The Optimization for Selection of Pressure Hose Diameter for Water jet Cleaner

　　The hose of high-pressure waterjet cleaner was used for transmitting high pressure water liquid from the hydraulic pump to the nozzle. In the existing handbooks and textbooks, the hose selection basis was the velocity of fluid flow in the pipes, and calculated hose diameter was bigger than actual one. In order to calculate the reasonable size of the hose diameter, this paper pointed out that efficiency rate of the pressure transmission in pipe should be the selection basis. The paper gave 4 examples, illustrated the details of design and actual use, and efficiency ratio value 95% was given as selection criteria. Compared to the original design method, nozzle force percentage value is not less than 97.5%. This paper provided a kind of theoretical guide for detailed evaluating hose size of the high pressure waterjet cleaner.