单向阀又称止回阀或逆止阀。用于液压系统中防止油流反向流动,或者用于气动系统中防止压缩空气逆向流动。

单向阀是流体只能沿进水口流动，出水口介质却无法回流，俗称单向阀。

单向阀有直通式和直角式两种。直通式单向阀用螺纹连接安装在管路上。直角式单向阀有螺纹连接、板式连接和法兰连接三种形式。液控单向阀也称闭锁阀或保压阀，它与单向阀相同，用以防止油液反向流动。但在液压回路中需要油流反向流动时又可利用控制油压，打开单向阀，使油流在两个方向都可流动。液控单向阀采用锥形阀芯，因此密封性能好。在要求封闭油路时，可用此阀作为油路的单向锁紧而起保压作用。液控单向阀控制油的泄漏方式有内泄式和外泄式二种。在油流反向出口无背压的油路中可用内泄式；否则需用外泄式，以降低控制油压力。

单向阀是气流只能一个方向流动而不能反向流动的方向控制阀。其工作原理与液压单向阀一样。压缩空气从P口进入，克服弹簧力和摩擦力使单向阀阀口开启，压缩空气从P流至A；当P口无压缩空气时，在弹簧力和A口(腔)余气力作用下；阀口处于关闭状 态，使从A至P气流不通。单向阀应用于不允许气流反向流动的场合，如空压机向气罐充气 时，在空压机与气罐之间设置一单向阀，当空压机停止工作时，可防止气罐中的压缩空气回流 到空压机。单向阀还常与节流阀、顺序阀等组合成单向节流阀、单向顺序阀使用。

