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.