止回阀的结构与特点止回阀（Check Valve），又称单向阀或逆止阀，是一种自动阀门。核心功能：依靠管路中介质自身的流动产生的力而自动开启和关闭，用于防止介质倒流。它是流体管道系统中的“单向通行证”，只允许介质向一个方向流动，阻止反向流动，从而避免泵和驱动马达反转、容器介质泄放，以及防止水锤对系统和设备的破坏。按结构形式分类升降式止回阀其结构与截止阀相似，阀体和阀瓣与截止阀相同。阀瓣上部和阀盖下部加工有导向套筒，阀瓣导向筒可在阀盖导向筒内自由升降。在阀瓣导向筒下部或阀盖导向套筒上部加工有泄压孔，当阀瓣上升时，排出套筒内的介质，降低阀瓣开启时的阻力。按管道的安装位置分为以下两种:

　　Structure and Characteristics of Check Valve Check valve, also known as one-way valve or check valve, is an automatic valve. Core function: It automatically opens and closes by relying on the force generated by the flow of the medium itself in the pipeline, to prevent medium backflow. It is a "one-way pass" in fluid pipeline systems, allowing only one direction of medium flow and preventing reverse flow, thereby avoiding pump and drive motor reversal, container medium release, and preventing water hammer damage to systems and equipment. Classified by structural form, lift check valves have a structure similar to globe valves, with the same valve body and disc as globe valves. The upper part of the valve disc and the lower part of the valve cover are processed with guide sleeves, and the valve disc guide cylinder can be freely raised and lowered inside the valve cover guide cylinder. There are pressure relief holes machined at the lower part of the valve disc guide cylinder or the upper part of the valve cover guide sleeve. When the valve disc rises, the medium inside the sleeve is discharged, reducing the resistance when the valve disc opens. According to the installation position of the pipeline, it can be divided into the following two types:

　　(1)直通式升降止回阀当介质停止流动时，阀靠自重降落在阀座上可阻止介质倒流。

　　(1) When the medium stops flowing, the straight through lift check valve relies on its own weight to land on the valve seat to prevent the medium from flowing back.

　　(2)立式升降止回阀介质进出口通道方向与阀座通道方向相同，其流动阻力小。

　　(2) The direction of the medium inlet and outlet channels of the vertical lift check valve is the same as that of the valve seat channel, and its flow resistance is small.

　　旋启式止回阀旋启式止回阀的阀瓣呈圆盘状，绕阀座通道的转轴作旋转运动。由于阀内通道成流线形，流动阻力比直通式升降止回阀小，适用于大口径的场合。密封性能不如升降式。缺点是关闭时会产生较大水锤压力，密封面有冲击和磨损，产生噪音，适用于低流速和流动不常变动的场合，不宜用于脉动流。根据阀瓣的数目多少，旋启式止回阀又分为以下三种：

　　The disc of a rotary check valve is disc-shaped and rotates around the axis of the valve seat channel. Due to the linear flow inside the valve, the flow resistance is smaller than that of a straight through lift check valve, making it suitable for large-diameter applications. The sealing performance is not as good as that of the lift type. The disadvantage is that it will generate a large water hammer pressure when closed, and the sealing surface will have impact and wear, generating noise. It is suitable for low flow rates and situations where the flow does not change frequently, and is not suitable for pulsating flow. According to the number of valve discs, swing check valves are divided into the following three types:

　　(1)单瓣式，有一个阀座通道和一个阀瓣。适用于中等口径的旋启式止回阀。

　　(1) Single disc design, with one valve seat channel and one valve disc. Suitable for medium caliber swing check valves.

　　(2)双瓣式有两个阀座通道和两个阀。适用于较大口径(DN>600mm)旋启式止回阀。

　　(2) The double valve has two seat channels and two valves. Suitable for larger diameter (DN>600mm) swing check valves.

　　(3)多瓣式：启闭件是由多个小直径的阀瓣组成。介质停止流动时或倒流时，小阀瓣不会同时关闭，可以减弱水力冲击。由于阀瓣重量轻，关闭动作平稳，所以阀瓣对阀座的撞击力较小，不会造成密封面的损坏。适用于DN>600mm的止回阀。

　　(3) Multi disc type: The opening and closing component is composed of multiple small diameter valve discs. When the medium stops flowing or flows back, the small valve disc will not close at the same time, which can reduce hydraulic shock. Due to the light weight and smooth closing action of the valve disc, the impact force of the valve disc on the valve seat is relatively small, and it will not cause damage to the sealing surface. Suitable for check valves with DN>600mm.

