1. Pressure self-tightening sealing structure is adopted in the middle cavity of check valve in high-pressure power station. The higher the medium pressure, the better the sealing performance.

2. The sealing surface of disc and seat is made of cobalt-based cemented carbide overlaying welding, which is wear-resistant, high temperature-resistant, good abrasion resistance and long service life.

3. The two ends of the branch pipe are butt-welded, and the welding groove can be made according to the standard or user's requirements, so it can meet different requirements of the nozzle.