Brass water valves are also called gate valves. Before a brass water valve can be sold, it is pressure tested at the factory. These valves are die cast and most have iron-handled wheels. All gate valves have iron threaded on the inside on both ends. Pressure relief valves are valves used to prevent excessive pressure.
Model suitable to reduce pressure,especially for domestic use in flat or single house.
Pressure reducing of water supply in high building;industrial engineering and so on.