1) The oil does not enter the hydraulic cylinder.
1 The reversing valve is not reversing.
2 The system is not supplied with oil.
2) Although there is oil, there is no pressure.
1 The system is faulty, mainly because the pump or the relief valve is faulty.
2 The internal leakage is serious, the piston and the piston rod are loose, and the seal is seriously damaged.
3) The pressure does not reach the specified value.
1 The seal is aging and fails, and the seal lip is reversed or damaged.
2 Piston ring is damaged.
3 system setting pressure is too low.
4 The pressure regulating valve is faulty.
5 When the flow rate of the regulating valve is too small, when the leakage amount in the hydraulic cylinder increases, the flow rate is insufficient, resulting in insufficient pressure.