Coupling foam water supply equipment and foam fire fighting truck

The invention provides coupling foam water supply equipment, and relates to the technical field of fire engineering. The coupling foam water supply equipment comprises a centrifugal pump, a foam liquid storage tank, a Venturi tube, a return pipeline and a foam guide pipe; the inlet end of the backflow pipeline communicates with a water outlet of the centrifugal pump, and the outlet end of the backflow pipeline communicates with a water inlet of the centrifugal pump. The venturi tube is arranged in the return pipeline, and a medium sequentially flows through an inlet and an outlet of the venturi tube when flowing to a water inlet of the centrifugal pump from a water outlet of the centrifugal pump through the return pipeline; and two ends of the foam leading pipe are respectively communicated with the foam liquid storage tank and a low-pressure port of the Venturi tube. According to the coupling foam water supply equipment, the mixing process of the water flow and the foam stock solution is optimally designed t