傳統(tǒng)的球閥，無論是浮動式或固定式，球體與閥座始終接觸，開關(guān)扭矩大，密封面容易損傷。V型半球控制閥啟閉時，球體先偏轉(zhuǎn)-δ角，然后轉(zhuǎn)動，開關(guān)全過程中球體與閥座脫離，故閥座不會被擦傷，并且啟閉扭矩小，用于調(diào)節(jié)及切斷纖維類介質(zhì)。

The ball and the seat ring is always contact with each other on the traditional ball valve. The torque is big from open to close and the seal face is easy to abrade. This kind of ball valve ,the ball first deflexed –δ，then turns. The ball and the seat ring break away from open to close. So the seat ring can not be abraded