https://www.powercastchina.com/product/sand-casting/hollow-valve-plates-cast-machined-1093.html Super duplex stainless steel has higher corrosion resistance and better mechanical properties than duplex stainless steel and is commonly used in offshore oil, water treatment and water supply systems, desalination (desalination) equipment, underwater equipment, chemical processing industries, etc. It has convenient opening and closing, rapid, labor-saving, low fluid resistance, and can be operated frequently. Simple structure, good adjustment performance, easy to install, flexible and effortless operation, manual, electric, pneumatic and hydraulic methods are available.