The selection of seals depends on the actual situation. Different working pressures, temperatures, media, motion forms, and speeds determine the different types of seals. For example, O-rings are suitable for sealing in static and rotating motions; Y-rings have good wear resistance and are suitable for reciprocating motion seals, etc. When receiving seals, it is important to carefully check the manufacturing date, deformation, aging, and whether the dimensions are qualified. If there are issues, they should not be used.

When installing sealing rings, care must be taken to avoid being scratched by burrs on sharp edges such as splines and threads, as this can cause oil leaks. Special caution is required during maintenance and assembly work. When the sealing ring must pass through openings such as keyways or threads on the shaft, a guiding tool should be used, and metal tools like screwdrivers should not be used for assembly, as they can scratch the sealing ring and cause distortion. Attention should also be paid to the correct orientation during assembly; if a directional sealing ring lip is installed incorrectly, it will not seal properly and may cause oil leaks. Improper force during installation can also lead to oil leaks. For example, when installing an O-ring, do not stretch it to a permanently deformed position, and do not roll it while installing, as this may cause twisting of the sealing ring and result in oil leaks.

The hydraulic system sequence valve uses the pressure of hydraulic oil as a control signal to control the opening and closing of various oil paths, thereby controlling the sequential operation of various components in the hydraulic system.

According to the source of hydraulic oil pressure, hydraulic system sequence valves can be divided into internal control and external control. Internal control is based on the pressure of hydraulic oil entering through the inlet, while external control is based on the pressure of hydraulic oil exiting through the outlet.

From a structural perspective, hydraulic system sequence valves can be divided into pilot-operated and direct-acting types. Pilot-operated valves are often used in ultra-high pressure hydraulic systems, while direct-acting valves are more commonly used in low-pressure systems.

In terms of oil leakage methods, hydraulic system sequence valves can be classified into internal leakage and external leakage. External leakage does not mean discharging hydraulic oil; it refers to discharging it into the oil tank through a separate pipeline, while internal leakage can directly discharge to the oil tank from the outlet.

In daily maintenance, the oil level in the tank should be kept at the required height to ensure sufficient cooling conditions for the oil. The water level in the cooler should be adequate, and the pipelines should be unobstructed to fully utilize the cooling effect of the cooler on the oil. Additionally, selecting hydraulic oil with the appropriate viscosity is also very necessary. If the viscosity is too high, energy loss during oil flow increases; if the viscosity is too low, leakage will increase, both of which can raise the oil temperature.