Ma valve owunika, ma valve osabwerera, adapangidwa kuti aletse kusinthika kwa kayendedwe ka mapaipi.Ma valve awa amayendetsedwa ndi zinthu zomwe zikuyenda mu payipi.Kuthamanga kwa madzi omwe akudutsa mu dongosolo kumatsegula valavu, pamene kutembenuka kulikonse kudzatseka valve.

API602 chekeni vavu  ndi ang'onoang'ono ang'onoang'ono owunika ma valve, omwe amapangidwa ndi chitsulo chonyezimira.we nthawi zambiri timawapanga mu swing check valve, piston check valve (lift check valve).Amapezeka m'mapangidwe atatu a bonnet.Mapangidwe oyamba ndi Bolted Bonnet, yokhala ndi cholumikizira chachimuna ndi chachikazi, chopangidwa ndi F316L/graphite.mphete olowa gasket ziliponso pa pempho.Mapangidwe achiwiri ndi boneti wowotcherera, wokhala ndi ulusi wowotcherera komanso wosindikizira.