單項選擇題

A swing check valve is used in a pipeline to （）.

A.maintain a preset pressure on the line
B.closely regulate the amount of flow
C.relieve excessive pressure on the line
D.allow flow in one direction only

你可能感興趣的試題

單項選擇題

Sluggish response or action of the hydraulic actuators may be a result of （）.

A.insufficient load
B.excessively high oil viscosity
C.relief-valve pressure setting too high
D.reservoir level being maintained two inches above normal

單項選擇題

A knocking sound from one cylinder of an operating air compressor indicates （）.

A.a defective or broken high pressure un-loader
B.a loose valve plate
C.excessive overload
D.no compression

无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

A swing check valve is used in a pipeline to （）.

你可能感興趣的試題

Sluggish response or action of the hydraulic actuators may be a result of （）.

A knocking sound from one cylinder of an operating air compressor indicates （）.