The difference between the Soft Seal Butterfly Valve and Hard Seal Butterfly Valve

Author:     Published time:2016-10-13 10:31     Reading times:1072    

 Butterfly valve hard seal: refers to the seal on both sides of the metal material or hard other materials are called "hard seal." This seal is poor sealing performance, but high temperature, wear resistance, mechanical properties. Such as: steel + steel; steel + copper; steel + graphite; steel + alloy steel; (here the steel may be cast iron, cast steel, alloy steel may also be surfacing, spraying alloy)

Soft Seal: Sealing on both sides of the side of the metal material, the other side is a flexible non-metallic materials, known as "soft seal." This seal is better, but not high temperature, easy to wear, Such as: steel + rubber; steel + PTFE, etc. Soft Seal with a certain strength, hardness and temperature performance of non-metallic materials, sealing performance, can be zero leakage, but the life and the The adaptability of the temperature is relatively poor. Hard seals made of metal, sealing performance is relatively poor, although there are manufacturers that can be done to zero leakage. Soft seal on the part of a corrosive materials can not meet the technological requirements, hard seal can be solved! These two seals can complement each other, in terms of sealing the soft seal is relatively good, but now the sealing of the hard seal can meet the corresponding requirements! The advantages of a soft seal sealing performance is good, the disadvantage is easy to aging, wear, short service life. The hard seal has a long service life, but the sealing property is inferior to that of the soft seal.

The structure of the main differences are the following:

1. The structure of the difference: soft-sealed butterfly valves are mostly in-line, hard seal as a single eccentric, double eccentric, three eccentric butterfly valve

2. Temperature: soft seal for normal temperature environment. Hard seal can be used for low temperature, room temperature, high temperature and other environments

3. The pressure: soft seal low - pressure, hard seal can also be used in high pressure and other conditions

4. Sealing performance: soft seal and three eccentric butterfly valve sealing performance is better, three eccentric butterfly valve in high pressure and high temperature environment can maintain a good seal.

In view of the above characteristics, soft sealing butterfly valve for ventilation and dust removal pipeline two-way opening and closing and regulation, water treatment, light industry, petroleum, chemical and other industries. Hard seal butterfly valve for heating, gas, and gas, oil, acid and alkali environment.

With the widespread use of butterfly valve, its easy installation, easy maintenance, the structure is simple and increasingly obvious features. Electric soft sealing butterfly valve, pneumatic soft butterfly valve, hard seal butterfly valve in more and more occasions began to replace the electric gate valve, globe valve and so on.