球体和阀座密封圈都采用金属材料制造，密封比压很大，依靠介质本身的压力已达不到密封的要求，必须施加外力。

Ball and valve seat rings are metal materials, sealing pressure than the large, rely on the media itself can not seal the pressure has reached the requirements to be imposed by external forces.

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球阀阀座(密封圈)一般采用聚四氟乙烯等弹性材料制造，易于保证密封，而且球阀的密封力随着介质压力的增加而增大。

Valve seat (ring) generally use the Teflon and other flexible materials, easy-to ensure the seal, and valve sealing force with medium pressure increases.

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而且此产品的软密封结构的密封圈是由金属圈压套在阀座上的阶梯凹槽内，具有密封不脱落，而且可以很方便的更换等优点。

And the structure of the soft sealing ring of this product is pressed by a metal ring set in the seat within a groove on the ladder which can't drop and be convenient to change.

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