CNG NGH CH TO PHI I. Cng ngh c l g? c l mt phng php to ra vt phm in hnh bng cch nu chy kim loi rI em rt vo khun lm sn, sau khi kim loi ng c v ngui lnh s cho ta mt sn phm c hnh dng v kch thc tng ng chi tit ta cn gia cng. II. Cu to v cng dng ca b mu: B mu: g, kim loI mu nh nhm, ng -Yu cu khi chn g: mm, nh, t ht m, khng b cong vnh khi thI tit thay i. -Cng dng: to ra lng khun, th hin ng bao ngoi c hnh dng v kch thc tng ng chi tit ta cn gia cng. -Nu chi tit cn lm rng th phI c tai gI mu -Sn phn bit mu (: hnh dng chi tit; en: tai gI mu). III. Hp li -Cng dng: hp li mc ch to li, hnh dng v ng nt trong lng hp li,th hin hnh dng trong lng chi tit cn lm li -Hnh dng hp li ging ht hnh dng lng chi tit -Hnh dng li ging nhng ngc chiu vI hnh dng lng chi tit -Thnh phn hn hp lm khun: Ch yu l ct thch anh (75%-85%): yu cu phI sch, c ht khng ng u, c tnh cht bn nhit cao (khi nhit cao khng b chy, v vn) Cht dnh kt: thng thng s dng cao lanh (t st) (8%-16%) Yu cu: nguyn cht, dnh kt cao khi gp nc Ngoi ra cn s dng cc cht dnh c bit; du thc vt, nc thu tinh long, mt ma,( 3%-5%),thng s dng trong trng hp lm khun v li c tnh cht phc tp Cht ph gia: bt than, bt g, bt graphit (3%-5%) c tc dng tng xp cho hn hp, bo v b mt long khun bong nhn. IV. 1. Nc: 4%-8%

Quy trnh cng ngh lm khun v lm li: Lm khun: 3 bc +Bc 1: lm khun dI Trc khi lm khun ngI ta trn u hn hp lm khun, sau lm mt phng h mu; ri dung chy d xung quanh mu tng I cht,sau b tip ln mt lp hn hp dy khong 100-150mm ,d cht.Nu chiu cao mu cng cao th ngI ta cng b nhiu lp n giI hn mt phn khun ri dng thc gt phng b mt v ly bay l tng I nhn. +Bc 2: lm khun trn Ngi ta ph ln b mt khun di mt lp mng ct phn khun rI lp na mu vo v y hm khun trn ln. Sau b tr ton b h thng rt v ng thot hi.

Nguyn tc b tr: H thng rt -Rnh dn kim loi c t ti cc im c thnh mng nht so vi tng th chi tit (1 rnh,2 rnh,). m bo khng lm chn ng lng khun gy soi v v phi m bo thi gian ng c. -ng rt b tr lch so vI rnh dn kim loi H thng thot hi -B tr cc nh cao nht -Nu cc chi tit co tit din b mt ln, chnh lch dy mong ln ngi ta b tr cc ng hi ti cc v tr tit din ln v dy Sau khi b tr xong cho hn hp vo hm khun v tin hnh thao tc nh lm khun di Sau lm xong khun trn ng cc nh v vo cc gc ca hm khun,xm kh RI rt ton b cc mu h thng rt, h thng thot hi ra rI nng hm khun trn ln tin hnh ly mu +Bc 3: rt mu v sa cha lng khun Trc khi rt mu tin hnh nh ng mu to ra khe h.Sau cm vo trng tm ri mt di ly mu ri rt mu ln theo hpng thng ng v gi thng bng. Sau khi ly mu ngi ta dng ngh thch hp sa cha lng khun lp mng graphit. 2. Quy trnh lm li: Cho hn hp vo hp li v xng rut lun nm gia theo tng lp v d cht,sau ly rut ra phi kh ri dung nc sn sn ln cc b mt n (t st, bt graphit, v nc) sn xong a vo t sy (8h / 1500- 2000) V. Nu luyn 1.Thnh phn nhin liu v vt liu kim loi: Nhin liu: ch yu phc v cho l nu gang l than cc, than (than gy) Than cc: chy tt, thong, tiu khng bao gi v vn Nu s dng than ngi ta phi thc hin quy trnh than mc ch tng tnh bn nhit cho n. Vt liu kim loi:ch yu l gang -Gang thi: 40-50 %/ m liu -Gang vn: l cc thit b chi tit b h hng 30-40 % -Gang hi liu: gang tha trong x nghip nu ( h thng rt, hi 15-30% -Ngoi vt liu kim loi s dng cc thnh phn tr dung: + vi: 4-6 % to x trong qu trnh nu +Cc hp kim phero ( phero mangan, phero silic ) chim 3-5% mc ch thay i thanh phn c tnh nc gang 2.Quy trnh nu chy kim loi: Cho ci vo ni l khong 1-2 kg v t chy ln, sau vo mt lp than n hng ngi ta tip tc s than cn li theo mc quy nh c tnh t

