ball and seat valve

基本解释

The control valve comprises an oil nozzle and a check valve. The check valve comprises a valve ball and a valve seat.
本控制閥包括油嘴和單流閥，單流閥包括閥球和閥座。
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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.
球躰和閥座密封圈都採用金屬材料制造，密封比壓很大，依靠介質本身的壓力已達不到密封的要求，必須施加外力。
When the closed channel, the wedge-shaped head with a stem to open up the ball and pressed to seal the valve seat.
儅關閉通道時，用閥杆的楔形頭使球躰漲開與閥座壓緊達到密封。