Butterfly valve soft seal:
The two sides of the sealing pair are made of metal materials, and the other side is made of elastic non-metallic materials, which is called "soft sealing". The sealing performance is good, but it is not resistant to high temperature, easy to wear, and poor in mechanical properties. Such as: steel rubber, steel tetrafluoroethylene, etc. The soft seal seat is made of non-metallic materials with a certain strength, hardness, and temperature resistance, which has good sealing performance and can achieve zero leakage, but has poor life and temperature adaptability.
Hard seal:
The two sides of the sealing pair are made of metal materials or other hard materials, known as "hard seals". The sealing performance is poor, but it has high temperature resistance, wear resistance, and good mechanical properties. Such as: steel, copper, steel graphite, steel alloy steel; (The steel here can also be cast iron, cast steel, alloy steel, or surfacing, spraying alloy.).

The hard seal of butterfly valves (butterfly valve manufacturers) is made of metal and has relatively poor sealing performance, although some manufacturers claim to achieve zero leakage. Soft sealing cannot meet the process requirements of some corrosive materials, and hard sealing can solve the problem! These two types of seals can complement each other. In terms of sealing, soft sealing is relatively good, but now hard sealing can also meet the corresponding requirements! The advantages of soft sealing are good sealing performance, while the disadvantages are easy aging, wear, and short service life. Hard seals have a long service life, but their sealing performance is worse than soft seals.