- First, it is required that the leakage of hydraulic seals is extremely small, has a good sealing effect, and automatically improves its sealing effect as the pressure of hydraulic oil increases. Even in harsh working environments such as high pressure and high temperature, the leakage of hydraulic seals will also no significant increase;
- Second, because the hydraulic seal is immersed in the hydraulic oil for a long time, it is easy to swell, dissolve or become brittle and hard, so that it loses its sealing effect, so the hydraulic seal must have good compatibility with the hydraulic oil;
- Third, in order to avoid or reduce the undesirable phenomena such as low-pressure crawling of hydraulic equipment, hydraulic seals are required to have low static frictional resistance and dynamic frictional resistance, and their friction coefficient should be very stable.
- Fourth, hydraulic rubber seals should have good elasticity, heat resistance, cold resistance, pressure resistance, wear resistance and certain physical and mechanical strength, and have a good service life;
- Fifth, in addition to being easy to manufacture and install, the corresponding sealing groove is easy to manufacture, and the requirements for the machining accuracy of the sealing surface are low, the price of hydraulic rubber seals must also be low to meet the needs of users for a large number of long-term use;
- Sixth, the leakage of hydraulic rubber seals must be extremely small, and it has good sealing properties. Moreover, hydraulic rubber seals can automatically improve their sealing effect as the pressure of hydraulic oil increases, even in harsh working environments such as high pressure and high temperature. The leakage of hydraulic rubber seals cannot be significantly increased;
- In summary, the basic requirements for hydraulic seals are long service life, good compatibility, good sealing, safety and reliability, and strive to be compact in structure, simple in system, convenient in manufacturing and maintenance, and low in cost, especially for most seals. Parts are wearing parts, and should ensure interchangeability, standardization and serialization.