Full definition
Formation and violent collapse of vapor bubbles in a liquid when local pressure drops below the fluid vapor pressure. In hydraulic pumps causes erosion of tracks and gears, noise (crackling), vibration, and reduced volumetric efficiency. Causes: excessively long suction line, clogged suction filter, excessive oil viscosity. Prevention: ensure available NPSH > required NPSH, use ISO VG 32-46 oil at operating temperature.