Screw Gate Double Way 1.Simple structure 2.Flexible manipulation 3.Light ... its principle field in a vigorous development whose products cover valves of varieties ,envroment protection equipment ,non-standard metallurgical ... and temperature-resistance ,water butterfly valves,various dust valves,safety valves,slurr valves ,diaphragm valves ,check valves,and gate valves. The nominal diameter is DN40-- ...