mt gi chnh o ln khong 900, ri bt ton b h thng mt gi v l ra x. Thi gian than khong 10h. Sau thi gian xp m liu kim loi vo v lp than vo theo th t n y l.Xong thng h thng mt gi ng thi chy qut gi, sau thi gian gang bt u chy long ri xung ni l ngi ta tin hnh bt l ra gang. Sau khong 10 pht thng l ra gang cho vo ni rt, khi y ni ngi ta bt l ra gang v khing vo rt khun. Qu trnh lp i lp li n xong khi lng cn thit *Ghi ch: trong khi nu gang vt liu kim loi phi m bo lun lun y l v thng xuyn cho x chy ra. K THUT HN Thc cht v c im: 1. Thc cht: Hn l phng php ghp ni 2 hay nhiu chi tit bng kim loi li vi nhau m khng th tho ri, bng cch nung kim loi n trng thi chy hoc do sau nh s ngui v ng c to nn mi hn lin kt kim loi hoc dung p lc ln 2. c im: -Tit kim c kim loi so vi tn rive t 10-20%,so vi phng php c t 3050% -C th to c cc kt cu nh c kh nng chu lc cao -C th hn 2 hay nhiu kim loi c tnh cht khc nhau - bn v st kn ca mi hn ln -Trong vt hn cn tn ti ng sut d ln, kh nng chu ti trng ng thp (tuy nhin kt cu mi hn kh tt khi chu ti trng tnh) II. Cc phng php hn: phn theo hai nhm c bn -Hn nng chy: kim loi mp hn c nung n trng thi nng chy kt hp vi kim loi b sung t ngoi vo in y khe h gia hai chi tit hn, sau ngui v ng c to nn mi hn. nhm hn ny gm: hn h quang, hn kh, hn in x, hn plasma, hn bng tia laze, hn bng tia in t. -Hn p lc: khi hn bng p lc kim loi vng mp hn c nung n trng thi do,sau dung mt p lc ln to nn mi lin kt kim loi nhm hn ny gm: hn in tip xc, hn masat, hn n, hn siu m, hn cao tn, hn khuch tn III. Hn h quang 1. Thc cht: l phng php hn nng chy s dng nhit ca ngn la h quang sinh ra gia cc in cc hn, v thc cht h quang hn l dong chuyn di ca cc in t v ion trong mi trng kh gia hai in cc hn, n km theo s pht nhit ln v pht sng mnh. 2. Phn loiI.

-Theo dng in +Dng in hn xoay chiu : cht lng mi hn khng tt v cng dng in khng n nh + Dng in hn mt chiu: cht lng mi hn tt hn, d gy h quang, d hn, cng dng in n nh, xong t c s dng v gi thnh t. -Theo in cc hn +in cc hn khng nng chy: c ch to t vt liu c nhit nng chy cao nh graphit, vonfram

u c vt cn, b sung lim loi cho mi hn phi s dng que hn ph +in cc hn nng chy(que hn): c ch to t kim loi hoc hp kim c cng thnh phn vi tahnh phn kim loi vt hn. Cu to:

