There are many reasons for butterfly valve failure, and the following are some of the main factors
First, mechanical wear
Mechanical wear is one of the common causes of butterfly valve failure. This is mainly due to the frequent opening and closing process of the butterfly valve, the friction between the spool, seat and other components will be generated, and the long-term accumulation will lead to gradual wear of the components, thus affecting the sealing performance. When the wear is serious, the valve can not even be closed tightly, and there is leakage.
2. Corrosion
Corrosion is also an important factor leading to butterfly valve failure. Corrosion can be divided into chemical corrosion and electrochemical corrosion. Chemical corrosion is caused by contact with corrosive media, while electrochemical corrosion is caused by differences in the composition of metal materials or the formation of potential differences with the surrounding environment. Corrosion will gradually thin the metal material of the butterfly valve, reduce its strength, and eventually lead to valve failure.
3. Aging of sealing materials
The sealing materials of butterfly valves, such as rubber and polytetrafluoroethylene, will age due to factors such as temperature, pressure and medium during long-term use. For example, rubber seals will become hard and brittle at high temperatures and lose their elasticity, resulting in reduced sealing performance. The aging of the sealing material will directly affect the sealing effect of the butterfly valve, and will lead to leakage in serious cases.
4. Sealing surface damage
The sealing surface of the butterfly valve may be damaged by wear, corrosion or scratches from impurities. For example, during installation, hard particles may scratch the sealing surface between the spool and the seat, causing the valve to close loosely and leak. In addition, the high sealing specific pressure in the high pressure valve may also damage the sealing surface and reduce the sealing performance.
Five, improper operation
Improper operation is also one of the causes of butterfly valve failure. For example, when manually operating a valve, turning the handwheel with excessive force may damage the valve stem or other internal components. For electric or pneumatic valves, if the control signal is wrong or the operating frequency is out of the design range, it will also lead to valve failure.
Six, the installation is not standardized
Non-standard installation may also lead to butterfly valve failure. For example, failure to ensure the coaxiality of the valve during installation will cause the valve stem to bear unequal forces, which will affect the accuracy and service life of the valve. In addition, if the installation is not carried out according to the correct installation method and requirements, it may also lead to the wrong direction of the valve, poor connection and other problems, which will affect the normal operation of the valve.
Design or manufacturing defects
Defects in the design or manufacture of butterfly valves can also cause them to fail. For example, poorly designed valve structure may lead to poor sealing performance; Quality problems existing in the manufacturing process, such as material defects, insufficient processing accuracy, etc., may also affect the performance and service life of the valve.