API 5L GR.BChitoliro chachitsulo chosasunthika ndi chinthu chomwe chimagwiritsidwa ntchito kwambiri mumakampani opanga mafuta ndi gasi, mogwirizana ndiAPI 5Lmuyezo wa American Petroleum Institute. Magiredi ofanana a zinthu pansi pa muyezo uwu akuphatikizapo mulingo wa PSL1GR.A, GR.B, GR.X42 kupita ku GR.X52, ndi PSL2 level GR.X56 mpaka GR.X80. Manambalawa akuyimira mphamvu yocheperako yopezera, yoyesedwa mu ksi. GR.B ndi chitsulo chapakati cha carbon-manganese chokhala ndi mphamvu yapakatikati yokhala ndi mphamvu zabwino kwambiri zamakaniko komanso kuthekera kolumikizana.
Kapangidwe ka mankhwala ka GR.B kamakhala ndi mpweya wochepa wosapitirira 0.28%, manganese wosapitirira 1.20%, komanso kuwongolera kwambiri zinthu zodetsa monga phosphorous ndi sulfure. Mphamvu yake yolimba si yochepera 414 MPa, mphamvu yake yotulutsa si yochepera 241 MPa, ndipo kutalika kwake si kochepera 21%. Imatha kukwaniritsa zofunikira zoyendera zapakati komanso zamphamvu. Njira yopangira mapaipi achitsulo opanda zingwe imawapangitsa kukhala ndi mphamvu yonyamula kupanikizika komanso kufanana, yoyenera malo okhala ndi kupanikizika kwakukulu. Kuphatikiza apo, zinthu za GR.B zimatha kusintha malo okhala ndi kutentha kochepa kudzera mu mayeso ena owonjezera ndikuwonjezera kukana dzimbiri kudzera mu zophimba zotsutsana ndi dzimbiri.
Mapaipi achitsulo chosasunthika a API 5L GR.B amagwiritsidwa ntchito makamaka poyendetsa mafuta ndi gasi, kuphatikizapo mapaipi amtunda ndi a m'mphepete mwa nyanja, zida zogwirira ntchito, ndi mapaipi obowola. Kuphatikiza apo, amagwiritsidwanso ntchito mumakampani opanga mankhwala ponyamula zinthu zowononga, mu mphamvu ndi mphamvu zamapaipi a boiler okhala ndi mphamvu zambiri, m'maukonde operekera gasi ndi madzi mumzinda, komanso m'magawo omwe akutuluka monga mphamvu ya haidrojeni ndi kugwidwa kwa kaboni. Poyerekeza ndi chitsulo wamba cha kaboni, GR.B ili ndi mphamvu zambiri komanso kukana kupanikizika, ndipo poyerekeza ndi chitsulo chosapanga dzimbiri, ndi yotsika mtengo kwambiri ndipo ndi yoyenera mapulojekiti akuluakulu a mapaipi.
Posankha mapaipi achitsulo a API 5L GR.B, zinthu monga kuyanjana kwapakati, kutentha kogwirira ntchito, ndi zofunikira zotsutsana ndi dzimbiri ziyenera kuganiziridwa. Pa malo apadera monga acidity kapena kutentha kochepa, zipangizo za PSL2 zapamwamba kapena mayeso owonjezera ziyenera kuvomerezedwa. Zipangizozi, zomwe zimagwira ntchito bwino komanso mitundu yosiyanasiyana ya ntchito, zakhala chisankho chabwino kwambiri chonyamulira mapaipi amphamvu kwambiri mtunda wautali.