止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)啟閉件(jian)靠介(jie)質(zhi)(zhi)流(liu)動(dong)(dong)(dong)(dong)和(he)力(li)(li)(li)量(liang)自行開啟或關閉,以(yi)防(fang)(fang)止(zhi)(zhi)(zhi)(zhi)(zhi)介(jie)質(zhi)(zhi)倒(dao)(dao)流(liu)的(de)(de)(de)閥(fa)(fa)(fa)(fa)(fa)門(men)叫止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)。止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)屬于自動(dong)(dong)(dong)(dong)閥(fa)(fa)(fa)(fa)(fa)類(lei),主(zhu)要(yao)用(yong)(yong)于介(jie)質(zhi)(zhi)單向(xiang)(xiang)流(liu)動(dong)(dong)(dong)(dong)的(de)(de)(de)管(guan)(guan)道上,只允許介(jie)質(zhi)(zhi)向(xiang)(xiang)一(yi)個方向(xiang)(xiang)流(liu)動(dong)(dong)(dong)(dong),以(yi)防(fang)(fang)止(zhi)(zhi)(zhi)(zhi)(zhi)發生(sheng)事故(gu)。止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)又(you)稱單向(xiang)(xiang)閥(fa)(fa)(fa)(fa)(fa)或逆止(zhi)(zhi)(zhi)(zhi)(zhi)閥(fa)(fa)(fa)(fa)(fa),水(shui)泵吸水(shui)關的(de)(de)(de)底閥(fa)(fa)(fa)(fa)(fa)也(ye)屬于止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)類(lei)。止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)是能(neng)自動(dong)(dong)(dong)(dong)阻(zu)止(zhi)(zhi)(zhi)(zhi)(zhi)流(liu)體(ti)(ti)倒(dao)(dao)流(liu)的(de)(de)(de)閥(fa)(fa)(fa)(fa)(fa)門(men)。止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)的(de)(de)(de)閥(fa)(fa)(fa)(fa)(fa)瓣在(zai)流(liu)體(ti)(ti)壓力(li)(li)(li)作用(yong)(yong)下(xia)開啟,流(liu)體(ti)(ti)從進口(kou)(kou)側流(liu)向(xiang)(xiang)出(chu)口(kou)(kou)側。當(dang)進口(kou)(kou)側壓力(li)(li)(li)低(di)于出(chu)口(kou)(kou)側時,閥(fa)(fa)(fa)(fa)(fa)瓣在(zai)流(liu)體(ti)(ti)壓差、本身(shen)重力(li)(li)(li)等因素作用(yong)(yong)下(xia)自動(dong)(dong)(dong)(dong)關閉以(yi)防(fang)(fang)止(zhi)(zhi)(zhi)(zhi)(zhi)流(liu)體(ti)(ti)倒(dao)(dao)流(liu)。止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)關閉時,會(hui)在(zai)管(guan)(guan)路(lu)(lu)(lu)(lu)中(zhong)(zhong)產(chan)(chan)生(sheng)水(shui)錘壓力(li)(li)(li),嚴重時會(hui)導致(zhi)閥(fa)(fa)(fa)(fa)(fa)門(men)、管(guan)(guan)路(lu)(lu)(lu)(lu)或設備(bei)的(de)(de)(de)損壞,尤其對于大口(kou)(kou)管(guan)(guan)路(lu)(lu)(lu)(lu)或高(gao)壓管(guan)(guan)路(lu)(lu)(lu)(lu),故(gu)應引起止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)選(xuan)用(yong)(yong)者的(de)(de)(de)高(gao)度注(zhu)意(yi)。