Shenyang Chengxin Energy-saving Equipment Manufacturing Co., Ltd. is a high-tech enterprise specialized in valves' research and development, production and sales, which is located in Shenyang economic technological development zone. The company produces more than 30 kinds of valves of different types and specifications. Main products include: high energy saving draining valves of all specifications, leak-off bellows stop-valve type A and B, the compound tree-eccentric metal hard-sealing butterfly valve, double-eccentric soft-sealing butterfly valve, valve for transformer, marine valve and so on. Among them, high energy saving draining valves of all specifications and leak-off bellows stop-valve type A and B obtained energy saving certificates issued by Economic and Trade Committee of Liaoning Province in September 5, 2003. The new type bellows stop-valve was awarded patent right in September 14, 2005 by state Intellectual Property Office of the People's Republic of China, Patent No. ZL 2004 2 0069814.2