How does a foam proportioner work?

Proportioning systems, also called proportioners, are installed in fire extinguishing systems or available as portable systems for firefighting. Many fire scenarios require foam for effective extinguishing. To generate such foam, a foam agent must be mixed into the extinguishing water flow precisely and by means of a proportioning system. Our new demo stand makes it easy to explain the functioning principle of a foam proportioner.

Our new demo stand is a miniature of a warehouse equipped with a proportioner, a monitor and a sprinkler system.

• The proportioner consists of a proportioning pump and a water motor. When the extinguishing water pump is switched on, the water flows through the water motor of the proportioner, prompting it to rotate. This way, the water motor in turn drives the proportioning pump.
• The water flow rate through the water motor is controlled via the valves to the sprinklers or the fire monitor.
• The volumetric flow meter shows the current water flow rate passing through the water motor.
• The proportioning pump sucks in the foam agent, doses it and injects it into the extinguishing water pipework.

A ball valve can be used to switch between actual injection of the foam agent into the extinguishing water and returning it into an unpressurized foam agent tank. This is how to test the proportioning rate, while producing no foam or premix.

FireDos proportioners are easy to operate. The purely mechanical functioning principle is also highly reliable and provides maximum safety.