Intelligent multi-stage forest fire pump

The intelligent multi-stage forest fire pump comprises a water supply fire pump and a plurality of relay fire pumps which are sequentially connected in series, connecting pipes are fastened to the water inlet ends of the water supply fire pump and the relay fire pumps in a threaded mode correspondingly, and drainage structures are arranged on the water inlet sides of the connecting pipes; an external cooling assembly is additionally arranged at the water outlet end of the drainage structure on the relay fire pump, the external cooling assembly comprises a long pipe, the side edge of the upper end of the long pipe is communicated with a water guide pipe, spray heads are arranged at the bottom of the water guide pipe at intervals, and the spray heads are arranged above the relay fire pump. The external cooling assembly is additionally arranged at the water outlet upper end opening of the sleeve base in the drainage structure, the temperature around the fire pump body is reduced by spraying water vapor to the fi