In small and medium-sized towns, industrial and mining terminals, rural areas and other regions, fire engines are difficult to reach or cannot arrive in a timely manner due to traffic restrictions. Equipped with fire hoses and fire nozzles, mobile fire pumps are suitable for fighting general material fires and are not restricted by traffic, power supply or regional conditions. At present, the two main types commonly used are portable mobile fire pumps and floating fire pumps. A portable mobile fire pump generally consists of a gasoline engine, a single-stage centrifugal fire pump, a priming device, and accessories such as a portable frame.
Portable mobile fire pumps are divided into four-stroke and two-stroke types according to the different working cycles of gasoline engines. A four-stroke gasoline engine completes one working cycle after two rotations, while a two-stroke gasoline engine completes one working cycle per rotation. Due to its relatively complete valve train, the four-stroke gasoline engine ensures high cylinder volumetric efficiency, good combustion process and favorable economic performance. The four-stroke gasoline engine is equipped with a dedicated lubrication system, which provides good lubrication conditions for components and ensures a long service life. Meanwhile, four-stroke gasoline engines do not require mixed oil, making them convenient to use. At present, four-stroke gasoline engines have been widely used in portable mobile pumps, such as BJ15, BJ10A, etc.
Two-stroke gasoline engines have no valve train or dedicated lubrication system, but they feature simple structure, small size, high power and light weight. These advantages make the overall portable pump small in size, light in weight and good in mobility when applied to portable pumps, so they are also widely used. However, two-stroke gasoline engines have low cylinder volumetric efficiency, and part of the unburned fresh mixture is discharged during the intake process, resulting in poor economic performance. In addition, two-stroke gasoline engines require mixed oil of gasoline and lubricating oil. High-power portable pumps such as BJ25D and BJ22 mostly adopt two-stroke gasoline engines.
Portable mobile fire pumps can also be divided into single-cylinder and twin-cylinder types according to the number of engine cylinders. For example, BJ7, BJ331 and BJ10A are all single-cylinder engines, while BJ20, BJ22 and BJ25 are twin-cylinder engines.
According to the rated maximum power of the engine, they are classified into 7 horsepower (hp), 9 hp, 11 hp, 15 hp, 20 hp, 22 hp, 25 hp and other types. At present, the 46 hp high-power fire pump developed by our company has filled the domestic gap and is the optimal alternative to imported products.
