Author_Institution :
EASA, St. Louis, MO
Abstract :
The new process for restoring interlaminar insulation reduces the labor required to repair damaged cores by as much as 90%. By reducing the repair time without compromising the end result, machines that might otherwise be scrapped can be economically repaired. This helps the end user by reducing repair costs and avoiding long lead times when a replacement machine is not immediately available. Treatments of brand new cores (donated by a manufacturer) indicate a modest reduction in core losses. This process should be useful to manufacturers in reducing the reject rate of new cores. The process is applicable to dc armatures (Figure 13) and would be equally effective in reducing rotor losses. When damage occurs during a motor failure, increased core losses adversely affect the insulation life as well as the operating cost unless corrective measures are taken. The new process greatly decreases both mean time to repair (MTTR) and repair cost when compared with traditional restack methods. The repairability of motors that were previously considered uneconomical to repair will benefit motor users.
Keywords :
electric motors; machine insulation; dc armatures; electric machines; electric motors; interlaminar insulation restoration; mean time to repair; motor failure; rotor losses reduction; Annealing; Core loss; Costs; Dielectrics and electrical insulation; Hysteresis; Lamination; Stator cores; Steel; Stress; Testing;
Journal_Title :
Industry Applications Magazine, IEEE
DOI :
10.1109/MIAS.2008.929347