美國(guó)DFT公司已經(jīng)有超過(guò)65年的歷史，專注于單向閥的設(shè)計(jì)和制造，DFT單向閥以防止和去除
管道系統(tǒng)的水錘現(xiàn)象而聞名。美國(guó)DFT*初設(shè)計(jì)的基本型單向閥是為了滿足一個(gè)客戶的小型金屬密封
單向閥要求，隨著幾十年的發(fā)展，現(xiàn)在已形成一個(gè)全系列產(chǎn)品，共十大系列ALC®，DLC®，
DSV®，Excalibur®，F(xiàn)BC®,GLC®,GPV®,PDC®,SCV®和WLC®,每一個(gè)系列都對(duì)應(yīng)一種特殊的用途。 

美國(guó)DFT傳統(tǒng)單向閥（旋啟式單向閥）一般依靠閥盤自重或介質(zhì)反向作用力關(guān)閉閥門。如事故停泵后介質(zhì)開
始倒流，在倒泄介質(zhì)的作用下，單向閥迅速關(guān)閉，由于閥座摩阻及介質(zhì)慣性的影響，美國(guó)DFT單向閥關(guān)閉通常滯后于開始倒流的時(shí)間，即在倒流量增至一定值，甚至在*大倒流量的瞬間迅速關(guān)閉，則能在單向閥處產(chǎn)生非常大的壓力。壓力峰值高，而且持續(xù)時(shí)間較長(zhǎng)，*易產(chǎn)生水錘 。 

美國(guó)DFT緩沖式單向閥：采用彈簧復(fù)位，緩沖式設(shè)計(jì)，可以去除或*大限度減小水錘效應(yīng)。閥門有優(yōu)化的關(guān)閉特性，如在突然停泵時(shí)可迅速關(guān)閉，阻止介質(zhì)倒流保護(hù)水泵不致發(fā)生反轉(zhuǎn)，達(dá)到保護(hù)水泵的目的；且可在關(guān)閉的*后階段實(shí)現(xiàn)緩閉，減少突然關(guān)閉造成管路中的水錘，達(dá)到保護(hù)管路的目的。壓力峰值小，持續(xù)時(shí)間短，避免了如其它形式單向閥閥盤撞擊閥座產(chǎn)生的水錘現(xiàn)象，降低系統(tǒng)噪音，并防止管路系統(tǒng)損壞。
 
經(jīng)營(yíng)產(chǎn)品：
美國(guó)DFT單向閥、美國(guó)DFT控制閥、美國(guó)DFT調(diào)節(jié)閥等
 
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