Dab tsi yog qhov cuam tshuam ntawm kev kho cua sov tom qab vuam ntawm cam khwb cia tooj liab hluav taws xob cua sov?

Thaum lub sij hawm welding txheej txheem ntawm cam khwb cia tooj liab hluav taws xob cua sov, vuam kev nyuaj siab yuav ib txwm tshwm sim nyob rau hauv lub Cheebtsam tom qab lub vuam ua hauj lwm tiav vim tsis sib xws cua sov thiab cua txias, raws li zoo raws li sab hauv los yog lwm yam kev txwv ntawm lub Cheebtsam. Lub xub ntiag ntawm vuam kev nyuaj siab nyob rau hauv lub Cheebtsam yuav txo tau lub tswv yim load-bearing muaj peev xwm ntawm lub vuam sib koom ua ke cheeb tsam, ua rau cov yas deformation, thiab txawm ua rau kev puas tsuaj rau lub Cheebtsam nyob rau hauv mob hnyav. Qee cov ntaub ntawv hlau alloy yuav raug kho kom tawv nqaij hauv lawv cov pob qij txha tom qab vuam, uas yuav ua rau cov khoom siv tsis zoo ntawm cov khoom siv. Tsis tas li ntawd, qhov txheej txheem hardening no yuav ua rau muaj kev puas tsuaj rau kev sib koom ua ke raws li qhov cuam tshuam ntawm vuam kev nyuaj siab thiab hydrogen. Yog hais tias lub cam khwb cia tooj liab hluav taws xob rhaub tau txais kev kho cua sov, cov txheej txheem metallographic ntawm cov pob qij txha yuav raug txhim kho, txhim kho cov yas thiab durability ntawm cov pob qij txha welded, thiab tom qab ntawd txhim kho cov khoom siv hluav taws xob inductive ntawm cov pob qij txha.
Thawj cov nyhuv ntawm preheating ua ntej welding rau cam khwb cia tooj liab hluav taws xob cua sov yog raws li nram no:
(1) Preheating nrog tooj liab casting hluav taws xob rhaub tuaj yeem ua kom qis qis qis tom qab vuam, pab txhawb kev khiav tawm ntawm cov khoom tawg hauv cov hlau vuam, thiab tiv thaiv qhov tshwm sim ntawm hydrogen induced tawg. Nws kuj txo qhov hardening degree ntawm weld thiab tshav kub-cuam tshuam cheeb tsam, thiab txhim kho qhov tawg tsis kam ntawm welded pob qij txha.
(2) Preheating tuaj yeem txo qhov kev ntxhov siab ntawm vuam. Uniform hauv zos preheating lossis tag nrho preheating tuaj yeem txo qhov sib txawv ntawm qhov kub thiab txias (tseem hu ua kub gradient) ntawm qhov chaw welded hauv thaj chaw vuam. Nyob rau hauv txoj kev no, ntawm ib sab, vuam kev nyuaj siab yog txo, thiab ntawm qhov tod tes, qhov vuam strain tus nqi txo, uas yog qhov zoo rau kev tiv thaiv qhov tshwm sim ntawm vuam tawg.
(3) Preheating tuaj yeem txo qhov nruj ntawm cov qauv vuam, tshwj xeeb tshaj yog rau cov pob qij txha. Raws li qhov kub ntawm preheating nce, qhov tshwm sim ntawm cov kab nrib pleb txo.
Cov teebmeem ntawm kev kho cua sov tom qab vuam ntawm cam khwb cia tooj liab hluav taws xob rhaub muaj xws li: tshem tawm cov thermal stress los ntawm vuam, sib sau ua ke ntawm kev sib txuas ntawm vuam thiab tshav kub-cuam tshuam cheeb tsam, refining lub grain ntawm weld thiab tshav kub-cuam tshuam cheeb tsam, tu lub hydrogen embrittlement ntawm weld thaum lub sij hawm vuam, thiab zoo fusion ntawm vuam hlau thiab lub hauv paus hlau tom qab kev kho cua sov (feem ntau cov qib steel ntawm vuam cov ntaub ntawv thiab lub hauv paus hlau yog inconsistent, thiab zoo dua ua ke yuav ua tau tiav tom qab tshav kub dispersion).