The key is that the speed of the hydraulic press is stable and the piston is normal

The excellent performance of hydraulic presses, such as forging, stamping, cold extrusion, straightening, twisting, flanging, thin plate drawing, powder metallurgy, press-fitting and other process performances, make it very popular among users in the industry. Of course, there will also be some problems during the use of single-column hydraulic presses, such as unstable speed.
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In the hydraulic system of the hydraulic machine, when the three-position four-way reversing valve is in the neutral position, the oil path to the hydraulic cylinder is blocked, and the two chambers of the hydraulic cylinder are connected to each other and the oil path is returned. In this way, part of the oil flows back into the tank under the effect of potential energy. When the reversing valve changes direction, one chamber of the hydraulic cylinder passes pressure oil, and the other chamber lacks back pressure, causing the hydraulic cylinder to move forward and the initial speed is unstable.
Hydraulic presses in double-rod hydraulic cylinders will also have unstable speed due to the unequal leakage of the two chambers and the different frictional resistance of reciprocating motion. Imperfect design of the hydraulic system of the hydraulic press, mismatched component selection, sometimes blocked and sometimes unblocked saving channels, serious leakage inside and outside the system, excessive air entering the oil, changes in frictional resistance, etc. will also lead to unstable speed of the actuator at low speeds.
If it is found that the operating speed is unstable during the operation of the hydraulic press, it is necessary to check, troubleshoot, and maintain it in time to avoid adverse factors as much as possible and ensure the stable operation of the equipment. The piston is the main component of the hydraulic cylinder in the hydraulic press. If the piston fails, the hydraulic cylinder will also stop, and the operation of the hydraulic press will also be affected.
The piston of the hydraulic press works under conditions of high temperature, high pressure, high speed and poor lubrication. The piston is in direct contact with some high-temperature gases, and the temperature can reach more than 2500K in an instant. Therefore, if the heating is serious, the heat dissipation conditions are also very poor. Therefore, the temperature of the piston is very high when it is working, and the temperature distribution is also very uneven.
High pressure will also cause the impact of the piston of a single-column hydraulic machine to be very large, and it will also be affected by side pressure; the piston reciprocates in the cylinder at a very high speed, and the speed is not constant. Unchanged, this also generates a large inertia force, causing the piston to receive a large additional load. Therefore, the maintenance of the piston should also be paid attention to.