Cavitation Driven Impact in a Hydraulic Piston Pump

The occurrence of cavitation in a huge hydraulic supply system of a rolling mill which caused a severe defect in an axial piston pump is investigatet by a mathematical model of the complex suction system. It comprises wave propagation in pipes and hoses, a detailed model of the pump including each of its nine cylinders, cavitation therein, the charge and discharge processes of these cylinders with the intake duct, and several accessories influencing the hydraulic processes. Results obtained by this model are compared with on-site experiments. Countermeasures which have been proposed are evaluated by our model and their practical examination is reported. Due to the strong nonlinearity of cavitation the dynamical system shows two attracting limit sets, one with and one without cavitation. The operating conditions of the original supply system cause startup conditions which do not lie in the basin of attraction of the non-cavitating attractor.