　　压紧式止回阀压紧式止回阀做为锅炉给水和蒸汽切断用阀，它具有升降式止回阀和截止阀或角阀的综合机能。阀杆和阀瓣并不直接连结。仅在锅炉试压或停汽时需要关闭阀门，才操作手轮或者当并联的锅炉，其中一台发生故障时，此阀背面压力增大而关闭，然后再旋转手轮，将阀瓣压紧在阀座上。它是开闭和逆止机能同时存在的阀门。

　　Compression type check valve, as a valve for boiler feedwater and steam shut-off, has the comprehensive function of a lift type check valve and a globe valve or angle valve. The valve stem and valve disc are not directly connected. Only when the valve needs to be closed during boiler pressure testing or steam shutdown, should the handwheel be operated or when one of the parallel boilers fails, the pressure on the back of the valve increases and closes, and then the handwheel is rotated to press the valve disc tightly onto the valve seat. It is a valve with both opening and closing functions and check function.

　　其余止回阀还有用于泵吸入管的吸入口处使用的底阀，蝶式止回阀、球式止回阀等。

　　Other check valves include bottom valves used at the suction inlet of pump suction pipes, butterfly check valves, ball check valves, etc.

　　注意事项：(1)直通式升降止回阀应安装在水平管道上;立式升降止回阀、球式止回阀2和底阀必须安装在垂直管道上，并要求介质自下而上流动。

　　Attention: (1) The straight through lift check valve should be installed on a horizontal pipeline; Vertical lift check valve, ball check valve 2, and bottom valve must be installed on vertical pipelines, and the medium is required to flow from bottom to top.

　　(2)旋启式止回阀一般安装在水平管道上，也可安装在垂直管道或倾斜管道上。

　　(2) Swing check valves are generally installed on horizontal pipelines, but can also be installed on vertical or inclined pipelines.

　　(3)小口径管道上选用升降式止回阀，大口径管道上选用旋启式止回阀。

　　(3) Lift check valves are used on small-diameter pipelines, while swing check valves are used on large-diameter pipelines.

　　(4)安装止回阀时要注意介质流动方向与止回阀箭头指示方向一致。

　　(4) When installing a check valve, pay attention to the direction of medium flow being consistent with the direction indicated by the check valve arrow.

　　本文由  良工阀门 友情奉献.更多有关的知识请点击  http://www.jnlgvf.com/   真诚的态度.为您提供为全面的服务.更多有关的知识我们将会陆续向大家奉献.敬请期待.　　止回阀的结构与特点止回阀（Check Valve），又称单向阀或逆止阀，是一种自动阀门。核心功能：依靠管路中介质自身的流动产生的力而自动开启和关闭，用于防止介质倒流。它是流体管道系统中的“单向通行证”，只允许介质向一个方向流动，阻止反向流动，从而避免泵和驱动马达反转、容器介质泄放，以及防止水锤对系统和设备的破坏。按结构形式分类升降式止回阀其结构与截止阀相似，阀体和阀瓣与截止阀相同。阀瓣上部和阀盖下部加工有导向套筒，阀瓣导向筒可在阀盖导向筒内自由升降。在阀瓣导向筒下部或阀盖导向套筒上部加工有泄压孔，当阀瓣上升时，排出套筒内的介质，降低阀瓣开启时的阻力。按管道的安装位置分为以下两种:

　　This article is a friendly contribution from Lianggong Valve For more related knowledge, please click http://www.jnlgvf.com/ Sincere attitude To provide you with comprehensive services We will gradually contribute more relevant knowledge to everyone Coming soon. Structure and Characteristics of Check Valve Check valve, also known as one-way valve or check valve, is an automatic valve. Core function: It automatically opens and closes by relying on the force generated by the flow of the medium itself in the pipeline, to prevent medium backflow. It is a "one-way pass" in fluid pipeline systems, allowing only one direction of medium flow and preventing reverse flow, thereby avoiding pump and drive motor reversal, container medium release, and preventing water hammer damage to systems and equipment. Classified by structural form, lift check valves have a structure similar to globe valves, with the same valve body and disc as globe valves. The upper part of the valve disc and the lower part of the valve cover are processed with guide sleeves, and the valve disc guide cylinder can be freely raised and lowered inside the valve cover guide cylinder. There are pressure relief holes machined at the lower part of the valve disc guide cylinder or the upper part of the valve cover guide sleeve. When the valve disc rises, the medium inside the sleeve is discharged, reducing the resistance when the valve disc opens. According to the installation position of the pipeline, it can be divided into the following two types:

　　(1)直通式升降止回阀当介质停止流动时，阀靠自重降落在阀座上可阻止介质倒流。

　　(1) When the medium stops flowing, the straight through lift check valve relies on its own weight to land on the valve seat to prevent the medium from flowing back.

　　(2)立式升降止回阀介质进出口通道方向与阀座通道方向相同，其流动阻力小。

　　(2) The direction of the medium inlet and outlet channels of the vertical lift check valve is the same as that of the valve seat channel, and its flow resistance is small.

