單項(xiàng)選擇題

An orifice-check valve placed in a hydraulic system is used to（）

A.regulate the fluid flow in either direction
B.restrict movement of hydraulic fluid in one direction, but allow free movement in the other direction
C.allow free movement of hydraulic fluid in both directions
D.allow a restricted fluid flow in one direction only

你可能感興趣的試題

單項(xiàng)選擇題

Purging air from a hydraulic system is necessary when（）

A.adding small amounts of oil to the system
B.the system has been overheated
C.the system has been drained and then filled with new oil
D.the system has been idle for a long period of time

單項(xiàng)選擇題

Leakage of hydraulic fluid from around the shaft of a hydraulic motor may be caused by（）

A.permanent loss of pump suction
B.worn shaft seals
C.high level in the oil sump
D.low motor RPM