Lift check valve with a spring load can withstand light valve flap, flap valvelift is not high.
升降式止回阀使用一个可承受弹簧载荷的轻量阀瓣，阀瓣的升程不高。
2
According to this problem, casing oil stolen prevention sealing valve was developed, matching with down-hole oil-gas separator and gas liftvalvelift technology.
针对这一难题，研制了套管防盗油密封阀，并配套应用了井下油气分离器与气举阀助流举升工艺技术。
3
The formula of wax and PTC heating plates at different Curie points are the main factors influencing the enriching valvelift.