单项选择题
A.overflow valve B.reducing valve C.relief valve D.sequence valve
The symbol (GB786√1-93) at right side represents （）A.ov...
单项选择题The symbol (GB786√1-93) at right side represents （）
Overflow valve is used to （）A.control the fluid flow th...
单项选择题Overflow valve is used to （）
A.control the fluid flow through it B.prevent the pressure before it over the specified valve C.make the pressure after it steady D.control the direction of oil flow
Hydraulic control check value is generally used to （） i...
单项选择题Hydraulic control check value is generally used to （） in the marine hydraulic mechanism.
A.control the back pressure of return oil B.lock the oil lines under some conditions C.change the direction of oil flow D.act as relief valve
