It is a fixed type mixing device installed in the middle of the foam equipment pipe and is a bronze material mixer.
It has a structure where it sends pressurized water through a proportioner and generates pressure loss through Venturi action due to difference in flow velocity for inhaling the foam agents and mixing it with water.
Though around 40% of loss may be caused due to the Venturi tube, the structure is simple, installation cost is low, and easy to use. It can be made into 1%, 3% or 6% mixer according to the type of foam discharging device. Also, it is possible to attach a regulator to adjust the rate between 1% and 6%. When the discharging rate of the foam equipment lowers than the appropriate flow rate of a mixer, it may cause backflow due to back pressure, so a valve for preventing backflow should be installed on the inhaling line.