Elastic soft seal gate valve and hard seal gate valve in all aspects of the diff

1. the structure of the mechanism:

Hard seal is a seal between metal and metal, sealed ball and seat are metal. Processing accuracy and process more difficult, generally used in high pressure, usually more than 35MPa. Soft seal is a seal between metal and nonmetal, such as nylon tetrafluoroethylene, the same standard is made.

2. sealing material:

Elastic soft seal gate valve and hard seal gate valve is the sealing material of the seat, the hard seal is the valve seat material precision machining to ensure that with the spool (ball) with the accuracy, generally have stainless steel and copper. Soft seal refers to the sealing material embedded in the valve seat is a non-metallic material, because the soft sealing material has a certain flexibility, so the processing accuracy requirements relative to the hard seal will be low.

3. manufacturing process

As a lot of chemical industry, the mechanical industry's working environment is more complex, many are high temperature and high pressure, medium friction resistance, corrosive. Now the technical progress, the use of a variety of materials is better, processing and other aspects can keep up with the hard seal of the ball valve has been widely promoted. In fact, the principle of hard seal ball valve and soft seal is the same, but because the seal between the metal, to take into account the hardness of the relationship between the metal, as well as working conditions, what media and so on. Generally require hardening treatment, the ball and the valve seat between the continuous grinding to reach the seal. Hard seal ball valve production cycle is long, processing more complex, hard seal ball valve is not easy.

4. the use of conditions

Soft seal general seal can be achieved very high, while the hard seal will be based on the requirements can be high or low. Soft seal requires fire protection, because at high temperatures, the soft seal material will leak, and the hard seal is not the problem. Hard seal can generally do a very high pressure, soft seal is not OK. Soft seal due to the problem of media, some occasions can not be used (such as some corrosive media). Finally, the hard seal valve is generally more expensive than the soft seal. As for the manufacturing side, the difference is not big, mainly the difference between the valve seat, soft seal is non-metallic, hard seal is metal.