Current Practice in Journal Bearings

Abstract

It is advantageous from the production point of view for a manufacturer to use one standard design of journal bearing, made in a small number of standard sizes. The degree of standardization attained is, however, limited by other considerations. The economic benefits of reduction of machine dimensions and of reduction of bearing loss justify the use of bearings of small steps in diameter and of more than one length in each diameter. The operating conditions of turbine plant also affect bearing design in various ways. A bearing design which is well suited to a direct-coupled turbine generator is not suited to a journal which reverses in direction, or to a bearing where the line of application of the load swings through a large angle. Journal-bearing design is frequently influenced by the effect of the bearings on various types of rotor vibration. Manufacturers who produce a wide range of turbomachinery therefore use bearings of more than one design.