Sökning: "machine elements"
Visar resultat 11 - 15 av 253 avhandlingar innehållade orden machine elements.
11. Rolling bearing lubrication at low temperature
Sammanfattning : Problems connected with rolling bearings at low temperatures are high starting and running friction, concerns about the presence of a lubricating film and the degree of roller slip at low-temperature start-up. Also, questions have been raised whether the high shear stresses in a grease sheared at low temperature could cause thickener degradation. LÄS MER
12. Transient elastohydrodynamic lubrication : Effects of geometry, surface roughness, temperature, and plastic deformation
Sammanfattning : The urgent need to reduce greenhouse gas emissions in combination with an increased use of sustainable energy resources have led to immense efforts on improving energy efficiency of mechanical systems. Consequently, modern machine elements are typically lubricated with low viscosity oils and designed to endure an increasingly high power density. LÄS MER
13. Effect of water contamination on the diffused content of hydrogen under stress in AISI-52100 bearing steel
Sammanfattning : Abstract Hydrogen embrittlement is a degradation process of mechanical/tribological properties (toughness, wear etc.) of mating steel surfaces. This is caused by the presence and interaction of hydrogen with applied stresses. Therefore, it is important to quantify the hydrogen content which could be dissolved under applied stresses in steel. LÄS MER
14. Elastohydrodynamically lubricated finite line contacts operating under transient conditions
Sammanfattning : The effect of greenhouse gas emissions contributing to the global warming is today becoming an increasingly important problem worldwide and has led to increased efforts being made on improving tribological performance of interacting surfaces in mechanical systems. Due to increasingly stringent CO2regulations, a reduced fuel consumption has become a key area of interest for the automotive industry where low cost, low emission solutions are continuously developed and where low friction alternatives to machine elements currently in use are evaluated. LÄS MER
15. Monitoring of wear in elasto- hydrodynamic lubricated contacts : Running-in and failure propagation
Sammanfattning : Elasto-hydrodynamic lubricated (EHL) contacts can be found in various machine elements or systems, like rolling element bearings, cam followers or gear transmissions. The service life of these elements and systems are depending to some extent on the performance of EHL contacts. LÄS MER