Nitrile-butadiene rubber (NBR) and another polymer with an excellent self-lubricating property are blended to develop a new kind of polymer used for water-lubricated stern bearings. The tribological performance of the new Polymer Blend of NBR (PBN), with the comparison of a rubber common used for most stern bearings, was studied using a stern bearing test rig of SSB-100. The results showed that...

in the current study, an effort is made to determine three dimensional bearing capacity of rectangular foundations using discrete element method. the soil mass is modeled as discrete blocks connected with winkler springs. different factors affect the geometry of failure surface. six independent angles are used to define the failure surface. by trial and error, the optimum shape of failure surfa...

The paper highlights the results of anti-friction and anti-wear tests samples lubricating media containing a layered friction modifier - molybdenum diselenide. main variable test conditions are load on samples, volume concentration in oil, preliminary storage time composition before testing. evaluation criteria mass wear intensity, coefficient. Each eight cycles was implemented tribotechnical i...

Abstract In this work, we proposed a method for coating the whole surfaces of bearing balls uniformly by carbon film with rotatable ball clamp. We studied carbon/carbon friction self-designed current-carrying test system. A notable and instant force drop 28% significant wear alleviation were found when currents applied. By using TEM-, SEM-, EDS-analysis, special stacks mixture large particles o...

The present study aimed to assess the effect of replacing copper as a multi-functional ingredient in the brake pad material with potassium titanate platelet (PTP) and a particular type of ceramic fiber (CF) copper-free composite. Chase dynamometer tests were conducted to compare a brake padchr('39')s tribological behavior when PTP and CF are added to the composition with that of the copper-bear...

Friction between contacting surfaces of metal materials restricts the application of mechanical support in the high-precision inertial device of a rotational gyroscope. Instead, a diskor ring-shaped rotor is electrostatically or magnetically suspended. However, stability of the rotor suspension restricts further improvement of the measurement precision. In the developed rotational gyroscope, a ...