F+W Proportioner is purely mechanicalsystem consist water motor ① and piston pump fire② , Fire water go throughwater motor ①, water motor①, rotating and drive the piston pump② , piston pump ②,draws the foam concentrate and pressurized, then inject into the outlet of thewater motor① . Both water motor and piston pump are positive displacement fluidmachinery, In theory the flow rate is proportional to the speed, so as long asthe displacement of the water motor① and piston pump② meet the requirement ofthe proportioning rate, then accurate proportioning rate can be achieved, theapplicable flow rate range depends on the difference between the theoreticaland actual displacement.

3-way Ball Valve"proportioning/Returning" is in the proportioning position understandard working Condition, when remote injection or proportioning rate testingis required, it is in the returning position,

Ball valve④ normally closed, after eachuse, the ball valve opened to clean the piston pump ② and related pipe components.