May I introduce sealing performance and leakage detection?

Plastic butterfly valve is a commonly used fluid control equipment with the advantages of simple structure, light weight and easy installation. It is widely used in industrial production and piping systems, but its sealing performance and leakage problems have been the focus of attention.

the sealing performance and leakage detection of plastic butterfly valves will be introduced in detail:

1, the sealing performance of plastic butterfly valve

The sealing performance of plastic butterfly valve mainly includes two aspects: static sealing and dynamic sealing.

Static Seal ability

Static tightness means that there is no leakage between the valve body and the sealing surface when the plastic butterfly valve is in the closed state. The main sealing parts of plastic butterfly valve include valve seat, valve plate and sealing ring. The sealing surfaces of the valve seat and valve plate are usually made of materials such as rubber or PTFE, which have good sealing performance. The sealing ring plays a sealing role, can be made of rubber ring, PTFE ring and other materials. In the design and manufacturing process, it is necessary to ensure the flatness, roundness and dimensional accuracy of the sealing surface to ensure the static sealing performance.

Dynamic sealing

Dynamic sealing refers to the plastic butterfly valve in the opening and closing process, no leakage between the valve body and the sealing surface. The dynamic sealing performance of plastic butterfly valve mainly depends on the sealing of the valve stem and packing. The friction between the valve stem and packing is the key to prevent leakage. Materials such as polytetrafluoroethylene packing and flexible graphite packing are usually used as the sealing packing, which has good corrosion resistance and high temperature resistance. During operation, the packing needs to be checked regularly for wear and tear, and maintained and replaced to ensure dynamic sealing performance.

2, the plastic butterfly valve leakage detection

Plastic butterfly valve leakage detection is to ensure the normal operation of the valve and prevent leakage accidents is an important link.

Appearance detection

Appearance detection is mainly through visual observation, check whether the valve body, valve stem, packing and other components have obvious wear, cracks or deformation. At the same time, it is also necessary to check whether the sealing surface has impurities, foreign objects and other influences on the existence of sealing.

Airtightness testing

Gas tightness testing can be performed using a gas tightness tester. The instrument usually applies a certain amount of pressure to the valve and then observes whether there is any gas leakage. If there is leakage, the sealing surfaces and packing need to be checked for proper functioning, maintained and repaired.

Liquid Tightness Testing

Liquid-tightness testing can be performed using a liquid-tightness tester. This instrument usually applies a certain pressure to the valve and then observes whether there is any liquid leakage. If there is leakage, the sealing surface and packing need to be checked for proper functioning, and maintenance and repair should be carried out.

Sonic Detection

Acoustic wave detection is a fast and accurate method of leak detection. Through the use of acoustic wave detection instruments, the sound signal generated when the valve leaks can be detected, and the intensity and frequency of the sound can be used to determine the extent and location of the leak.

In summary, the sealing performance and leakage detection of plastic butterfly valve is the key to ensure the normal operation and safe use of the valve. In the process of design, manufacture and use, it is necessary to pay attention to the selection of suitable sealing materials, strict control of process requirements, and regular leakage detection and maintenance work to ensure the safety and reliability of plastic butterfly valves.