The structural feature of the traditional center butterfly valve is that the valve stem axis, butterfly plate center, and body center are at the same position. The structure is simple and easy to manufacture. Common rubber-lined butterfly valves fall into this category. The disadvantage is that the butterfly plate and valve seat are always in a state of extrusion and scraping, resulting in large resistance and rapid wear.
So The center butterfly valve was modified to get the offset butterfly valve.
The offset butterfly valve greatly eliminates the unnecessary excessive extrusion and scratching between the butterfly plate and the valve seat in the concentric butterfly valve, reduces the opening resistance, reduces wear and tear, and increases the service life of the valve seat. At present, the eccentric butterfly valve has been improved twice, forming a triple eccentric butterfly valve.Triple-eccentric butterfly valves are more resistant to high temperature and high pressure environments and corrosion than traditional butterfly valve products.