There are many types of rubber seal products and different working conditions, such as heat resistance, oil resistance, chemical corrosion resistance, working conditions (static, dynamic, rotating and swinging, etc.), speed, working pressure, etc. Therefore, the rubber seals used for mechanical seals should first consider the requirements of the use conditions or special conditions from the rubber, and then comprehensively consider the reasonable formula and rubber seals in the vulcanization acceleration system, the reinforcement filling system, the softening system, and the protection system. Processing technology. The rubber compound generally used for mechanical sealing should have good elasticity and low compression set to meet the special performance requirements of different products. As a dynamic seal, the rubber compound is also required to have certain tensile strength, good wear resistance, and tear resistance.

1. O-ring rubber compound

O-shaped sealing ring is a kind of sealing product with simple appearance and structure, various specifications and a large number of needs. The sealing quality life of O-rings depends on the dimensional accuracy and rubber material. Generally, the rubber material is required to have a certain degree of mechanical strength. The tear resistance of rubber seals, good heat resistance, oil resistance, chemical resistance, and small compression set under service conditions are the main indicators. According to the application requirements, there are generally heat and oil resistance requirements, and the most used rubber is nitrile rubber. Acrylic rubber can be used for oil-resistant sealing products that require higher temperatures (such as 150~C—l90°C). Fluorine rubber for oil-resistant rubber products that require higher temperatures, and silicone rubber for heat-resistant applications. In the filling and reinforcement system of heat-resistant and oil-resistant rubber formulations of O-rings, low-activity thermal black, spray carbon black or semi-reinforcing carbon black are often used. These carbon blacks are characterized by relatively coarse particles. , The rubber has good elasticity, low heat generation, low compression and permanent deformation, and can be filled in large quantities, reducing the cost of the rubber.

2. Oil seal compound

The oil seal is an important part of the media seal of the transmission shaft, and its quality and life are directly related to the normal operation of the machine. Oil seals are generally used under dynamic conditions and are in direct contact with the sealed medium such as oil. Therefore, oil seal compounds are required to have good oil resistance, wear resistance and a small coefficient of friction.

3. Rubber sealing strip

Rubber sealing strips are mainly used in various doors and windows of automobiles, airplanes, railways and high-rise buildings to prevent external dust, air, water, etc. from entering the system. Since most of the rubber seal materials are used in doors and windows of cars, trains, airplanes and high-rise buildings, rubber materials are required to have good weather resistance, aging resistance and good mechanical properties, suitable elongation, compression set and Cold resistance.