Induction cua sov welding seam tshav kub kho txoj kev

Pipeline steel yog hom hlau tseem ceeb uas nws cov welds xav tau kev kho cua sov los txhim kho cov khoom siv. Cov hlau siv nyob rau hauv cov qib steel sib txawv thiab lawv qhov yuav tsum tau muaj rau chav sov lub zog yog teev nyob rau hauv Table 6-2. Raws li cov hom hlau thiab cov khoom siv kho tshuab tau teev tseg hauv Table 6-2, cov txheej txheem kev kho cua sov tseem ceeb los txhim kho tag nrho cov kev ua haujlwm ntawm welds suav nrog kev kho kom zoo, normalizing + tempering kev kho mob, quenching + tempering kev kho mob thiab lwm yam. Tam sim no, kev kho cov vuam zoo feem ntau yog siv los tsim cov kav dej hauv tsev, thiab lwm txoj kev kho cua sov tseem tsis tau txais. Qhov kev kho cua sov siab tshaj plaws yog quenching thiab tempering ntau lawm kab. Normalizing kev kho mob feem ntau yog siv nyob rau hauv loj-scale welded yeeb nkab ntau lawm kab txawv teb chaws, thiab quenching thiab tempering kev kho mob tsuas yog siv los ntawm ib tug neeg lub tuam txhab nyob rau hauv Nyiv thiab European Union. Induction cua sov quenching thiab tempering kho ntawm welds yog cov kev taw qhia ntawm kev loj hlob yav tom ntej.

Table 6-2 Standard steel qib thiab chav tsev kub lub zog ntawm pipeline steel

(1) Weld induction cua sov normalizing kev kho mob suav nrog kev kho annealing, qee zaum hu ua kev ntxhov siab nyem annealing. Lub induction cua sov normalizing txheej txheem ntawm weld yog kom sov lub vuam mus rau qhov kub siab tshaj Ae, thiab tom qab ntawd cua-txias kom qis dua 400 ° C thiab dej-txias rau chav tsev kub tom qab 900 ~ 950 ° C. Nyob rau hauv txoj kev no, qhov kev ntxhov siab sab hauv ntawm cov vuam raug tshem tawm, cov nplej ntawm cov vuam yog ua kom zoo dua qub, cov txheej txheem microstructure tau txhim kho, thiab cov yas thiab qhov cuam tshuam ntawm cov vuam zoo tuaj. Weld induction cua sov normalizing kev kho mob yog tsim rau zoo tib yam low-alloy steel thiab ib co low-alloy high-strength steels, sib npaug rau welded kav hauv qab X60 steel qib. Lub vuam seam induction cua sov annealing kev kho mob yog kom sov lub vuam seam mus rau 700 ~ 750 ° C dual-theem cheeb tsam, thiab ces cua txias rau chav tsev kub, lub hom phiaj yog kom tshem tawm cov kev ntxhov siab nyob rau hauv lub vuam thiab txhim kho cov yas. Annealing kev kho mob feem ntau yog siv rau cov pa roj carbon steel thiab ib co zoo tib yam low-alloy steel welded kav. Cov txheej txheem no tsis tshua muaj siv nyob rau hauv domestic welded yeeb nkab ntau lawm kab.

(2) Weld induction cua sov normalizing + tempering kev kho mob Tom qab normalizing kev kho mob, thaum lub hardness ntawm weld tseem siab thiab cov yas tseem tsis tshua muaj, kub tempering kev kho mob yuav siv tau los kho nws. Induction cua sov thiab tempering yog kom sov cov vuam mus rau qhov kub hauv qab Ad, feem ntau yog nyob ib ncig ntawm 650 ℃ thiab ces cua txias. Tom qab qhov kub thiab txias tempering kev kho mob, cov qauv martensite nyob rau hauv cov hlau nyoos yog hloov mus rau hauv tempered sorbite thiab ferrite, lub plasticity ntawm cov weld zoo tuaj, hardness yog txo, thiab lub zog hloov me ntsis. Weld siv induction cua sov rauv quenching thiab tempering kho. kaum txoj kev kho cua sov no, tseem hu ua quenching, quenching thiab induction cua sov kab weld tshav kub kho yog cov cuab yeej tshaj plaws. Tom qab quenching thiab tempering, tag nrho cov khoom ntawm vuam seam tag nrho mus txog qib ntawm cov yeeb nkab lub cev, paub lub uniformity ntawm vuam seam thiab cov yeeb nkab lub cev kev ua tau zoo. Lub hauv paus ntawm qhov kev kho cua sov thev naus laus zis no yog los ua tus tswv ntawm cov tshuab hluav taws xob sib nqus sib nqus cua sov kom ntseeg tau tias qhov sib xws thiab qhov tseeb ntawm cov cua sov. Rau cov hlau tsis tshua muaj zog hlau thiab micro-synthesized high-strength steel welds, quenching cua sov kub yog 900 ~ 950 ℃, tempering cua sov yog 600 ~ 650 ° C, lub quenching adopts txau txias, thiab tempering txais cua cua txias thiab dej txias. Ua kom txias. Thaum lub quenching thiab tempering kub yog rhuab los ntawm ib tug longitudinal magnetic teb, qhov tseeb ntawm kev tswj kub tuaj yeem ncav cuag ± 10 ° C, uas yog qhov tsim nyog kub tswj theem rau high-strength welded kav kom ruaj khov kev ua tau zoo. Siv cov transverse teb cua sov welds kuj yuav tsum tau high precision kub tswj • tam sim no • Tuam Tshoj tseem nyob rau hauv txoj kev loj hlob theem, los ntawm qhov tseeb ntawm no loj sib txawv. Txawm li cas los xij, nws ntseeg tau tias lub tshuab cua sov no yuav dhau los sai sai, thiab cov vuam seam yuav sov thiab tempered los ntawm on-line induction cua sov.