O-ring and lip seal:

• Compared with the O-shaped sealing ring, the main disadvantage of the lip type sealing ring is that it can only be used as a one-way seal. If it is used as a two-way seal, two sealing rings are required, which will increase the length of the seal; the groove design is difficult. Moreover, oil traps between the two sealing rings will cause back pressure damage; and the cross-sectional shape of the extruded sealing ring is symmetrical, which can be used as a two-way seal, with a small volume and easy groove design.

The advantages and disadvantages of O-rings and Y-shaped seals and their uses:

• Advantages of O-shaped sealing ring:

1. The sealing ring has a small cross-sectional size, and the installation groove can be designed as an integral groove;

2. The groove processing and sealing ring are easy to install, and it can be sealed in two directions (for double pressure).

• Advantages of Y-shaped sealing ring:

1. Good sealing

2. The friction is small at low pressure;

3. It can be automatically compensated after a small amount of wear and has a long service life;

• Disadvantages of O-shaped sealing ring:

1. Poor sealing

2. It is prone to roll, twist, and cause damage when the friction is large when the pressure is low;

3. The friction margin is reduced, which directly affects the sealing performance.

• Disadvantages of Y-shaped sealing ring:

1. It works in one direction. A pair of sealing rings is required when sealing two-way fluids, the sealing structure is complicated and the size is large;

2. There may be trapped oil between the two sealing rings, causing back pressure damage;

3. The sealing ring has a large cross-sectional size, which requires a split installation groove, which makes groove processing complicated;

• The main purpose of O-ring seal:

1. Small size slide valve;

2. Live races and piston rod seals that allow a small amount of leakage;

• The main purpose of Y-shaped sealing ring:

1. It is suitable for the sealing of pistons and piston rods that require higher comprehensive sealing performance;

Based on the above comparison, in the case of allowing a small amount of leakage, the squeeze-type sealing ring can reduce the groove size; and in the case of high sealing performance requirements, a lip-shaped sealing ring with better comprehensive performance should be used.