单项选择题
A.Overflow valve B.Reducing valve C.Balancing valve D.Reducing valve or balancing 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 （）
A.overflow valve B.reducing valve C.relief valve D.sequence valve
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
