Cov yam ntxwv cuam tshuam rau qhov raug ntawm castings

Nyob rau hauv ib txwm muaj xwm txheej, qhov tseeb qhov tseeb ntawm precision castings raug cuam tshuam los ntawm ntau yam xws li cov qauv casting, cov khoom siv casting, molding, plhaub ua, roasting, pouring, thiab lwm yam, thiab ib qho ntawm cov kev sib txuas tau teeb tsa thiab ua haujlwm tsis tsim nyog yuav hloov tus nqi shrinkage. ntawm qhov casting, uas ua rau muaj qhov sib txawv ntawm qhov tseeb qhov tseeb ntawm qhov casting thiab qhov yuav tsum tau ua. Cov hauv qab no yog cov yam ntxwv uas tuaj yeem ua rau qhov tseeb qhov tsis xws luag hauv precision castings:

(1) Kev cuam tshuam ntawm cov qauv casting: a. Lub phab ntsa thickness ntawm lub casting yog loj, thiab phab ntsa ntawm casting yog nyias, thiab shrinkage yog me me. b. Tus nqi shrinkage dawb yog loj, thiab tus nqi hindered shrinkage yog me me.

(2) Kev cuam tshuam ntawm cov khoom siv casting: a. Qhov siab dua cov ntsiab lus carbon nyob rau hauv cov khoom, qhov me me ntawm linear shrinkage, thiab cov ntsiab lus carbon tsawg dua, qhov ntau dua linear shrinkage. b. Lub casting shrinkage ntawm cov khoom siv yog raws li nram no: casting shrinkage K=(LM-LJ)/LJ × 100%, LM yog kab noj hniav loj, LJ yog qhov loj casting. K yog cuam tshuam los ntawm cov hauv qab no: ciab pwm K1, casting qauv K2, alloy hom K3, pouring kub K4.
(3) Kev cuam tshuam ntawm pwm ua rau ntawm qhov shrinkage tus nqi ntawm cov kab casting: a. Qhov cuam tshuam ntawm kev txhaj tshuaj wax kub, wax txhaj tshuaj siab thiab tuav lub sij hawm ntawm qhov loj ntawm cov pwm peev yog qhov pom tseeb tshaj plaws nrog rau qhov kub thiab txias, ua raws li kev txhaj tshuaj ciab siab, thiab lub sij hawm tuav tsis tshua muaj feem cuam tshuam rau qhov kawg ntawm qhov loj me. peev pwm tom qab ua tiav cov peev txheej molding. b. Cov linear shrinkage ntawm wax (pwm) cov khoom yog hais txog 0.9-1.1%. c. Thaum lub peev pwm khaws cia, nws yuav txo qis ntxiv, thiab nws cov nqi shrinkage yog kwv yees li 10% ntawm tag nrho cov shrinkage, tab sis thaum nws khaws cia rau 12 teev, qhov loj ntawm cov peev pwm yog qhov ruaj khov. d. Lub radial shrinkage ntawm cov quav ciab pwm tsuas yog 30-40% ntawm qhov shrinkage nyob rau hauv qhov ntev kev taw qhia, thiab lub zog ntawm cov wax txhaj tshuaj kub nyob rau hauv lub free shrinkage yog ntau ntau dua li qhov cuam tshuam ntawm cov hindered shrinkage (cov tshuaj siv quav ciab kub. yog 57-59 degree, qhov kub thiab txias, qhov ntau dua qhov shrinkage).

(4) Kev cuam tshuam ntawm cov khoom siv plhaub: kev siv zircon xuab zeb, zircon hmoov, Shangdian xuab zeb, Shangdian hmoov, vim nws qhov me me expansion coefficient, tsuas yog 4.6 × 10-6 / degree, yog li nws tuaj yeem tsis quav ntsej.

(5) Kev cuam tshuam ntawm lub plhaub roasting: vim qhov me me expansion coefficient ntawm lub plhaub, thaum lub plhaub kub yog 1150 degree, nws tsuas yog 0.053%, yog li nws tseem tuaj yeem tsis quav ntsej.

(6) Kev cuam tshuam ntawm qhov kub thiab txias: qhov kub ntawm qhov dej ntau dua, qhov ntau dua qhov shrinkage, thiab qhov kub ntawm qhov pouring qis dua, qhov me me ntawm qhov shrinkage, yog li qhov ntsuas kub yuav tsum tsim nyog.