1. The reason for leakage: the cylinder and the piston are too large due to wear and tear. If the piston is fitted with a sealing ring, the sealing effect is lost due to wear or aging of the sealing ring.
2, the method of eradication: exchange piston or seal ring, adhere to a reasonable open space.
3. If the cylinders are often used only by some, some wear is serious, the open space increases, and the cylinder leaks. At this time, the cylinder diameter can be reground and the piston can be reconfigured.
The internal pressure of the hydraulic cylinder is not strong, and the movement resistance is too large, so that the speed of the cylinder changes with the direction of the stroke.
The reason for the appearance of this appearance: due to poor quality of the device. (The piston rod seal is pressed too tightly, the piston rod is long, and the pressure is excessively applied at the sliding part) or the dirt enters the sliding part of the cylinder (especially granular dirt)
If the overflow valve enters the waste, the spool is normally open, the oil automatically flows back to the tank, and no oil flows into the cylinder of the hydraulic press.
If the load is too large, the adjustment pressure of the relief valve has reached the maximum rated value, but the cylinder still does not have the force required for continuous action, and the cylinder does not operate. If the adjustment pressure is low and the thrust required for the load is not reached, the performance pressure is lacking and the thrust is not available. These questions are all on the hydraulic pressure relief valve, so the relief valve should be checked.
There is air or oil pump in the cylinder for lack of oil, which will make the cylinder unstable (or slow).
Elimination: Clean the air in the hydraulic cylinder or check the oil pump.
There is also a case where the pressure in the cylinder flashing from the pressure gauge is satisfactory, but the cylinder still does not move.
The reason for this appearance is that the surrounding surface of the piston is in tight contact with the cylinder head, the pressure oil can not enter or the useful working area of the hydraulic press is too small, and the satisfactory thrust can not be caused to make the cylinder move.