在(zai)管(guan)(guan)線中(zhong)(zhong)不要(yao)使止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)承受重量(liang),大型的(de)(de)(de)止(zhi)(zhi)(zhi)(zhi)(zhi)回(hui)(hui)(hui)(hui)閥(fa)(fa)(fa)(fa)(fa)應獨立支撐,使之不受管(guan)(guan)系產(chan)(chan)生(sheng)的(de)(de)(de)壓力(li)(li)(li)的(de)(de)(de)影響。安裝時注(zhu)意(yi)介(jie)質(zhi)(zhi)流(liu)動(dong)(dong)(dong)(dong)的(de)(de)(de)方向(xiang)(xiang)應與閥(fa)(fa)(fa)(fa)(fa)體(ti)(ti)所(suo)票箭頭方向(xiang)(xiang)一(yi)致(zhi)。
形式種類
止回閥按結構劃分,可分為升降式止回閥、旋啟式止回閥和(he)蝶式(shi)(shi)(shi)(shi)(shi)止回(hui)閥(fa)三(san)種(zhong)。升(sheng)降(jiang)式(shi)(shi)(shi)(shi)(shi)止回(hui)閥(fa)可分(fen)為立式(shi)(shi)(shi)(shi)(shi)和(he)臥(wo)式(shi)(shi)(shi)(shi)(shi)兩(liang)種(zhong)。旋(xuan)啟式(shi)(shi)(shi)(shi)(shi)止回(hui)閥(fa)分(fen)為單瓣(ban)式(shi)(shi)(shi)(shi)(shi)、雙瓣(ban)式(shi)(shi)(shi)(shi)(shi)和(he)多瓣(ban)式(shi)(shi)(shi)(shi)(shi)三(san)種(zhong)。蝶式(shi)(shi)(shi)(shi)(shi)止回(hui)閥(fa)為直(zhi)通式(shi)(shi)(shi)(shi)(shi)、以上幾種(zhong)止回(hui)閥(fa)在連(lian)接(jie)形式(shi)(shi)(shi)(shi)(shi)上可分(fen)為螺(luo)紋連(lian)接(jie)、法(fa)蘭連(lian)接(jie)和(he)焊(han)接(jie)三(san)種(zhong)。
1、升降式(shi)止(zhi)(zhi)回(hui)(hui)閥(fa)(fa)的(de)結構一(yi)般(ban)與(yu)截止(zhi)(zhi)閥(fa)(fa)相似,其閥(fa)(fa)瓣沿著通(tong)道中以線作升降運動(dong),動(dong)作可(ke)(ke)靠(kao),但流體(ti)阻力較大,適(shi)用于輕小口徑的(de)場合(he)。升降式(shi)止(zhi)(zhi)回(hui)(hui)閥(fa)(fa)可(ke)(ke)直(zhi)通(tong)式(shi)和立(li)式(shi)兩種。直(zhi)通(tong)式(shi)升降止(zhi)(zhi)回(hui)(hui)閥(fa)(fa)一(yi)般(ban)只能安裝在(zai)水平管路(lu),而立(li)式(shi)升降止(zhi)(zhi)回(hui)(hui)閥(fa)(fa)一(yi)般(ban)就安裝在(zai)垂直(zhi)管路(lu)。
2、旋(xuan)啟(qi)(qi)(qi)式(shi)止(zhi)(zhi)回(hui)閥(fa)的閥(fa)瓣(ban)(ban)(ban)繞轉(zhuan)軸作旋(xuan)轉(zhuan)運動。其(qi)流(liu)體阻力(li)一(yi)般小于升降式(shi)止(zhi)(zhi)回(hui)閥(fa),它適(shi)用(yong)于較(jiao)大口徑(jing)(jing)的場合。旋(xuan)啟(qi)(qi)(qi)式(shi)止(zhi)(zhi)回(hui)閥(fa)根據閥(fa)瓣(ban)(ban)(ban)的數目(mu)可分為單(dan)瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)、雙瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)及多瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)三種。單(dan)瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)止(zhi)(zhi)回(hui)閥(fa)一(yi)般適(shi)用(yong)于中(zhong)等(deng)口徑(jing)(jing)的場合。大口徑(jing)(jing)管(guan)路(lu)選(xuan)用(yong)單(dan)瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)止(zhi)(zhi)回(hui)閥(fa)時,為減(jian)(jian)少(shao)水錘壓(ya)力(li),最好(hao)采用(yong)能(neng)減(jian)(jian)小水錘壓(ya)力(li)的緩閉止(zhi)(zhi)回(hui)閥(fa)。