The results of cvt hydraulic block tests. The paper deals with the original test-bench results of CVT7 from Jatco. Characteristics of pressure responsible for tensing the pushbelt and changing the ratio have been presented. The described test results take into account interfering factors such as different oil temperature, variable rotational speed of supply pump, and various supply pressure as well.
Keywords: CVT, control pressure, temperature influence
Possibility of using the water high-pressure technology for development of rescue tunnels. The problem of hydraulic cutting of rescue tunnels to enable rescuers reaching the workers entrapped in mine underground roadway is presented. Technology of development of rescue tunnels by hydraulic drilling of boreholes and their directional cutting with use of nozzles fed with mixture of water and abrasives is discussed.
Keywords: mining industry, rescue operations, development of tunnels, hydraulic cutting
Research on model cooperation of the radial sealing ring with the shaft end. The article discusses the problems associated with the use of radial sealing rings in bearing bodies of work rolls. In the laboratory, temperature measurements of the sealing ring and a pivot with thermal image camera were carried out. The test results of elements made of steel or porous bronze were presented.
Keywords: thermal image camera, temperature, shaft end, rolling bearings
Application of new materials in hydraulic elements and systems. The paper presents the current results of work aimed at the application of new materials in the design of hydraulic components and systems. The design, the manufacture and the tests of a fully composite hydraulic cylinder have been presented. The use of modern materials like elastomers in the vibration isolation of hydraulic components, especially microvalves has been discussed.
Keywords: microhydraulics, composite, hydraulic cylinder
Tribological carbon based coatings with advanced microstructure. The paper describes vacuum deposition techniques like PVD of thin tribological coatings. Analysis of the possible enhancement of mechanical and tribological properties of hydrogenated carbon coatings a-C:H has been presented. The authors discussed the test results of hardness, fracture resistance, and scratching.
Keywords: PVD techniques, hardness, fracture resistance, scratch tests
Evaluation of the influence of external vibrations on tightness of the valve, analysis of its own vibrations. The article presents a study of the free vibration of the gate valve DN25. Part-own vibrations of valve caused by the flowing medium as well as vibrations caused by the flowing medium and an additional external vibrations induced by an inductor were measured. Leakage was measured before and after the operation of the valve as well. The recorded vibration spectra were compared with each other and assessed their influence on the seal of the valve.
Keywords: gate valve, vibrations, tightness, leakage measurement
New design types of pump impellers operating in the range of extremely low specific speed. The paper describes the new and an innovative design of pump impellers, operating in the range of extremely low specific speed. The design and working principles were presented. The results at the test rig were presented in comparison with commonly known pump impellers.
Keywords: rapid prototyping, experimental test, pump impeller
Hydraulic system – machine or partly completed machine? The paper presents two inducted with the Machinery Directive concepts: a machinery and partly completed machine. The author discussed basic security requirements for hydraulic drives. The different procedures have been compared with selected examples of hydraulic systems.
Keywords: Machinery Directive, security requirements, hydraulic components
Diagnostics of injection molding machines using ultrasound detection and vibroacoustics. The paper presents a problem of diagnostics for injection molding machines, especially for selected elements of hydraulic systems. A data set were store and studied after diagnostic measurement procedure with an ultrasound detector and industry accelerometer. It is possible to analyze characteristic of work of the hydraulic cylinder and pump subsystem.
Keywords: vibrations, hydraulic cylinder, hydraulic pump
Model and simulation of the controllable seat suspension system of a working vehicle. The paper presents operation of a magnetorheological active damper with a PID controller in the construction of a seat in a working vehicle. The process of simulation research has been described and the obtained results have been referred to the previously designed passive system of vibroisolation. The bio-mechanical model of a human in a sitting position was taken into account.
Keywords: PID controller, active damping, magnetorheological fluid
