Polyurethane sealing ring has the characteristics of wear resistance, oil, acid and alkali, ozone, aging, low temperature, tearing, impact, etc. The polyurethane sealing ring has a large load support capacity and is widely used in various fields. Casting type sealing ring is resistant to oil, hydrolysis, abrasion and high strength, suitable for high pressure oil equipment, lifting equipment, forging machine tools, large hydraulic equipment, etc.
Polyurethane sealing ring is also called a seal or an oil seal. It is an annular cover composed of one or several parts, fixed on a ferrule of a shaft or a bearing, and contacts with another ferrule or washer or forms a narrow labyrinth gap to isolate The function of oil and gas prevents oil from overflowing or passing through and foreign objects from intruding. At the same time, it can also bear pressure, and has the dual functions of pressure bearing and sealing within a certain range.
1. The sealing ring should have good sealing performance within the working pressure and a certain temperature range, and can automatically improve the sealing performance as the pressure increases.
2. The friction force between the sealing ring device and the moving parts should be small, and the friction coefficient should be stable.
3. The sealing ring has strong corrosion resistance, is not easy to age, has a long working life, good wear resistance, and can automatically compensate to a certain extent after wear.
4. The structure is simple, easy to use and maintain, so that the sealing ring has a longer life.
Application of polyurethane sealing ring
1. Used for sealing pistons in reciprocating hydraulic cylinders.
2. It is an axial sealing ring used to prevent internal grease or oil from leaking out, and also to prevent the intrusion of splashing water or dust from the outside.
3. Used in construction machinery to manufacture reciprocating seal rings in hydraulic systems,
4. Static and reciprocating seals for rotary motion.
5. Protective seals for hydraulic oils, emulsions, water mixtures
6. Sealing rings for hydraulic and pneumatic systems in liquid and gas working media such as air, water, oil, etc.
7. Used for oil cylinders, mechanical cylinder piston rods or valve stem dust-proof seals under severe working conditions from -40°C to +120°C
8. It is used as a retaining ring for sealing rings when the working temperature is -100℃～+200℃ and the cylinder pressure is greater than 10MPa.
9. Used for the sealing of pipelines in various processes such as petroleum, chemical industry, metallurgy, papermaking, sewage, seawater desalination, food brewing and beverage processing, medicine, etc.
In addition to the general requirements of the polyurethane sealing ring material, the sealing ring should also pay attention to the following conditions: (1) high elasticity and resilience; (2) appropriate mechanical strength, including expansion strength, elongation and tear strength, etc. . (3) The performance is stable, it is not easy to swell in the medium, and the heat shrinkage effect (Joule effect) is small. (4) It is easy to process and shape, and can maintain precise dimensions. (5) Do not corrode the contact surface, do not pollute the medium, etc. The most suitable and commonly used material to meet the above requirements is rubber, so most sealing rings are made of rubber materials. There are many kinds of rubber, and new rubber varieties are constantly appearing. When designing and selecting, one should understand the characteristics of various rubbers and choose reasonably.
