PROCEDURE ESTABLISHING START OF CAVITATION IN ADJUSTING VALVES ( VARIANTS ) Russian patent published in 2003 - IPC

FIELD: hydraulics. SUBSTANCE: invention is meant for use in development of valves and hydraulic fittings of various assignment, for study of hydraulic characteristics of various local resistance. Procedure establishing start of cavitation in adjusting valve consists in measurement of medium pressure across valve inlet and outlet with fixed position of gate and change of pressure differential across it. Measurements are conducted under constant values of medium pressure across inlet to valve with determination of vibration characteristics of valve in function of pressure differential across it under hydrodynamic and cavitation modes. Corresponding critical pressure differential across valve is registered by coordinate of deviation of the latter from one another. Actual value of cavitation coefficient is established by critical pressure differential and values of pressure across valve inlet and saturated vapors of liquid at temperature of flow. Second variant of determination of actual cavitation coefficient repeats all stages of first variant with the exception of use of level of acoustic noise of valve instead of vibration characteristics. Specified procedures are simple for valves in various nominal bores and of structural implementation if they work in any range of change of Reynolds numbers and good for development of cavitation-free valves. EFFECT: development of cavitation-free valves. 2 cl, 3 dwg