Kos valve yog tsim thiab tsim tag nrho raws li qhov yuav tsum tau muaj ntawm API 6A 《Cov Khoom Siv Khoom Siv rau Wellhead thiab Christmas Ntoo》, tuaj yeem siv sib hloov nrog cov khoom siv hauv tsev thiab txawv teb chaws uas yog inline nrog API 6A Standard. Cov tub ntxhais txais yuav sulfide-tsis kam hlau thiab tuaj yeem siv rau hauv H2S mob, lub cev valve ua los ntawm alloy steel forging nrog kev ua tau zoo. Ob hom Check li qub yog muab los ntawm landrill: Viav vias hom thiab Lift hom.