The operational process of the liquid-packed ring vacuum pump used in the system of machinery milking is the subject of the research. The aim of the research is to substantiate parameters of hydraulic scheme of the vacuum-power milking unit while changing pump discharge, which is satisfied the requirements for stability supply of vacuum to the operation parts by regulating rotary rotations per minute, as well as to determine volumetric displacement of liquid-packed ring vacuum pump at the change of rotary rotations per minute. During the research, feature analysis of blade liquid-packed ring pump with offset axis of operational wheel was done. Blade pumps, which include liquid ring vacuum pumps, interact with the fluid flow provided by the blades, which drive a flow in circulation in the inner cavity. Specific character of the blade pump with offset axis of the operational wheel is periodical occurrence of the off-liquid vacuum volume between blades which are joined to central zone. The analysis results in determine the corresponding zones of the pump body: liquid suction, compression of the sealing liquid, evacuated space. These results became the base for constructing parallelogram of velocities and adjusting the placement of technological orifices. Further the hydraulic scheme of liquid-packed ring vacuum pump for the experimental milking unit was developed and its parameters were substantiated. To describe volume discharge of liquid-packed ring vacuum pump, the theory of dimension was used. The determination of pressure head of the given pump was based on the parameters of the developed hydraulic scheme. The research results in obtaining the balance equation for the discharge in suction zone of the pump. The main terms of the equation are pressure emerging in operation chamber and its inlet, mass flow rate of gas, absolute temperature in compression zone of operation chamber, supply in suction zone.
Keywords: vacuum, liquid-packed ring vacuum pump, gas-liquid mixture, between-blade space, rotor.
