Ball is a sphere with a circular channel for gate parts, ball rotation with the stem of the valve action to achieve headstock.

 
  • 球閥是用帶有圓形通道的球體作啟閉件,球體隨閥桿轉動(dòng)實(shí)現啟閉動(dòng)作的閥門(mén)。
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