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In the exploration and mining industry, fixed and mobile machines use hydraulic drive systems (HDSs) involving hydraulic cylinders powered at high pressure rates. Such cylinders operate in heavy and high-magnitude dynamic load regimes, e.g., as part of mobile crusher buckets, excavators and mini excavators, hook-lift trailers, or mobile hydraulic jacks. In this context, there are two solutions for generating high pressure rates in HDSs: (1) by using high-pressure pumps, or (2) by using hydraulic power units consis...

Conveyance of goods and travelling of persons through the tunnels of mines or subway is done on railways of narrow or normal gauge. In interventions in case of accidents, hydraulically operated installations with small dimensions are used for lifting and rerailing the derailed rolling stock. They include hydraulic jacks (double or single acting hydraulic cylinders), supplied with low flow rates at high pressures. Feeding of hydraulic cylinders for lifting and relocating the derailed rolling stock is usually done b...

In the current context, in which the analysis of the failures by infrared thermography for the hydraulically operated machines is an increasingly widespread internationally method, starting from the year 2016, in Romania, at INOE 2000 - IHP Bucharest the first thermographic analyzes were laid made on hydraulic equipment. It is known that by maintaining normal limits of variation of the temperature and viscosity of the hydraulic oil in the actuation plants, are created the conditions of the productivity increase an...

All wind turbines have their main components (the rotor, mechanical transmission, generator) housed in a nacelle, supported by a pillar (large-sized) or a prop (small or medium-sized). Such a prop can be a guyed, a free standing, or a hydraulic one. While the former types of props require a lifting device for turbine installation and maintenance, the third type is provided with its own hydraulic system, which performs these operations. The hydraulic prop, which may have a height of 12...30 m and support wind turbi...

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 dri...