This book brings out the solution to various complex technical problems of mechanical, tribology and engineering sciences concerning tribological studies in lubricants and additives including effect of electric current and influence of magnetic flux density on bearing surfaces. It also studies diagnosis and investigations of such cases those are closely associated with the significance of tribology in multifold applications. SALIENT FEATURES: 1.Different investigations, their analysis and solutions details, those are unique in nature. 2.Premature failure of bearings due to various unforeseen causes. 3.Details of theoretical and experimental analysis of magnetic flux density distribution as a diagnostic tool for critical failures of bearings. 4.Failure of bearings under localized electrical currents. 5.Causes of shaft voltages. 6.Life estimation of turbine oils, besides a non-conventional integral approach for testing of lubricating oils and effect of nano additives on lubricants. 7.Tribological studies causing bearing failures under the effect of electrical currents.