1. Q: Thaum vuam API 5L X70M PSL2 HFIW yeeb nkab rau daim ntawv thov kev pabcuam qaub, qhov kev txwv ntawm qib sulfur yog qhov tseem ceeb thiab vim li cas?
A:Rau kev pabcuam qaub (H₂S muaj), cov ntsiab lus sulfur yuav tsum qis heev, feem ntau Tsawg dua lossis sib npaug li 0.002% (lossis 20 ppm). Qhov no txo qis kev tsim ntawm manganese sulfide (MnS) suav nrog, uas tuaj yeem ua qhov chaw pib rau Hydrogen Induced Cracking (HIC) thiab Sulfide Stress Cracking (SSC).
2. Q: Dab tsi yog qhov tseem ceeb ntawm cov lus "M" hauv qib zoo li API 5L X65M?
A:Cov lus "M" sawv cev rau "Mandatory" thiab qhia tias cov yeeb nkab tau tsim los siv aCov txheej txheem thermomechanical tswj (TMCP). Cov txheej txheem niaj hnub no txhim kho lub zog thiab toughness yam tsis tau tso siab rau cov ntsiab lus carbon siab, txhim kho weldability.
3. Q: Rau ASTM A134 yeeb nkab (hluav taws xob- fusion- welded), dab tsi yog qhov tsawg kawg nkaus phab ntsa tuab nws tuaj yeem tsim rau, thiab dab tsi yog daim ntawv thov?
A:ASTM A134 cov kav dej feem ntau yog rau cov kab loj loj (tshaj 4 ntiv tes) thiab tuaj yeem muaj cov phab ntsa nyias nyias rau lawv qhov loj me (piv txwv li, 1/8 "min).
4. Q: Qhov twg ASTM tus qauv npog arc-welded steel yeeb nkab rau siab- qhov kub thiab txias, thiab npe ib qib sib npaug rau A106 Qib B.
A:ASTM A672 npog hluav taws xob- fusion-welded steel yeeb nkab rau siab- kev pabcuam siab ntawm qhov kub nruab nrab. Ib qib uas yogASTM A672 B70, uas yog piv rau A106 Qib B hauv tshuaj thiab cov khoom siv kho tshuab.
5. Q: Dab tsi ncej-weld kev kho cua sov (PWHT) yuav tsum tau rau ASTM A691 Qib 1¼ Cr yeeb nkab tom qab vuam?
A:ASTM A691 Cr-Mo alloy kav feem ntau xav tau PWHT tag nrho raws li txoj cai ntawm kev tsim kho (xws li ASME B31.3). Rau Qib 1¼ Cr (xws li 1.25Cr-0.5Mo), PWHT feem ntau ua nyob rau hauv thaj tsam ntawm 1250-1300℃F kom npau taws rau cov vuam thiab HAZ, txo cov kev ntxhov siab, thiab rov ua kom corrosion kuj.
