Wet system alarm valve is specially designed for fire protection system use. The valve is an important component in Wet system automatic sprinkler and fire extinguishing system and suitably applied to the system which is well and broadly used among the automatic sprinkler and fire extinguishing system.
Working principle: The valve disc switched on/off is owing to the water pressure rises up or lowers down on the piping system. When water supply pressure fluctuates by a little under normal working in non-alarming state, the by-pass balance pipe keeps the water pressure in balance above and below the valve disc, therefore maintaining the valve disc closed and avoiding alarm to happen by accident. In case of fire, the glass bulb of the close-type sprinkler will break up to spray water as a result to cause the water pressure lower down on the piping system. Owing to a differential pressure exists between the water supply pipe and the piping system on the other side, the valve disc will then open to actuate pressure switch and water flow indicator. Upon the fire protection control center receiving alarm signal, the fire protection pump will be switched on directly to spray water and extinguish fire, and then the water powered alarm starts to alarm to alert people on the spot to evacuate as soon as possible.
Application: The Wet system automatic sprinkler and fire extinguishing system is suitable for use in areas with ambient temperature higher than 4 ℃ and lower than 70℃. When ambient temperature is lower than 4 ℃, the Wet system automatic sprinkler and fire extinguishing system may also be applied. However, the pipeline behind the fire alarming valve shall be set up freeze resistant measure. When ambient temperature is higher than 70 ℃, the Wet system automatic sprinkler and fire extinguishing system shall not be applied.
A．The main valve adopts swing type straight waterway structure, with low flow rate resistance at large flowing area.
B．High quality of ductile cast iron provided materials reference for valve body and cover production which are electro-statically coated with epoxy resin powder; valve disc is made of rubber-encapsulated copper to prevent rust and jamming from occurring under normal working in non-alarming state.
C．The fire alarming pipeline is equipped with delayer which could avoid alarming to happen by accident when water supply pressure fluctuates by little to flush the valve disc open.
D．With a view to preventing the pipeline system from leaking(no more than 15L/min) or occurring large differential pressure between upper and lower chamber due to fluctuation of water supply pressure, the valve disc will open occasionally to cause alarm by accident. The valve is equipped with balancing pipe which could automatically balance the pressure between upper and lower chamber to avoid happening false alarm.
E．The valve has the characteristics of automatic tracing fire source and automatic switch-on system
F．Seawater resistance and stainless steel materials to be provided for application
