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Rubber and plastic materials as seals, often rely on the interference of these materials to achieve seal, and this interference in hydraulic and pneumatic seals (such as tie rod seal, piston seal) will be worn, it is a key factor leading to the failure of seals and determine the service life of seals. The extent of this wear depends not only on the radial pressure the rubber is subjected to (as a result of the interference of the seal and the fluid pressure), but also on the coefficient of friction of these sealing materials.

The wear of seals under the same radial pressure depends mainly on the friction coefficient of sealing materials. The friction coefficient is small, the friction heat generation effect is small, the wear amount is small, the service life of the seal is long; And vice versa. Because the friction coefficient of nitrile butadiene rubber is 1.5, the friction coefficient of traditional polyester polyurethane is 0.9, and the friction coefficient of tempered polyether polyurethane is only 0.18, respectively is one eighth and one fifth of the nitrile butadiene rubber and traditional polyester polyurethane, so its wear is much smaller than that of traditional sealing materials. This provides the necessary guarantee for the long service life of tempered polyether polyurethane.