A test-rig for the characterization of five-pad tilting-pad journal bearings

The selection of oil-film bearings in new installations of rotating machines requires the knowledge of the bearing characteristics such as Babbitt metal temperatures, fluid-film thickness, load capacity, stiffness and damping coefficients. The theoretical evaluation and/or the experimental estimation of these parameters are mandatory in the design phase. The theoretical evaluation of all these coefficients for tilting pad journal bearings is difficult due to their complex geometry, boundary and thermal conditions and turbulent flow, whereas an experimental characterization requires suitable test rigs. The paper describes the test rig designed to this purpose and its unusual configuration with respect to other test rigs available in literature.