①Pressure compensation tank.

Excessive pressure of the fluid being sealed or hydraulic shock can cause O-rings to leak. During dynamic sealing, if the pressure exceeds 4MPa, oil may leak. After installing the retaining ring, the pressure can be increased. However, the hydraulic shock will make the local instantaneous pressure several times higher than the normal working pressure, which may cause the O-ring to lose its sealing performance. In this case, grooves with pressure compensation can be used. With this groove, no leakage can be achieved even under the pressure of 16MPa. The groove size of this O-ring seal is as follows: the groove width b is 0.2~1mm larger than the wire diameter d1 of the O-ring, and the groove bottom diameter D is 0.2~2mm smaller than the inner diameter of the O-ring. Drill 2~4 holes at one end For a small hole with a diameter of 2~4mm, a single-acting hydraulic cylinder can be punched at one end, and a double-acting hydraulic cylinder can be punched at both ends (Figure 4-1). The gap between the outer diameter of the piston and the diameter of the cylinder can be increased. The larger the cross-sectional diameter of the O-ring, the larger the gap, generally 0.1~0.5mm. The usual sealing contact point is at the outside diameter (point a). At the sealing contact point between point a and one side (point c), as the pressure increases, the contact becomes tighter, which plays the role of pressure compensation, and there is no higher requirement for the dimensional tolerance of the piston processing, and the surface roughness R6.3~3.2um is enough.

② When rotating the seal, the O-ring can be placed obliquely.

When O-Ring Seals Manufacturers are used for rotary seals, the line speed should not be too high, generally 0.3~0.5m/s is suitable, otherwise oil will leak. When the O-ring is used for rotary sealing, frictional heat is generated at the contact point, the temperature continues to rise, and the oil breakage phenomenon occurs at the contact point, resulting in wear and aging. And rubber in stretched state shrinks when heated (Joule effect). That is to say, repeated cycles of "frictional heat, shrinkage, increased tightening force, friction..." greatly intensifies the aging, cracking and wear of the rubber, leading to seal failure, which is related to the amount of leakage and the speed of rotation. The inner diameter of the O-ring is designed to be equal to or slightly larger than the shaft diameter (3~5%). During installation (the ring is compressed from the outside to the inside, and the compression of the section is also designed to be smaller (about 5%). In addition, try to use heat-resistant materials, and consider the lubrication of the heat-dissipating O-ring to install the O-ring obliquely (Figure 4-2 ), after taking these measures, the pu value (sealing pressure 6 linear velocity) can reach 5.6MPa*7.65m/s=42.84MPa.m/s.