A unloading circuit composed of three-position four-way directional control valve requires that the two chambers of the hydraulic cylinder are blocked when the hydraulic cylinder stops. What type of center function of the directional valve should be selected ? ()
A. “M”
B. “Y”
C. “P”
D. “O”
查看答案
What does the numbers in 4/2 valve mean?
A. 4 positions and 2 ways
B. 4 ways and 2 positions
C. none of the above
Check valve is a type of
A. pressure reducing valve
B. pressure relief valve
C. directional control valve
D. none of the above
How is reverse flow possible in pilot operated check valve?
A. spring force lifts the ball due to which reverse flow is possible
B. fluid pressure lifts the ball due to which reverse flow is possible
C. both a and b
D. none of the above
A pressure relief valve can be
A. direct operated
B. pilot operated
C. solenoid operated
D. all the above
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