Sanitary Diaphragm Valve The valve body and corrosion-resistant diaphragm with corrosion-resistant lining are used to replace the valve core assembly, and the movement of the diaphragm is used for regulation. The valve body material of the diaphragm valve is cast iron, cast steel, or cast stainless steel, and is lined with various corrosion-resistant or wear-resistant materials, diaphragm materials rubber and polytetrafluoroethylene. The lined diaphragm has strong corrosion resistance and is suitable for regulating strong corrosive media such as strong acids and strong alkalis.
The diaphragm valve has a simple structure, small fluid resistance, and a larger flow capacity than other types of valves of the same specification; it has no leakage and can be used for regulating high viscosity and suspended particle media. The diaphragm isolates the medium from the upper cavity of the valve stem, so there is no packing and the medium will not leak out. However, due to the limitations of the diaphragm and lining materials, the pressure resistance and temperature resistance are poor, and it is generally only suitable for a nominal pressure of 1.6MPa and below 150℃.
The flow characteristics of the diaphragm valve are close to the fast opening characteristics, which are approximately linear before 60% of the stroke, and the flow changes little after 60%. Pneumatic diaphragm valves can also be equipped with feedback signals, limiters and positioners to meet the needs of automatic control, program control or flow regulation. The feedback signal of the pneumatic diaphragm valve adopts contactless sensing technology. This product uses a thin film propulsion cylinder to replace the piston cylinder, eliminating the disadvantages of the piston ring being easily damaged, causing leakage and failing to push the valve to open and close. When the air source fails, the hand wheel can still be operated to open and close the valve.
The issue that users are concerned about is how to buy genuine pneumatic diaphragm valves. Today we will teach you three methods. Through the observation of these three details, everyone will know how to distinguish the quality of pneumatic diaphragm valves.
1. We can use a strength test to test the quality of buried fully welded ball valves. First, we can weld high-pressure caps on the sleeves on both sides of the buried fully welded ball valve, open the valve to 45 degrees Celsius, and then inject water into the ball valve through the pressure test valve on the sleeve, increase the pressure to 1.5 times the nominal pressure of the ball valve, and maintain the pressure for 15 minutes. If there is no leakage, the ball valve is qualified.

2. We can also test the quality of the buried fully welded ball valve by testing its tightness. The specific operation is as follows: First, close the ball, and then inject nitrogen into the ball valve from the pressure test valve on the sleeve until the pressure rises to 1.1 times the nominal pressure of the ball valve. Then, the middle cavity pressure relief valve is connected to the hose through the water container for testing. The insertion depth is 1cm. If no bubbles are generated within five minutes, the product is qualified.

3. The packaging box should generally contain the product's certificate of conformity, instruction manual and other relevant information. When we buy the Emiton hand chain hoist, we must carefully check these to see if it is a qualified product.
When purchasing a pneumatic diaphragm valve, you can determine whether the product you purchased is genuine by checking the above three details. If you have any other questions, you can ask our staff at any time.