INCREASING ENERGY EFFICIENCY AND FLOW RATE REGULARITY IN FACILITIES, MACHINERY AND EQUIPMENT PROVIDED WITH HIGH OPERATING PRESSURE AND LOW FLOW RATE HYDRAULIC SYSTEMS.

There are plenty of facilities, machinery and equipment, either stationary or mobile, which require hydraulic operating power, generated by low-flow pumping systems at high pressures. Such systems can be met in stationary applications, in which energy efficiency is important, while the pulsating nature of flow does not disturb, and also in dynamic applications, in which both energy efficiency and flow rate regularity are important. The first category of applications includes: static pressure tests on deepwater drilling pipes, ovens, tanks and pressure vessels, railway and road tankers; drive of the clamping devices of cutting machines, in which the operations are performed at different clamping pressure rates on the semi-finished product, and these rates must be steady throughout the duration of each operation, and so on. The second category of applications includes: drive of hydraulic cylinders, with two working speeds on the active stroke, for press machines; drive of hydraulic cylinders, at low and uniform travel speeds, coupled to high loads; cleaning and cutting parts by high-pressure water jet, mixed with abrasive material; applications of mobile hydraulics in the drive systems of construction machinery; drive of hydraulic tools, and so on. Hydraulic pressure intensifiers solve the issue of energy efficiency of high pressure generators at low flow rates, but do not handle the issue of flow regularity. Hydraulic intensifiers, supplied with high input flow rates at low pressures, provide pulsating low output flow rates, at high pressures. Even small flow pulsation found in double action hydraulic intensifiers negatively influences the uniformity of the hydraulic cylinder travel speed. High pressure hydrostatic pumps can deliver low and relatively uniform flow rates at high pressures, but they are expensive and have high energy consumption. What we propose, for dynamic applications, is a modular pumping system, consisting of a low pressure pump, which supplies three hydraulic pressure intensifiers that differ in working phase, and one of these intensifiers is constantly in the compression phase. What we demonstrate, by numerical simulation in AMESim, is that the proposed pumping system simultaneously solves the issues of energy efficiency and flow regularity. [ABSTRACT FROM AUTHOR]