Double Block Double Block Valve it is used in petroleum, chemical, smelting, electric power, pharmaceutical, papermaking and urban construction supporting industries. The products are strictly in accordance with GB national standards AHSI, API, DIN, BS, JIB, ISO and other international standards. Yongjian Valve mainly produces general valve, double block and double block valve, double seal guideway valve, double seal valve, double seal plug valve, flat gate valve, frictionless hard sealing flat gate valve, soft sealing flat gate valve series. Choose Yongjian, choose rest assured!