Raws li kev xaiv tswj kev ua haujlwm, ntau hom li qub muaj lawv tus kheej lub luag haujlwm, thiab yuav tsum tau them sai sai rau lawv cov haujlwm sib xws thaum xaiv lawv; Raws li kev xaiv ntawm kev ua haujlwm, cov txheej txheem tsis zoo ntawm cov khoom siv feem ntau suav nrog kev ua haujlwm siab, siab tshaj plaws kev ua haujlwm siab, ua haujlwm kub (tsawg kawg thiab siab tshaj qhov kub) thiab nruab nrab (corrosive, flammable), thaum xaiv, nws yuav tsum tau muab sau tseg tias saum toj no tsis ua hauj lwm tej yam kev mob yog raws li cov technical parameters ntawm lub valve; xaiv raws li tus qauv installation. Cov qauv kev teeb tsa ntawm cov kav dej muaj xws li cov yeeb nkab xov, flanges, ferrules, vuam, hoses, thiab lwm yam. Yog li ntawd, cov qauv kev teeb tsa ntawm lub valve yuav tsum ua raws li cov qauv kev teeb tsa ntawm cov kav dej, thiab cov kev qhia tshwj xeeb thiab qhov ntev yuav tsum zoo ib yam.
