Sedelon Seal Face Material Selection Factors

The seal face is of great significance of valves, and the quality of it directly affects the service life of valves. In addition, the material of seal face is an important element to ensure its quality. Therefore, there are five factors when choosing valve seal face material.

1.Corrosion resistance

“Corrosion” refers to the process that the seal face is damaged under the action of medium. If the surface is damaged, the sealing performance cannot be guaranteed. Therefore, the material must be corrosion-resistant. The corrosion resistance mainly depends on the chemical stability of materials.

2.Scratch resistance

“Scratch”refers to the material damage caused by friction during the relative movement of the seal face, which will inevitably result in the damage of seal face. Thus, the seal face material must have good scratch resistance, especially the gate valve. The scratch resistance is usually decided by the internal properties of materials.

3.Erosion resistance

“Erosion”means the process that the seal face is damaged when the medium flows through at high speed. This kind of damage is more obvious in throttle valves and safety valves used in high-temperature and high-pressure steam media, greatly influencing sealing performance. Hence, erosion resistance is one of the vital requirements of seal face materials.

4.When used at high temperature, the seal face should have sufficient oxidation resistance as well as thermal fatigue resistance.

5.The coefficient of linear expansion of the seal face and the body material should be similar, which is more important for the structure of the seal ring, so as to avoid additional stress and looseness at high temperature.