1. The action cannot start according to the set procedure
The direct cause of this problem is that the reversing valve does not open normally.
Possible influencing factors include: valve core stuck in reversing valve; The ejector rod of the reversing valve is bent; Electromagnet of reversing valve burns out; Loose wires; The control relay fails, so that the electrical signal cannot be normally transmitted, and other reasons in the circuit cause the electrical signal to be interrupted; Improper operation, some switches and buttons are not in the correct position will cut off the control signal; In series in the same way in the throttle valve, speed control valve stuck, can not achieve normal action, any place in the oil channel accident blockage, the actuator can not start normally; Due to various reasons, the hydraulic power source cannot be transferred from the discharge state to the working state, nor can it normally push the actuator to move; When the load part fails, it is occasionally impossible to push it.
2. The action cannot end according to the set procedure
This kind of problem is generally caused by the reversing valve can not be closed in time, the possible reasons are: the reversing valve stuck, the valve core can not reset, this kind of problem is mostly related to oil pollution; The reversing valve spring is broken, the valve core cannot be reset; The drive electrical signal of the reversing valve fails to disappear in time (such as fault of travel switch, fault of time relay, fault of intermediate relay, control error, etc.).
In addition, load anomalies can cause the executable to fail to close normally.
3. Unexpected movements
This kind of problem is mainly caused by the fault of the reversing valve and the fault of the electrical signal.
The spool of the reversing valve is installed backward. If the two position of the reversing valve to open and close, there will be no power will have the phenomenon of action.
Due to the circuit failure, the electromagnet got the wrong electrical signal, causing the wrong action.
Reversing valve internal wear, pressure oil can through from its niche, into the hydraulic cylinder's two cavity, if is single rod hydraulic cylinder, the piston stress on both sides of the area, but the two cavities are equal, the oil pressure so the piston of hydraulic cylinder is a force toward the rod chamber, and slow moving in this direction.
