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鑄(zhu)鐵止(zhi)(zhi)回(hui)閥(fa)H44T-10又(you)(you)稱單向(xiang)閥(fa)或逆止(zhi)(zhi)閥(fa)，它的啟(qi)閉件是靠介(jie)質(zhi)流(liu)動和(he)力(li)量自行開啟(qi)或關閉，其作用是防止(zhi)(zhi)管路中的介(jie)質(zhi)倒流(liu)。止(zhi)(zhi)回(hui)閥(fa)按結構可分為升降(jiang)(jiang)式(shi)(shi)(shi)(shi)(shi)止(zhi)(zhi)回(hui)閥(fa)、旋啟(qi)式(shi)(shi)(shi)(shi)(shi)止(zhi)(zhi)回(hui)閥(fa)和(he)蝶式(shi)(shi)(shi)(shi)(shi)止(zhi)(zhi)回(hui)閥(fa)三(san)種。升降(jiang)(jiang)式(shi)(shi)(shi)(shi)(shi)止(zhi)(zhi)回(hui)閥(fa)又(you)(you)可分為立式(shi)(shi)(shi)(shi)(shi)和(he)臥式(shi)(shi)(shi)(shi)(shi)兩種；旋啟(qi)式(shi)(shi)(shi)(shi)(shi)止(zhi)(zhi)回(hui)閥(fa)分為單瓣(ban)(ban)式(shi)(shi)(shi)(shi)(shi)、雙瓣(ban)(ban)式(shi)(shi)(shi)(shi)(shi)和(he)多瓣(ban)(ban)式(shi)(shi)(shi)(shi)(shi)三(san)種；蝶式(shi)(shi)(shi)(shi)(shi)止(zhi)(zhi)回(hui)閥(fa)為直(zhi)通式(shi)(shi)(shi)(shi)(shi)。