Methods to Avoid Electrical Runout: Copyright Material IEEE, Paper No. PCIC-2018-17

摘要

The Runout of a shaft is defined as the deviation of the measured surface from an ideal circle rotating around its rotational axis. The total runout can be split into two main components: the mechanical and the electrical runout. The electrical runout depends on the metallurgical state of the shaft which can only be altered to a certain degree after the forging and heat treatment processes are finished. Especially large shafts for electric motors are prone for high electrical runout, because material imperfections are moved to the center of the shaft by the forging process. As there is an unfavorable ratio between bearing diameter and the largest diameter of the shaft, these imperfections will be in the area of the new shaft surface after machining. Statistics have proven that material inhomogeneity generating an electrical runout occurs in almost all kinds of steel. This paper will provide some information about how to eliminate uncertain material properties causing the electrical runout. One measure will be presented in detail including test results.