The characteristics of the hard sealing butterfly valve: 1, the disc seal is a soft and hard laminated metal sheet, with the double advantages of hard metal seal and elastic seal, both in the low temperature and high temperature conditions, have excellent sealing performance. 2, the use of three-dimensional eccentric structure, the valve seat and disc almost no friction, with the more off the tight sealing function. 3, the valve body sealing surface, the use of surfacing stainless steel, cobalt-based hard alloy, sealing surface wear-resistant, long service life. 4, unique structure, flexible operation, effort, convenience, not ring pressure high, low impact, reliable sealing performance.