1.Raws li US cov cai, kev kho cua sov dab tsi yuav tsum tau ua rau txias -bent ERW carbon steel piping?
Rautxias khoovCov pa roj carbon steel piping (xws li ERW), US maritime kev cai (46 CFR 56.80-15) qhia tias cov yeeb nkab nrog phab ntsa tuab ntawmNtau dua lossis sib npaug li 0.75 ntixav tau ibkev nyuaj siab-relieving tshav kub khotom qab khoov. Qhov no yog txhawm rau txo cov kev ntxhov siab uas seem thiab muaj peev xwm hardening qhia los ntawm qhov txias -kev ua haujlwm-7.
2.Yuav ua li cas cov teeb meem hauv zos xws li dents lossis gouges cuam tshuam nrog ERW seam kom ceev tsis ua hauj lwm nyob rau hauv cyclic loading?
Cov kev tsis xws luag xws li dents tsim cov kev ntxhov siab hauv zos thiab ua rau tsis yog -ib puag ncig, sab hauv kinking deformation hom nyob rau hauv cyclic dabtsi yog khoov-10. Yog tias qhov teeb meem zoo li no nyob ntawm lossis ze ntawm ERW seam, cov kab mob cyclic yog concentrated nyob rau hauv ib cheeb tsam uas twb muaj lawm.txo toughness thiab residual kev nyuaj siab. Qhov kev sib koom ua ke no nce siab ntxivratcheting tus nqi(sau ntawm cov yas lim) thiab tuaj yeem ua rau qaug zog ntxov ntxov.
3.Dab tsi yog qhov kev sib tw vuam loj tshwj xeeb rau thaj chaw girth vuam ntawm siab -lub zog ERW kav zoo li X80?
Ib qho kev sib tw tseem ceeb yogtswj qhov tawg hauv cov yeeb nkab lub cev muaj zog. Siab -lub zog steels zoo li X80 muaj qhov kev txiav txim siab tsawg kawg nkaus lub zog (piv txwv li, 80 ksi), tab sis qhov tseeb tawm los tuaj yeem siab dua. Qhov kev hloov pauv no tuaj yeem ua rautsis xav txog lub zog tsis sib haumnrog cov hlau weld, cuam tshuam rau weld tsim nyog thiab muaj peev xwm ua rau strain concentration nyob rau hauv HAZ thaum lub sij hawm pipeline kev sib hais los yog hauv av txav-2.
4.Rau tuab - phab ntsa ERW yeeb nkab, dab tsi puv - kev kho lub cev yuav siv tau los ntawm cov seam annealing hauv zos?
Rau ERW cov kav dej uas muaj phab ntsa hnyav heev lossis cov uas tau txheeb xyuas tias khaws cov kev ntxhov siab ntau dhau (xws li pyramid-cov yeeb nkab dov), apuv -lub cev kev ntxhov siab kho cua sovtej zaum yuav siv tau. Qhov no suav nrog cua sov tag nrho cov yeeb nkab rau620-675 ° F (1148-1247 ° F)rau ib lub sij hawm teev tseg (xws li, 1 teev ib nti ntawm phab ntsa tuab) kom uniformly txo cov residual stresses thiab rov qab puas toughness-1.
5.Cov khoom siv ntawm cov yeeb nkab ERW (xws li, xws li -welded vs. heat-kho) cuam tshuam nws qhov tsim nyog rau kev pabcuam qaub raws li NACE cov qauv?
Qhov no yog qhov kev sib txawv tseem ceeb."Raws li-welded" ERW yeeb nkabfeem ntau yogtsis taurau kev pabcuam qaub hnyav vim tias qhov vuam thiab HAZ hardness yuav dhau NACE txwv. Nws yuav tsum tau txais atxheej txheem kev kho cua sov tsim nyog(normalizing los yog quenching thiab tempering) kom ua tiav ib qho zoo, mos microstructure thoob plaws weld-1. Cov yeeb nkab zeb yuav tsum muab cov ntaub ntawv qhia txog qhov nyuaj (piv txwv li, HAZ hardness < 248 HV) los lees paub ua raws.
