O-ring seals are made of nitrile rubber, silicone, and fluorinated rubber. They are used for dynamic sealing of hydraulic and pneumatic components (piston seals, piston rod seals) and static seals (axial seals). It is the most widely used seal in hydraulic engineering (only for low-speed rotary seals).
O-rings are O-section sealing rings that are mounted in grooves and have a moderate amount of compression. O-rings are vulcanized in a mold, the size of which is commonly defined by its internal diameter and cross-sectional diameter.
O-rings have many advantages over other sealing elements:
1, the structure is small, easy assembly and disassembly.
2, cheap, small size.
3, a large number of standard sizes available in the global spot, easy maintenance and repair.
The main content of the O-ring seal design is the compression ratio and elongation of the cross-sectional diameter, which is of great significance to the sealing performance and service life. For a good sealing effect of an O-ring, a reasonable amount of compression and elongation of the seal must be formed, and the correct matching of the O-ring size to the groove size becomes an important factor. When the sealing device is designed and processed, if the compression of the O-ring is too large, the O-ring rubber will cause stress relaxation and cause leakage; if the compression amount is too small, it will cause leakage. Similarly, over-stretching of O-rings can accelerate aging and cause leakage. All countries in the world have stricter standards.