　　旋启式止回阀旋启式止回阀的阀瓣呈圆盘状，绕阀座通道的转轴作旋转运动。由于阀内通道成流线形，流动阻力比直通式升降止回阀小，适用于大口径的场合。密封性能不如升降式。缺点是关闭时会产生较大水锤压力，密封面有冲击和磨损，产生噪音，适用于低流速和流动不常变动的场合，不宜用于脉动流。根据阀瓣的数目多少，旋启式止回阀又分为以下三种：

　　The disc of a rotary check valve is disc-shaped and rotates around the axis of the valve seat channel. Due to the linear flow inside the valve, the flow resistance is smaller than that of a straight through lift check valve, making it suitable for large-diameter applications. The sealing performance is not as good as that of the lift type. The disadvantage is that it will generate a large water hammer pressure when closed, and the sealing surface will have impact and wear, generating noise. It is suitable for low flow rates and situations where the flow does not change frequently, and is not suitable for pulsating flow. According to the number of valve discs, swing check valves are divided into the following three types:

　　(1)单瓣式，有一个阀座通道和一个阀瓣。适用于中等口径的旋启式止回阀。

　　(1) Single disc design, with one valve seat channel and one valve disc. Suitable for medium caliber swing check valves.

　　(2)双瓣式有两个阀座通道和两个阀。适用于较大口径(DN>600mm)旋启式止回阀。

　　(2) The double valve has two seat channels and two valves. Suitable for larger diameter (DN>600mm) swing check valves.

　　(3)多瓣式：启闭件是由多个小直径的阀瓣组成。介质停止流动时或倒流时，小阀瓣不会同时关闭，可以减弱水力冲击。由于阀瓣重量轻，关闭动作平稳，所以阀瓣对阀座的撞击力较小，不会造成密封面的损坏。适用于DN>600mm的止回阀。

　　(3) Multi disc type: The opening and closing component is composed of multiple small diameter valve discs. When the medium stops flowing or flows back, the small valve disc will not close at the same time, which can reduce hydraulic shock. Due to the light weight and smooth closing action of the valve disc, the impact force of the valve disc on the valve seat is relatively small, and it will not cause damage to the sealing surface. Suitable for check valves with DN>600mm.

　　压紧式止回阀压紧式止回阀做为锅炉给水和蒸汽切断用阀，它具有升降式止回阀和截止阀或角阀的综合机能。阀杆和阀瓣并不直接连结。仅在锅炉试压或停汽时需要关闭阀门，才操作手轮或者当并联的锅炉，其中一台发生故障时，此阀背面压力增大而关闭，然后再旋转手轮，将阀瓣压紧在阀座上。它是开闭和逆止机能同时存在的阀门。

　　Compression type check valve, as a valve for boiler feedwater and steam shut-off, has the comprehensive function of a lift type check valve and a globe valve or angle valve. The valve stem and valve disc are not directly connected. Only when the valve needs to be closed during boiler pressure testing or steam shutdown, should the handwheel be operated or when one of the parallel boilers fails, the pressure on the back of the valve increases and closes, and then the handwheel is rotated to press the valve disc tightly onto the valve seat. It is a valve with both opening and closing functions and check function.

　　其余止回阀还有用于泵吸入管的吸入口处使用的底阀，蝶式止回阀、球式止回阀等。

　　Other check valves include bottom valves used at the suction inlet of pump suction pipes, butterfly check valves, ball check valves, etc.

　　注意事项：(1)直通式升降止回阀应安装在水平管道上;立式升降止回阀、球式止回阀2和底阀必须安装在垂直管道上，并要求介质自下而上流动。

　　Attention: (1) The straight through lift check valve should be installed on a horizontal pipeline; Vertical lift check valve, ball check valve 2, and bottom valve must be installed on vertical pipelines, and the medium is required to flow from bottom to top.

　　(2)旋启式止回阀一般安装在水平管道上，也可安装在垂直管道或倾斜管道上。

　　(2) Swing check valves are generally installed on horizontal pipelines, but can also be installed on vertical or inclined pipelines.

　　(3)小口径管道上选用升降式止回阀，大口径管道上选用旋启式止回阀。

　　(3) Lift check valves are used on small-diameter pipelines, while swing check valves are used on large-diameter pipelines.

　　(4)安装止回阀时要注意介质流动方向与止回阀箭头指示方向一致。

　　(4) When installing a check valve, pay attention to the direction of medium flow being consistent with the direction indicated by the check valve arrow.

　　本文由  良工阀门 友情奉献.更多有关的知识请点击  http://www.jnlgvf.com/   真诚的态度.为您提供为全面的服务.更多有关的知识我们将会陆续向大家奉献.敬请期待.

　　This article is a friendly contribution from Lianggong Valve For more related knowledge, please click http://www.jnlgvf.com/ Sincere attitude To provide you with comprehensive services We will gradually contribute more relevant knowledge to everyone Coming soon.