Hauv kev tsim cov yeeb nkab, yuav tsum ua raws li ntau yam qauv thiab cov lus qhia kom ntseeg tau tias qhov zoo thiab kev nyab xeeb ntawm cov khoom kawg.ASTM A139yog ib qho qauv zoo li no uas ua lub luag haujlwm tseem ceeb hauv kev tsim cov kav hlau rau ntau yam kev siv.
ASTM A139 yog tus qauv txheem rau electrofusion (arc) welded steel yeeb nkab (NPS 4 thiab siab dua). Nws npog cov kev cai rau spiral seam electrofusion (arc) welded, nyias phab ntsa, austenitic steel yeeb nkab rau corrosive lossis kub siab. Tus qauv no piav qhia txog cov kev cai rau cov ntaub ntawv, cov txheej txheem tsim khoom, qhov loj me thiab cov khoom siv kho tshuab ntawm cov yeeb nkab hlau.
Cov khoom siv uas yuav tsum tau ua ntawm ASTM A139 qhia meej txog cov hom thiab qib ntawm cov hlau uas siv tau los ua cov kav dej. Qhov no suav nrog cov tshuaj lom neeg ntawm cov hlau, uas yuav tsum muaj cov feem pua tshwj xeeb ntawm cov ntsiab lus xws li carbon, manganese, phosphorus, sulfur thiab silicon. Cov kev cai no yog qhov tseem ceeb rau kev ua kom ntseeg tau tias cov hlau siv rau hauvcov kav dejua tau raws li cov qauv tsim nyog ntawm lub zog thiab kev tiv thaiv corrosion.
Cov txheej txheem tsim khoom rau ASTM A139 yeeb nkab suav nrog electrofusion (arc) vuam, uas siv hluav taws xob arc los tsim cov cua sov uas xav tau los vuam cov hlau ua ib lub cylindrical. Cov txheej txheem no raug tswj hwm kom zoo kom ntseeg tau tias cov vuam zoo thiab tsis muaj qhov tsis zoo. Tus qauv kuj tseem qhia txog cov txheej txheem tshuaj xyuas rau cov vuam, xws li kev sim ultrasonic thiab kev sim khoov transversely, kom ntseeg tau tias lawv ua tau raws li cov qauv zoo uas xav tau.
Hais txog qhov ntev, ASTM A139 qhia txog cov kev cai rau qhov loj ntawm cov yeeb nkab, phab ntsa tuab, thiab ntev. Qhov no suav nrog kev kam rau siab tshwj xeeb ntawm qhov ntev kom ntseeg tau tias cov yeeb nkab ua tau raws li cov lus qhia tsim nyog rau nws siv. Cov kev cai ntawm qhov ntev no yog qhov tseem ceeb rau kev ua kom cov yeeb nkab tau teeb tsa thiab txuas nrog kom raug hauv ntau yam kev siv.
Cov khoom siv kho tshuab xws li lub zog tensile, lub zog yield, thiab elongation kuj tau teev tseg hauv ASTM A139. Cov khoom no yog qhov tseem ceeb hauv kev txiav txim siab lub zog thiab kev ua tau zoo ntawm cov yeeb nkab hauv ntau yam kev ua haujlwm. Tus qauv teeb tsa cov kev cai tsawg kawg nkaus rau cov khoom siv kho tshuab no kom ntseeg tau tias cov yeeb nkab tuaj yeem tiv taus qhov siab, kub thiab cov xwm txheej ib puag ncig.
Zuag qhia tag nrho, ASTM A139 ua lub luag haujlwm tseem ceeb hauv kev tsim khoom ntawmcov kav hlaurau ntau yam kev siv. Los ntawm kev teev cov ntaub ntawv, cov txheej txheem tsim khoom, qhov loj me thiab cov khoom siv kho tshuab ntawm cov kav dej, tus qauv no ua kom ntseeg tau tias cov khoom kawg ua tau raws li cov qauv zoo thiab kev nyab xeeb tsim nyog. Nws muab kev ntseeg siab rau cov chaw tsim khoom, cov kws ua haujlwm thiab cov neeg siv kawg tias cov kav dej yuav ua haujlwm raws li qhov xav tau hauv nws daim ntawv thov.
Hauv kev xaus lus, kev nkag siab txog qhov tseem ceeb ntawm ASTM A139 hauv kev tsim cov yeeb nkab yog qhov tseem ceeb rau kev ua kom zoo thiab kev nyab xeeb ntawm cov khoom yeeb nkab hlau. Tus qauv teeb tsa cov kev cai tsim nyog rau cov ntaub ntawv, cov txheej txheem tsim khoom, qhov loj me thiab cov khoom siv kho tshuab kom ntseeg tau tias cov yeeb nkab ua tau raws li cov qauv zoo thiab kev ua tau zoo. Los ntawm kev ua raws li ASTM A139, cov chaw tsim khoom tuaj yeem tsim cov yeeb nkab hlau zoo uas ua tau raws li qhov xav tau ntawm ntau yam kev lag luam thiab kev siv.
Lub sijhawm tshaj tawm: Lub Kaum Ob Hlis-28-2023