Stainless steel hard seal butterfly valve with three eccentric seal structure, seat and butterfly plate almost no wear, with the more the more tight the tight seal function. 2, the sealing ring made of stainless steel, with a metal hard seal and elastic seal of the double advantages, both in the case of low temperature and high temperature, have excellent sealing performance, with corrosion resistance, long service life and so on. 3, disc plate sealing surface using cobalt-based cemented carbide, sealing surface wear, long service life. 4, large-size butterfly plate with a fixed structure, high strength, over flow area, flow resistance is small. 5, the valve has a two-way sealing function, the installation is not subject to the flow of media restrictions, nor the impact of space, can be installed in any direction. 6, the drive can be multi-station (rotating 90 ° or 180 °) to install, easy to use.