The correct choice of materials for the normal and reliable control valve has a very important significance.
Metal seal sanitary butterfly valve has a smaller elasticity and three-dimensional eccentric structures. Metal seal sanitary valve was originally used for high-pressure steam pipe, the price is more expensive, and it is not easy to damage the sealing surface in operation, but its manufacturing accuracy is higher, once the leakage is difficult to repair.
Thereby, the correct choice of materials on the metal seal sanitary butterfly valve has a very important significance.

The following factors need to be paid attention to before purchasing:
1) Structure shape of the butterfly valve
2) Stem bush:

Then you should know about the manufacturing process of the valve. There are five manufacturing steps of sanitary butterfly valves:
1. The standard elements are in accordance with the preparation standards of 304,316 materials, into the high-temperature intermediate frequency furnace dissolved into a liquid, but the temperature must be above 1556 degrees Celsius for operations;
2. Pouring the mold into the mold of the silica sol casting, cooling, and forming valve blanks;
3. The rough treatment or sandblasting treatment;
4. The end face and the seat are finished with the numerical control machine tool, the dimension tolerance is not more than 0.2mm;
5. For each sanitary valve inspection, to see if there are flaws, to check the standards of sanitary valves for packaging.

Stainless steel butterfly valve works with the circular disc as the opening and closing parts and with the valve stem to open, close, and adjust the fluid channel of a valve. Butterfly valves were installed in the pipe diameter direction.
In the butterfly valve body cylindrical channel, the disc-shaped butterfly plate around the axis of rotation, the rotation angle of 0 ° ~ 90 ° between the rotation to 90 °, the valve is the brand fully open state.