1. Pinch & Diaphragm Valves

2. Pinch Valve

3. Diaphragm Valve There are two main categories of diaphragm valve. The other has a flat, basic flow One has a saddle, used to restrict the flow

4. Applications Both types of valves are best suited to liquids with large particles such as slurry. Other types of valves would struggle to do this. For corrosive and abrasive applications, different materials can be used for the membranes. Materials like rubbers, silicone and nitrile. The bodies of the valve can be made from a massive variety of materials, varying from brass and steels to plastics. For both types of valve, the components never come into contact with the liquids, unless the membrane splits. This, in turn, improves the durability of the valves.

5. Operating Method Both Diaphragm and Pinch vales can be operated by using a knob or an actuator (which is air driven). The knob/actuator push down on the stem, closing the gap between the valve. This results in the loss of flow. When the opposite is done, obviously, the effect is reversed and re-allows the flow. The air pressure used to close the valve must be 20-40 PSI greater than the process pressure.

6. Advantages & Disadvantages Advantages: 1.Best used for thick/lumpy liquids 2.Very Clean 3.Excellent Drainage 4.Minimal Turbulence 5.Low Maintenance 6.Can be used in explosion proof lines 7.Easy Operation Disadvantages: 1.Cannot be used in high temperature applications 2.Cannot be used in high pressure applications 3.No good for gas usage 4.Different materials required for different applications