Qhov tseem ceeb ntawm Preheating ua ntej Vuam thiab kev kho cua sov tom qab vuam

Preheating ua ntej welding
Preheating ua ntej vuam thiab kev kho cua sov tom qab vuam yog qhov tseem ceeb heev los xyuas kom meej qhov zoo ntawm vuam. Vuam ntawm cov khoom tseem ceeb, vuam ntawm cov hlau alloy thiab vuam ntawm cov tuab tuab yuav tsum tau preheating ua ntej vuam. Lub luag haujlwm tseem ceeb ntawm preheating ua ntej vuam yog raws li hauv qab no:
(1) preheating tuaj yeem ua kom qis qis qis tom qab vuam, yog qhov tsim nyog rau kev khiav tawm ntawm diffusion hydrogen hauv cov hlau vuam, kom tsis txhob muaj hydrogen tawg. Nyob rau tib lub sij hawm kuj txo cov degree ntawm hardening ntawm weld thiab tshav kub-cuam tshuam cheeb tsam, kev txhim kho qhov tawg tsis kam ntawm welded pob qij txha.
(2) Preheating txo welding kev nyuaj siab. Uniform hauv zos preheating lossis tag nrho cov preheating tuaj yeem txo qhov kub ntawm qhov sib txawv ntawm cov khoom ua haujlwm welded hauv thaj chaw vuam (tseem hu ua kub gradient). Qhov no txo ​​qhov kev ntxhov siab ntawm vuam ntawm ib sab, thiab ntawm qhov tod tes, txo cov vuam strain tus nqi, uas yog qhov tsim nyog kom tsis txhob vuam tawg.
(3) Preheating tuaj yeem txo qhov kev txwv ntawm cov qauv welded, tshwj xeeb tshaj yog pom tseeb rau kev txo qis kev txwv ntawm lub ces kaum sib koom ua ke, nrog rau qhov nce ntawm preheating kub, tawg qhov tshwm sim txo.
Preheating kub thiab interlayer kub xaiv tsis yog tsuas yog hais txog cov tshuaj muaj pes tsawg leeg ntawm hlau thiab vuam pas nrig, tab sis kuj nrog rigidity ntawm welded qauv, vuam txoj kev, ambient kub, thiab lwm yam, yuav tsum tau txiav txim siab tom qab txiav txim siab rau cov yam ntxwv no. Tsis tas li ntawd, lub uniformity ntawm lub preheating kub nyob rau hauv cov kev taw qhia ntawm steel phaj thickness thiab lub uniformity nyob rau hauv lub weld cheeb tsam muaj ib tug tseem ceeb lub luag hauj lwm rau qhov txo ntawm vuam kev nyuaj siab. Qhov dav ntawm lub hauv paus preheating, yuav tsum yog raws li cov kev txwv ntawm welded workpiece, feem ntau yuav tsum yog peb npaug ntawm phab ntsa thickness nyob ib ncig ntawm lub weld cheeb tsam, thiab yuav tsum tsis txhob yuav tsawg tshaj li 150-200 hli. Yog hais tias lub preheating tsis sib xws, tsis tsuas yog tsis txo cov vuam kev nyuaj siab, tab sis yuav tshwm sim ua rau kom cov vuam kev nyuaj siab.

2 tom qab vuam cua sov kho
Lub hom phiaj ntawm kev kho cua sov tom qab vuam muaj peb yam: kev tshem tawm hydrogen, tshem tawm kev ntxhov siab ntawm vuam, txhim kho lub koom haum thiab kev ua tau zoo ntawm cov vuam.
Tom qab vuam hydrogen tshem tawm kev kho mob, hais txog tom qab ua tiav ntawm vuam, lub vuam tseem tsis tau txias kom qis dua 100 degree, kev kho cua sov qis. General specifications rau cua sov rau 200 ~ 350 degree, rwb thaiv tsev 2-6 teev. Lub luag haujlwm tseem ceeb ntawm kev xa tawm tom qab vuam dehydrogenation yog txhawm rau txhawm rau txhawm rau khiav tawm ntawm hydrogen hauv thaj chaw vuam thiab tshav kub, rau kev tiv thaiv ntawm cov hlau tsis tshua muaj hlau vuam vuam tawg yog qhov zoo heev.
Nyob rau hauv cov txheej txheem vuam, vim qhov tsis sib xws ntawm cov cua sov thiab cua txias, nrog rau cov khoom siv nws tus kheej los tsim cov kev txwv lossis kev txwv sab nraud, thaum kawg ntawm kev ua haujlwm vuam, nyob rau hauv cov khoom yuav ib txwm tsim vuam kev nyuaj siab. Lub xub ntiag ntawm weld stresses nyob rau hauv cov tswv cuab yuav txo tau qhov tseeb load-bearing muaj peev xwm ntawm lub welded ob leeg cheeb tsam, tsim yas deformation thiab, nyob rau hauv loj heev mob, ua rau kev puas tsuaj ntawm cov tswv cuab.
Kev ntxhov siab rau kev kho cua sov yog ua kom cov welded workpiece ntawm qhov kub thiab txias, nws lub zog tawm los txo qis, kom ua tiav lub hom phiaj ntawm kev so ntawm vuam kev ntxhov siab. Muaj ob txoj hauv kev uas feem ntau siv: ib qho yog tag nrho cov kub-kub tempering, uas yog, lub vuam tag nrho rau hauv lub qhov cub cua sov, maj mam rhuab mus rau qhov kub thiab txias, thiab tom qab ntawd tuav rau ib lub sij hawm, thiab thaum kawg txias nyob rau hauv lub qhov cub. cua los yog hauv qhov cub. Nrog rau txoj kev no tuaj yeem tshem tawm 80% -90% ntawm kev ntxhov siab vuam. Lwm txoj kev yog lub zos kub-kub tempering, uas yog, tsuas yog cov weld thiab nws cov cheeb tsam nyob ze yog rhuab, thiab ces maj mam txias kom txo tau lub ncov ntawm lub vuam kev nyuaj siab, thiaj li hais tias qhov kev nyuaj siab faib yog tus du, mus ua si ib feem nyob rau hauv lub siab. tshem tawm lub hom phiaj ntawm vuam kev nyuaj siab.
Qee cov ntaub ntawv hlau alloy tom qab vuam, nws cov welded pob qij txha yuav tshwm sim hardened lub koom haum, thiaj li hais tias txhua yam khoom ntawm cov khoom deterioration. Tsis tas li ntawd, lub koom haum hardened no nyob rau hauv lub vuam kev nyuaj siab thiab lub luag hauj lwm ntawm hydrogen, tej zaum yuav ua rau kev puas tsuaj ntawm kev sib koom tes. Yog tias tom qab kev kho cua sov, lub koom haum metallurgical ntawm kev sib koom ua ke tau txhim kho, txhim kho cov yas thiab tawv ntawm cov welded sib koom ua ke, yog li kev txhim kho cov khoom siv sib txuas ntawm cov khoom sib txuas.