How to choose valve sealing materials?

Valves are essential components in fluid transport systems, and the sealing performance of valves is directly related to the safety and efficiency of the entire system.

Valve sealing materials can be divided into two main types, metallic and non-metallic, according to their chemical and physical properties. Each material has its specific application conditions, including temperature, pressure, media type, etc. Proper selection of valve sealing materials is essential to ensure long-term stable operation of the valve.

1. Cast iron

Suitable for temperature t ≤ 100 ℃, working pressure PN ≤ 1.6MPa, used for gas and oil gate valves, globe valves, plug valves, and so on.

2. Synthetic rubber

It has good resistance to oil, temperature, and corrosion, and is suitable for globe valves, gate valves, diaphragm valves, butterfly valves, check valves, clamp valves, and so on, with a rated pressure of PN≤1MPa.

3. PTEF

Excellent high temperature and corrosion resistance, applicable to t ≤ 232 ℃, nominal pressure PN ≤ 6.4MPa globe valves, gate valves, ball valves, and so on.

4. Nylon

With a low friction coefficient and good corrosion resistance, suitable for t ≤ 90 ℃, working pressure PN ≤ 32MPa ball valves, globe valves, etc.

5. Copper alloy

With excellent wear resistance, suitable for t ≤ 200 ℃, working pressure PN ≤ 1.6MPa water and steam, widely used in gate valves, globe valves, check valves, plug valves, etc.

6. Chromium stainless steel

After tempering treatment, it has excellent corrosion resistance, suitable for t ≤ 450 ℃, nominal pressure PN ≤ 32MPa water, steam and oil, and other media.

7. Chromium-nickel-titanium stainless steel 

With good corrosion and erosion resistance, and heat resistance, It is suitable for t ≤ 600 ℃, nominal pressure PN ≤ 6.4MPa steam, nitric acid, and other media.

In selecting a valve sealing material, it is essential to consider the type of medium, temperature, pressure, and other factors relevant to the working environment of the valve. Different materials exhibit varying performance characteristics in different working conditions, underscoring the importance of selecting the optimal valve sealing material to ensure the long-term stability and reliability of the valve.