On the development of three instructive test rigs for efficiency determination of gearboxes and fault diagnosis of joints, roller bearings and gears

This paper describes the development and evaluation of three fully instrumented instructive test-rigs to study gear box efficiency and fault diagnosis of joints, roller bearings and gears. To analyze gear box efficiency, a back-to-back test-rig with mechanically closed energy loop was developed according to the FZG principle. An electrical motor with adjustable flange coupling was integrated in the loop. The efficiency of the gears can be determined very accurately by measuring the motor power that is needed to drive the closed loop as a function of speed, locked in torque, type of oil and oil immersion depth. The second test-rig consists of a driven shaft with adjustable motor position and excited bearing house. This enables the analysis of vibrations resulting from bearing defects and shaft misalignment. Bearings with three fault patterns (ball, inner ring or outer ring defect) are analyzed under radial loading conditions and broad speed range (10-3000rpm). Moreover, single and double cardanic joints and torsionally flexible jaw type couplings are tested under radial and angular shaft misalignment. The third test rig is a closed electromechanical loop used for fault diagnosis of gear mesh defects under constant or variable torque loading. The experimental results are consistent with analytical calculations.status: publishe