雙瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)止(zhi)(zhi)回(hui)閥(fa)適(shi)用(yong)于大中(zhong)口徑(jing)(jing)管(guan)路(lu)。對夾雙瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)止(zhi)(zhi)回(hui)閥(fa)結構小、重量輕(qing),是一(yi)種發展較(jiao)快的止(zhi)(zhi)回(hui)閥(fa);多瓣(ban)(ban)(ban)旋(xuan)啟(qi)(qi)(qi)式(shi)止(zhi)(zhi)回(hui)閥(fa)適(shi)用(yong)于大口徑(jing)(jing)管(guan)路(lu)。
3、隔膜式止回(hui)閥有多種結構形式,均采用(yong)隔膜作為啟閉件,由(you)于其防(fang)水錘性能好,結構簡單(dan),成本低,近年(nian)來(lai)發展較快。但隔膜式止回(hui)閥的使用(yong)溫度和壓力受到隔膜材料的限(xian)制。
4、球型(xing)污(wu)水止回閥(fa):閥(fa)體采用(yong)全通道結(jie)構(gou),具有流量大、阻力小之(zhi)優點。采用(yong)圓球做(zuo)閥(fa)瓣,適用(yong)于高粘度、有懸(xuan)浮物(wu)的工業(ye)及生活污(wu)水管(guan)網
5、蝶(die)式(shi)止回閥的結構類似于蝶(die)閥。其(qi)結構簡單、流(liu)阻較(jiao)小(xiao),水錘壓力亦較(jiao)小(xiao)。
主要特點
1、結構長度短,其(qi)結構長度只有傳統(tong)法蘭止回閥的1/4~1/8
2、體積(ji)小、重量(liang)輕、其(qi)重量(liang)只有傳統法蘭止回閥的1/4~1/20
3、閥(fa)瓣關閉快速,水錘壓力小
4、水平(ping)或垂直管道均可使用,安裝方便
5、流道通暢、流體阻力小
6、動作靈敏、密封性能好
7、閥瓣(ban)行程短(duan)、關閥沖擊力(li)小
8、整體結構、簡(jian)單緊(jin)湊、造型美觀
9、使用(yong)壽命(ming)長(chang)、可(ke)靠性高(gao)
安裝與維護
1、在管(guan)線中不(bu)要使止回閥承(cheng)受(shou)重(zhong)量,大型的(de)止回閥應獨立支撐,使之不(bu)受(shou)管(guan)系產生的(de)壓力的(de)影(ying)響。
2、升降式垂(chui)直瓣止回閥應(ying)安裝(zhuang)在垂(chui)直管道(dao)上。
3、升降式水平瓣止回閥應安裝在水平管道上。
4、安裝止(zhi)回閥時,應(ying)(ying)特別(bie)注意介(jie)質(zhi)流(liu)動方(fang)(fang)向(xiang),應(ying)(ying)使介(jie)質(zhi)正常流(liu)動方(fang)(fang)向(xiang)與閥體上指示的箭頭方(fang)(fang)向(xiang)相一致(zhi),否則就會截斷介(jie)質(zhi)的正常流(liu)動。底閥應(ying)(ying)安裝在水泵吸水管路的底端(duan)。
5、旋啟(qi)式止回閥安(an)裝位(wei)置不妥限制,通常安(an)裝于(yu)水(shui)平管(guan)路(lu),但也可以安(an)裝于(yu)垂(chui)直管(guan)路(lu)或傾料管(guan)路(lu)上。
6、通式升(sheng)(sheng)降(jiang)式止回(hui)(hui)閥(fa)(fa)應安裝于水(shui)平管(guan)(guan)路上,立式升(sheng)(sheng)降(jiang)式止回(hui)(hui)閥(fa)(fa)和底閥(fa)(fa)一般安裝在垂直管(guan)(guan)路上,并且介質自下而上流(liu)動(dong)。
7、單瓣旋啟(qi)式止(zhi)(zhi)回(hui)閥一般適用(yong)于(yu)中等(deng)口徑(jing)的場合。大口徑(jing)管路選用(yong)單瓣旋啟(qi)式止(zhi)(zhi)回(hui)閥時,為(wei)減少水(shui)錘壓力,最好采用(yong)能減小(xiao)水(shui)錘壓力的緩閉(bi)止(zhi)(zhi)回(hui)閥。
8、雙瓣旋(xuan)啟(qi)式(shi)(shi)止(zhi)回(hui)閥適(shi)用于大中口徑管路。對夾雙瓣旋(xuan)啟(qi)式(shi)(shi)止(zhi)回(hui)閥結構小(xiao)、重(zhong)量輕,是一種發展較快的止(zhi)回(hui)閥;多瓣旋(xuan)啟(qi)式(shi)(shi)止(zhi)回(hui)閥適(shi)用于大口徑管路。