During the maintenance of engineering vehicles, we usually detect that there are some cellular cavities inside the hydraulic cylinder or at the surface of piston, piston rod. These cavities are caused by cavitation corrosion. Hydraulic cylinder cavitation could lead to burning of bearing rings and seal rings, and finally result in cylinder leak. In addition, cavitation, coupled with other types of corrosion, will greatly accelerate the corrosion of main hydraulic cylinder parts, thus significantly affecting the operation of the engineering vehicles like road rollers, loaders, and excavators.