Why the four-column hydraulic press action failure?

What is the cause of the failure of the four-column hydraulic press, slow speed without pressure first check whether the solenoid valve is normal, or the relief valve bypass valve is damaged, if so, it should be repaired or replaced in time, the system pressure reducing valve set value is too low, the pilot valve of the pressure reducing valve wear will make the valve work unstable, or even can not adjust the pressure. The second possibility is that the integrated channel block design is wrong, the pressure reducing valve is damaged, and another pump, motor or cylinder may be damaged and have large internal leakage. Working under long-term variable load, causing the spring to become soft, the spring length to shorten or the whole break, crack, spalling or other damage, which may make the valve fail, so that the system can not work normally, because the sealing ring of the three-beam and four-column hydraulic press will also wear in the process of long-term work, making the pressure leakage unstable. Improper operation during the installation process may also cause parts to deform, the piston rod and cylinder are stuck or the hydraulic cylinder is blocked, the hydraulic system control pressure is too low, the hydraulic system enters the air, the spool is stuck or the valve hole is blocked, the hydraulic oil viscosity is large, and the fluidity is poor, resulting in slow action of the hydraulic cylinder, which affects the pressure instability of the hydraulic press.