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鍛鋼(gang)截止閥(fa)有三(san)種蓋設(she)計形式(shi)。*種是螺栓式(shi)閥(fa)蓋，按這種設(she)計形式(shi)設(she)計的閥(fa)門，其閥(fa)體與閥(fa)蓋用螺栓螺母連接，纏繞式(shi)墊片(pian)（316夾柔性(xing)石墨制造）密封

鍛(duan)鋼閘閥有三(san)(san)種(zhong)(zhong)(zhong)(zhong)閥蓋設計，*種(zhong)(zhong)(zhong)(zhong)是(shi)螺栓型(xing)閥蓋，通(tong)過凹凸面(mian)連(lian)接(jie)，采(cai)用(yong)不銹(xiu)鋼帶與(yu)柔(rou)性(xing)(xing)石墨纏(chan)繞(rao)墊片，按需求也可(ke)采(cai)用(yong)環連(lian)接(jie)，第(di)(di)二種(zhong)(zhong)(zhong)(zhong)是(shi)焊(han)接(jie)型(xing)閥蓋，通(tong)過螺紋密(mi)封(feng)后焊(han)接(jie)，按需求也可(ke)直(zhi)接(jie)采(cai)用(yong)剛性(xing)(xing)焊(han)接(jie)，第(di)(di)三(san)(san)種(zhong)(zhong)(zhong)(zhong)是(shi)自密(mi)封(feng)閥蓋，通(tong)過螺紋與(yu)自密(mi)封(feng)閥蓋連(lian)接(jie)

止回(hui)閥(fa)存在三(san)種不同的設(she)計結構,它們是升降式止回(hui)閥(fa),球式止回(hui)閥(fa)和旋(xuan)啟式止回(hui)閥(fa)