Diesel engine fire pumps are mainly used in flood control and emergency municipal engineering, farmland irrigation, urban water supply and drainage, fire water supply, hydropower engineering, metallurgy, mining, petroleum, chemical and other industries, and play an important role in flood control and emergency conditions. A diesel engine fire pump is a machine that transports liquids or pressurizes liquids. It transmits the mechanical energy of the prime mover or other external energy to the liquid to increase the energy of the liquid. It is mainly used to transport liquids including water, oil, acid and alkali, emulsions, suspoemulsions and liquid metals, etc., and can also transport liquid and gas mixtures. and liquids containing suspended solids. The technical parameters to measure the performance of the pump include flow rate, suction lift, lift, shaft power, water power, efficiency, etc.; according to different working principles, it can be divided into positive displacement pumps, vane pumps and other types. Positive displacement pumps use the change in the volume of their working chambers to transfer energy; vane pumps use the interaction between rotating blades and water to transfer energy, and there are centrifugal pumps, axial flow pumps and mixed flow pumps.