Effect of contact pressure on the coefficient of static friction of selected elastomers on aluminium. The static friction investigations of sliding couples (elastomer on aluminium) in water have been presented in the paper. The selected polymeric materials for tribological investigations were made of thermoplastic material (PUR D44) or rubbers (NBR, EPDM, SI). The coefficient of static friction for tested materials initially increased with the increase of contact pressure. Further increasing of the pressure resulted in a decrease of the coefficient of friction.
Determination of rheological parameters of lubricants for non-contact seals. Presented study was conducted to determine the flow curve of four types of new generation greases and to approximate of three mathematical models that describe their rheological behavior. These results are required for further study of grease behavior inside the gap of the contactless seal and for develop of possible ways to prevent the phenomenon of delamination and leakage.
Modernization of servomotors using computer modeling and simulation of hydraulic systems and controls. The paper describes a classic servomotor for steam turbine valves.
Modernization of the servomotor as well as advantages of new design has been presented. The paper also presents a computer simulation of servomotor work before and after the modernization.
Influence of changing dynamic characteristics of the end floating seal on vibration state of the centrifugal compressor. There were considered the technical decisions aimed on modernization of the end floating seals for the centrifugal compressor that increased the limit of the rotor system dynamic stability and reduced the vibration levels.
Proper solution of hydraulics problems as a key for a shale gas getting. The article presents energy and ecology aspects of fossil fuel combustion. The differences between conventional and unconventional deposits of natural gas have been defined. The techniques and technologies of operating of directed boreholes as well as fracturing procedures connected with getting of gas strata deposition have been discussed. Some potential risks associated with the exploitation of shale gas have been also pointed out.