安装位置

单向阀就是止回阀 旋启式止回阀安装位置不受限制，通常安装于水平管路，但也可以安装于垂直管路或倾斜管路上。

注意事项

安装止回阀时，应特别注意介质流动方向，应使介质正常流动方向与阀体上指示的箭头方向相一致，否则就会截断介质的正常流动。底阀应安装在水泵吸水管路的底端。

止回阀关闭时，会在管路中产生水锤压力，严重时会导致阀门、管路或设备的损坏，尤其对于大口管路或高压管路，故应引起止回阀选用者的高度注意。

止回阀只供防止各类管路或设备上流体介质逆流的单向启闭阀。

Z1S6C1-3X/V

Z1S6D1-3X/V

Z1S6E1-3X/V

Z1S6F1-3X/V

Z1S6P1-3X/V

Z1S6P1-3X/V W

Z1S6P2-3X/V

Z1S6T1-3X/V

Z1S6T2-3X/V

Z1S6T3-3X/V

Z1S10D1-3X/V

Z1S10E1-3X/V

Z1S10F1-3X/V

Z1S10P1-3X/V

Z1S10T1-3X/V

Z1S10T2-3X/V

Z1S6A05-4X/V

Z1S6A30-4X/V

Z1S6A50-4X/V

Z1S6B05-4X/V

Z1S6B30-4X/V

Z1S6B50-4X/V

Z1S6C05-4X/V

Z1S6C05-4X/V

Z1S6C05-4X/V/62

Z1S6C30-4X/V

Z1S6C30-4X/V

Z1S6C50-4X/V

Z1S6D05-4X/V

Z1S6D30-4X/V

Z1S6D50-4X/V

Z1S6E05-4X/V

Z1S6E15-4X/V

Z1S6E30-4X/V

Z1S6E50-4X/V

Z1S6F05-4X/V

Z1S6F30-4X/V

Z1S6F50-4X/V

Z1S6P05-4X/V

Z1S6P05-4X/V SO68

Z1S6P05-4X/V SO90

Z1S6P05-4X/V SO2

Z1S6P05-4X/V/62

Z1S6P05-4X/V/62 SO68

Z1S6P15-4X/V

Z1S6P30-4X/V

Z1S6P30-4X/V SO68

Z1S6P30-4X/V SO90

Z1S6P50-4X/V

Z1S6T05-4X/V

Z1S6T05-4X/V/62

Z1S6T15-4X/V

Z1S6T30-4X/V

Z1S6T50-4X/V

Z2S

Z2S6-1-6X/R

Z2S6-1-6X/VR

Z2S6-2-6X/R

Z2S6-2-6X/VR

Z2S6-3-6X/R

Z2S6A1-6X/R

Z2S6A2-6X/R

Z2S6B1-6X/R

Z2S6B2-6X/R

Z2S10-1-3X/R

Z2S10-2-3X/R

Z2S10A1-3X/R

Z2S10B1-3X/R

Z2S16-1-5X/R

Z4S

Z4WE6D24-3X/EG24N9K4

Z4WE6D24-3X/EG24N9K4/V

Z4WE6D24-3X/EG24NK4

Z4WE6D24-3X/EW230N9K4

Z4WE6D24-3X/EG205N9K4

Z4WE6E51-3X/EG24N9K4

Z4WE6E51-3X/EG24N9K4/V

Z4WE6E51-3X/EG24N9K4QMAG24

Z4WE6E51-3X/EW230N9K4

Z4WE6E53-3X/EG24N9K4

Z4WE6E63-3X/EG24N9K4

Z4WE6E63-3X/EG24N9K4/V

Z4WE6E63-3X/EG24N9K4QMAG24

Z4WE6E63-3X/EG24N9K4QMAG24/V

Z4WE6E63-3X/EG24N9K4QMBG24

Z4WE6E63-3X/EG24N9K4QMBG24/V

Z4WE6E63-3X/EG24NK4

Z4WE6E63-3X/EG24NK4QMAG24

Z4WE6E63-3X/EG24NK4QMAG24/V

Z4WE6E63-3X/EG24K4

Z4WE6E63-3X/EG24K4QMAG24

Z4WE6E63-3X/EG24K4QMAG24/62

Z4WE6E63-3X/EG24K4QMBG24

Z4WE6E63-3X/EW230N9K4

Z4WE6E63-3X/EW230N9K4QMAG24

Z4WE6E63-3X/EW230K4

Z4WE6E63-3X/EW230K4QMAG24

Z4WE6E63-3X/EG205N9K4

Z4WE6E68-3X/EG24N9K4

Z4WE6E68-3X/EG24N9K4/V

Z4WE6E68-3X/EG24N9K4/V/60

Z4WE6E68-3X/EG24N9K4QMAG24

Z4WE6E68-3X/EG24N9K4QMAG24/V

Z4WE6E68-3X/EG24N9K4QMBG24

Z4WE6E68-3X/EG24NK4

Z4WE6E68-3X/EG24K4

Z4WE6E68-3X/EG24K4/V

Z4WE6E68-3X/EG24K4QMAG24

Z4WE6E68-3X/EG24K4QMBG24

Z4WE6E68-3X/EW230N9K4

Z4WE6E68-3X/EW230N9K4/V

Z4WE6E68-3X/EG205K4QMAG24

Z4WE6E137-3X/EG24N9K4

Z4WE6E137-3X/EG24N9K4/V

Z4WE6E137-3X/EG24NK4

Z4WE6E137-3X/EG24K4

Z4WE6E137-3X/EG24K4/V

Z4WE6E137-3X/EG24K4QMAG24

Z4WE6E137-3X/EW230N9K4/V

Z4WE6X250-3X/EG24N9K4/V/60

Z4WE6X250-3X/EG24N9K4QMAG24

Z4WE6X250-3X/EG24N9K4QMBG24

Z4WE6X250-3X/EG24K4QMAG24

Z4WE6X250-3X/EG24K4QMBG24

Z4WE6X250-3X/EG205N9K4/V/60

Z4WE6X252-3X/EG24N9K4/60

Z4WE6X252-3X/EG24N9K4/V/60

Z4WE6X253-3X/EG24N9K4/V/60