Defects that affect the normal performance of sanitary flanged butterfly valves?

Defects that affect the normal performance of sanitary flanged butterfly valves? 1. Defects in sealing material 1. The disadvantage of sanitary butterfly valve with rubber seal is that when used as a throttle valve, it is easy to be cavitation if used improperly, causing the rubber seat to peel off and the valve seat or rubber seat to be damaged. The alternative to sanitary butterfly valve is to use metal-sealed butterfly valve products, flange check valves or other alternative materials such as PTFE. 2. When the sanitary butterfly valve is in the middle opening, the opening shape formed by the valve body and the front end of the butterfly plate is centered on the valve shaft, and the two sides form different states. The front end of the butterfly plate on one side moves in the direction of the flow water, and the other side It moves against the flow of water. Therefore, one side of the valve body and the valve plate form a nozzle-like opening, and the other side is similar to a throttle opening. The nozzle side has a much faster flow rate than the throttle side, and the throttle side valve will produce Under negative pressure, rubber seals often fall off. 2. Under normal use, the life of the sealing seat of the sanitary butterfly valve is 10-15 years for rubber and 70-85 years for metal under normal conditions. Flow accuracy The relationship between the opening degree of the sanitary butterfly valve and the flow rate basically shows a linear proportional change. If the sanitary butterfly valve is used to control the flow, its flow characteristics are also closely related to the flow resistance of the piping. For example, the sanitary butterfly valve is installed in two pipelines with the same valve diameter and form. However, the pipeline loss coefficient is different, and the flow rate of the valve will also be very different. Big. If the valve is in a state with a large throttle range, the back of the valve plate is prone to cavitation, which may damage the valve. Generally, it is used outside 15°. 3. The self-locking ability of the sanitary butterfly valve can only be realized by installing a worm gear reducer on the valve stem.