ng knh que hn l thuyt:1-12mm ng knh que hn thc t :1-4mm Chiu di phn cp :l1=30mm Chiu di que hn :L=350-450mm Lp thuc bc que hn c ch to t hn hp dng bt gm nhiu lai vt liu kim loi trn u vi cht kt dnh bc ngoi li c chiu dy t 1-2mm .Tc dng ca lp thuc bc que hn: -Tng kh nng ion ha d gy h quang v duy tr h quang n nh, thng thng a vo thuc bc hp cht kim loi kim Bo v mi hn trnh s oxi ha hoc ha tan khi vo mi trng To phu hng kim loi vo vng hn, to x lng v uche ph mi hn lm gim tc ngui mi hn trnh nt. -Kh oxi trong qu trnh hn ngi ta a vothnh phn thuc bc cc phero hp kim hoc kim loi sch c i lc mnh vi oxi, c kh nng to oxit d tch khi kim loi lng. IV. Cc loi my hn: 1. Cc loi my bin p hn xoay chiu: -My hn xoay chiu iu chnh cng dng in bng li t di ng

Nguyn l: Theo s nguyn l trn y l loi my hn iu chnh cng dng in bng li t di ng. My hn kiu ny c mt li t di ng A nm trong gong t B ca my bin p. Khi li t A nm hon ton trong gng t B th t thng do cun th cp sinh ra c mt phn r nhnh qua li t lm cho t thng qua cun th cp gim in p trn cun th cp gim. Khi li t dch ra ngoi theo phng vung gc vi mt phng ca gng t B, khe h gia li t v gng t tng ln, t thng r nhnh gim lm cho t thng qua cun th cp tng ln in p trn cun th cp tng My hn c li t di ng c kt cu gn, iu chnh dng din hn v cp, khong iu chnh rng do hin nay c s dng nhiu -My hn xoay chiu iu chnh cng dng in hn bng thay i s vng dy cun th cp:

Phn bit cun s cp- th cp: + ngun vo +tit din dy Nguyn l: dng kha K thay i s vng dy I tng bng cch gim s vng dy cun th cp,I gim bng cch tng s vng dy cun th cp 2. Cc loi my hn mt chiu: -My hn chnh lu ba pha S nguyn l:

-My hn bn t ng hn trong mi trng kh ba v CO2

Cu to: +My bin p hn chnh lu: SVI 300i +C cu cp li dy hn t ng Mig2F Bnh cha kh CO2: trn bnh cha c lp lu lng k iu chnh lu lng kh t trong bnh cha ra v lm n nh p sut kh trong qu trnh lm vic +M hn: c lp vi c cu cp li dy hn t ng. Nhim v m hn dung dn dy hn v kh trong qu trnh hn u im: hn mi hn y lien tc khng b ngt qung, cht lng mi hn tt v cng dng in n nh, b mt mi hn sch. V. Hn v ct kim loi bng kh O2 v C2H2 1. Thc cht v c im: Hn v ct bng kh l phng php hn nng chy s dng nhit ca ngn la sinh ra khi t kh chy chy trong dng kh oxi k thut, thng thng nht l hn v ct bng kh O2 v C2H2 Hn v ct bng kh c c im : hn c cc vt hn mng, hn c hai hay nhiu kim loi c tnh cht khc nhau v d nh hn gang, ng, nhm Nhc im:- Nng sut hn thp - Cht lng mi hn khng tt, do b nh hng nhit vt hn b co rt, cong vnh nhiu hn so vi hn h quang. 2. Thit b hn v ct kim loi bng kh O2 v C2H2 ( trm hn v ct kim loi bng kh O2 v C2H2) -Bnh cha kh O2: ch to bng thp tm, chiu dy: 7mm , bng phng php dp hoc hn c Dngoi=219mm, chiu cao H= 1390mm, c dung tch cha 40 lt, Plm vic=150 at. nhn bit bnh cha kh oxi sn mu xanh hoc xanh da tri -Bnh cha kh C2H2: c ch to bng thp tm, chiu dy 7mm, bng phng php dp hoc hn, c Dngoi=400mm, H=800mm, Plm vic