1. Dab tsi yog thawj daim ntawv thov thiab cov peev txheej ntawm ASTM A139 steel yeeb nkab?
Teb:ASTM A139 yog ib qho kev qhia tshwj xeeb rauhluav taws xob-fusion (arc)-welded steel yeeb nkabhauv qhov ntau thiab tsawg NPS 4 thiab siab dua. Nws thawj daim ntawv thov yog raupipeline kis tau tus mobrau dej, roj, roj, thiab lwm yam dej. Nws feem ntau yog siv rau hauv cov kav dej hauv nroog, cov kav dej phwj tuaj, thiab cov txheej txheem kev lag luam piping qhov twg siab - yuav tsum muaj peev xwm. Cov txheej txheem npog cov kav dej uas tsim nyog rau kev khoov teb, muab kev kho kom haum raws li txoj cai.
2. Cov txheej txheem tsim khoom ntawm A139 yeeb nkab cuam tshuam nws cov khoom li cas?
Teb:A139 cov kav dej yog tsim los siv covHluav taws xob tsis kam vuam (ERW)los yoghluav taws xob fusion weldtxheej txheem. Qhov no suav nrog kev tsim cov yeeb nkab los ntawm coiled steel phaj thiab vuam cov seam yam tsis muaj qhov sib ntxiv ntawm cov hlau muab tub lim. Cov txheej txheem txuas ntxiv no tso cai rau cov khoom siv siab thiab cov yeeb nkab ntev ntev, uas tuaj yeem txo cov nqi installation. Txawm li cas los xij, weld seam yog qhov chaw tseem ceeb. Nws yuav tsum tau tswj xyuas nruj me ntsis thiab feem ntau raug sim tsis yog- puas tsuaj kom ntseeg tau tias nws tsis muaj qhov tsis xws luag uas tuaj yeem dhau los ua cov ntsiab lus tsis ua haujlwm nyob rau hauv siab.
3. Dab tsi yog cov cuab yeej tseem ceeb los kuaj xyuas cov yeeb nkab A139, thiab lawv tau sim li cas?
Teb:Ob qho tseem ceeb mechanical zog yogTensile zogthiabYield zog.
Tensile zog:Yam tsawg kawg nkaus 48,000 psi (Qib A) lossis 60,000 psi (Qib B).
Yield zog:Yam tsawg kawg 30,000 psi (Qib A) lossis 35,000 psi (Qib B).
Cov no raug txheeb xyuas los ntawmkev kuaj puas tsuajua rau cov qauv txiav los ntawm cov kav dej ntau lawm. Kev ntsuam xyuas yog ua rau txhua qhov ntau ntawm 400 kav dej lossis tsawg dua. Qhov kev sim no suav nrog kev ncab ib daim coupon qauv hauv lub tshuab ntsuas tensile kom txog thaum nws tawg los ntsuas lub zog nws tuaj yeem tiv taus.
4. Puas yog post-weld heat treatment (PWHT) rau A139 kav?
Teb:Tsis yog, tom qab -weld heat treatment yogtsis yog qhov yuav tsum tau uaRaws li ASTM A139 tus qauv. Cov yeeb nkab feem ntau yog siv los ua -welded condition. Txawm li cas los xij, tus specifier (piv txwv li, tus kws ua haujlwm ua haujlwm) yuav xav tau kev ua haujlwm zoo lossis kev ntxhov siab-cov yeeb nkab tso siab rau cov ntawv thov tshwj xeeb uas cuam tshuam nrog qhov txias txias, qis- kev pabcuam kub, lossis txhawm rau txhim kho qhov ruaj khov thiab txo qhov kev ntxhov siab ntawm cov txheej txheem vuam. Qhov no yuav yog ib qho kev xav tau ntxiv uas tau teev tseg hauv daim ntawv xaj yuav khoom.
5. Dab tsi yog cov qauv ntsuas hydrostatic rau cov yeeb nkab A139?
Teb:Txhua qhov ntev ntawm A139 yeeb nkab yuav tsum tau txais atsis yog -kev puas tsuaj hydrostatic test. Kev ntsuas siab yog xam los ntawm kev siv cov mis tshwj xeeb uas tau muab hauv tus qauv:P=2St / D, qhov twg:
P=Qhov ntsuas qhov tsawg kawg nkaus (psi)
S=Tso cai Fiber Stress, uas yog 50% ntawm qhov tsawg kawg nkaus yield zog (psi)
t=Nominal Phab Ntsa Thickness (hauv)
D=Nominal Outside Diameter (hauv)
Qhov kev ntsuam xyuas no txheeb xyuas lub suab ntawm cov yeeb nkab lub cev thiab cov vuam seam los ntawm kev ua rau nws lub siab ntau dua li qhov nws xav tau kev khiav hauj lwm siab, kom ntseeg tau tias nws tuaj yeem ua tau zoo hauv kev pabcuam.
