er f acebet ween2par t s r at hert h anatdi st i nctsp ot sorseams.Usedt obond di ss i mi l armet al s ,wi t houtc onc er nsaboutr el at i v eMP , t her mal expans i ons ,&ot herpr obl emst h atar i sei nFW. Ul t r as oni cWel di ng 2c omponent shel dt oget her ,&os ci l l at or ysh ears t r es s es oful t r asoni cf r equenc yappl i edt oi nt e r f acec aus e c oal esc enc e.Osc i l l at or ymot i onbr eaksdownanys ur f ac e fi l msal l owi ngi nt i mat ec ont ac t&s t r ongmet al l ur gi ca l bondi ngb et weensur f ac es.Al t houghheat i ngofsur f ac es occ ur s ,t empar ewel l bel owTm.Nofi l l erme t al s ,fl uxes orshi el di nggas es .Li mi t edt ol apj oi nt sons of tma t er i al s s uc hasal umi ni um &c opper . Fr i ct i onWel di ng Coal es c enc ei sac hi ev edb yf r i ct i onal heat&pr es sur e.No mel t i ngoc cur satf ay i ngsur f aces.Nofi l l erme t al ,fl ux,or s hi el di ngg asesus ed.Pr oces sy i el dsanar r ow HAZ. Di s si mi l a rmet al sc anbej oi ned.Wi del yus edc ommer ci al pr oc ess ,aut omat i on&mas spr oduc t i onpos s i bl e.Si zeof wel dz onedependsonamountofh eatgener at ed. Ther malc onduc t i v i t yofmat er i al s.Mec hani c alpr oper t i es ofma t er i al satel evat edt emper at ur es . Res i s t anc eSpotWel d i ng Fusi onwel di ngpr oc es swh er ecoal esc encei sachi ev eby combi nat i onofheat&pr ess ur e.Heati sgener at edby el ec t r i c al r es i st ancet oc ur r entfl ow ati n t er f aceof2par t s

t obewe l ded.Fusi onoft hebas emet ali sac hi e vedatone l oc at i onbyopposi ngel ect r odes .

2

Heat generated , H =I Rt I =5,000 ¿ 20,000 A ;V...