Difference between hard seal and soft seal of API valve

Sealing Information:

Sealing performance refers to the valve sealing parts to prevent media leakage, it is the most important technical performance indicators of the valve.

1. Opening and closing parts and the valve seat of the two sealing surface contact;
2. Packing and valve stem and packing box of the mating and place;
3. Valve body and bonnet connection.

Usually the sealing structure of API valve is soft seal and hard seal in two forms

Hard seal: sealing both sides of the vice are metal materials or other hard materials are called “hard seal”. The sealing performance of this seal is relatively poor, but high temperature resistance, wear resistance, good mechanical properties.

Soft seal: sealing vice side of one side of the metal material, the other side is flexible non-metallic material is called “soft seal”. The sealing performance of this kind of seal is better, but not high temperature resistance, easy to wear, poor mechanical properties.