The advantages of diaphragm valves are similar to those of pinch valves. The closing element is not wetted by the process medium, so it can be made of cheaper materials in the corrosive process medium. The flow of the medium is straight or nearly straight, and produces a small pressure drop, making it an ideal switching operation and avoiding turbulence.
The diaphragm valve can also be used for throttling operation. However, when a throttling position is maintained near the bottom of the valve body, sometimes small particles will cut into small openings in the diaphragm or the bottom of the valve body and cause corrosion. Because the diaphragm is located in the pressure-bearing valve body, the diaphragm valve can handle a slightly higher pressure than the pinch valve, but the total pressure and temperature rating range depends on the toughness of the material or the enhancement of the diaphragm. The flow path of the valve body is related to the toughness of the diaphragm.
Another advantage of the diaphragm valve is that if the diaphragm fails, the valve body can contain the shallow flow, which is better than the pinch valve housing.
The application condition of the diaphragm valve is similar to that of a pinch valve. The rebound of the diaphragm makes it seal along the particles in the fluid, and makes it ideal for operation in slurries, process materials or fluids containing solids.
Post time: Sep-30-2021