Introduction of internal thread check valve, internal structure of check valve

Internal thread check valve refers to a valve that automatically opens and closes the valve disc by relying on the flow of the medium itself to prevent the medium from backflowing, also known as check valve, check valve, reverse flow valve, and back pressure valve. The check valve is an automatic valve, and its main function is to prevent the backflow of the medium, prevent the pump and the drive motor from reversing, and the discharge of the container medium. Check valves can also be used on lines that supply auxiliary systems where pressure may rise above the system pressure.

Check valves can be mainly divided into swing-type check valves (rotating according to the center of gravity) and lifting check valves (moving along the axis). This type of valve should generally be installed horizontally in the pipeline.

Here are some of the well-known brands recognized in the valve industry, which are widely recognized and have a high reputation. While rankings may vary depending on time and market conditions, the following brands are generally considered to be among the top brands in the valve industry:

The following influential first-line brands of water system valves and industrial valves can be used as a reference, but for reference only: Suzhou Neway Valve, Shanghai Guanlong Valve, Shanghai Qizhong Valve, Sanhua, Su Yan, Shentong, Su Valve, Nanfang, Jiang.

First, the word Yao. The above manufacturers are only estimates and references, and the specific situation may vary or fluctuate at any time due to changes in a series of factors such as changes in the market, the size of the competition pattern, and the stability of product quality. As an indispensable key device in industrial production and civil facilities, the quality and reputation of the valve brand directly affect the satisfaction and trust of users.

These brands are known in the valve industry for their innovative technology, high-quality products and reliability. It is important to note that the market and industry are evolving rapidly, and different rankings may vary depending on time and region. For the most up-to-date ranking information, it is recommended to refer to industry reports, professional organizations or market research data for more detailed and accurate information.

Check valves are mainly composed of valve body, valve cover, valve disc, rocker arm, valve seat, etc

Check valves, also known as check valves or check valves, are used to prevent the backflow of media in the pipeline. The foot valve of the suction off of the branch water pump also belongs to the category of check valves. Forged steel check valves have two body cover connection design forms:

The first is the body cover bolted forged steel check valve, the valve designed according to this connection form, the valve body and the valve cover are bolted together, and the winding gasket is sealed, the advantage is that it is easy to maintain; The second kind of body cover is fully welded and sealed, forged steel check valve, according to this connection form of the design of the valve, the valve body and the valve cover are connected with spiromosquitoes, fully welded seal, the advantage is that there is no leakage. Forged steel check valve disc forms are also available in interception type, needle type and ball type, which can be reasonably selected according to the actual situation. The check valve is an automatic valve, and its main function is to prevent the backflow of the medium, prevent the pump and the drive motor from reversing, and the discharge of the container medium.

1. The check valve refers to the valve whose opening and closing parts are circular discs and rely on their own weight and medium pressure to block the backflow of the residual attack medium. It is often used as a foot valve for pumping devices to prevent the backflow of water. The check valve is used in combination with the globe valve to play the role of safety isolation.

2. The movement mode of the valve disc is divided into lifting type and swing type. The lift-type check valve is similar in structure to the shut-off valve, except that it lacks the stem that drives the disc. The medium flows in from the inlet (bottom) and out from the outlet (top).

The valve is opened when the inlet pressure is greater than the sum of the disc weight and its flow resistance.

3. On the contrary, the valve is closed when the medium flows backwards. The vertical swing check valve has a disc that is tilted and rotates around the shaft, and works similarly to a lift check valve. Check valves are often used as foot valves for pumping devices to stop the backflow of water.

The check valve is used in combination with the globe valve to play the role of safety isolation. The disadvantage is that the resistance is high and the sealing is poor when closed.

Classification of check valves.

Common types of check valves are: butterfly check valves, clamp check valves, swing check valves, vertical check valves, and lifting check valves.

Selection of check valves.

For medium and medium pressure check valves below DN50mm, vertical lifting check valves and straight-through lift check valves should be selected;

For low-pressure check valves below DN50mm, butterfly check valves, vertical lifting check valves and diaphragm check valves should be selected;

For high and medium pressure check valves with DN greater than 50mm and less than 600mm, it is advisable to choose rotary check valves;

For medium and low pressure check valves with DN greater than 200mm and less than 1200mm, it is advisable to choose a wear-free spherical check valve;

For low-pressure check valves with DN greater than 50mm and less than 2000mm, Yi selects butterfly check valve and diaphragm check valve;

For pipelines that require less water hammer impact or no water hammer when closing, it is advisable to choose slow-closing swing-start check valve and slow-closing butterfly check valve.