PHZY (M) series tank (diaphragm) pressure air bubble ratio mixing device consists of foam tank, pressure proportional mixer, inlet pipe, outlet pipe and control valve parts and so on. When the pressure water flows through the proportional mixer of the device, the water and foam are automatically mixed in a certain proportion, and the foam mixture is outputted for the foam generator and the jetting apparatus to generate the jet air foam for extinguishing the fire. The device has both vertical and horizontal forms. Diaphragm type is characterized by a synthetic rubber bag made of rubber, foam liquid installed in the capsule and water separated, not only for general protein and fluorine protein foam solution, especially for water film foam, and after the fire Of the foam liquid can continue to use. The device has a safe and reliable, high efficiency of fire extinguishing, suitable for petrochemical enterprises, oil depots, oil terminals, airports and other important project sites.