winding failure and possible causes,electric motor rewinds,illustrated guide to winding failures. Identifying the vibration problems that can occur in induction-motor drives have an added complexity due to the rotating magnetic-fields in the machine. Motor failure studies in the 1980s determined that a given population of motors had either an average failure rate of 0.0708 Failures per Unit per Year (FPU) for general industry (2) or 0.035 FPU for maintenance intensive industries such as utilities (1). When a bearing does fail, it is important to determine the exact cause so apprcipriate adiusfments can be made. High heats. There are also other factors which greatly affect the performance of electric motors such as low resistance, dirt, moisture, over-current and vibrations. Many electric motor failures are caused by bearing failures. Failure to follow these cautions may result in property damage. manufacturing and assembly operations, … thermometers, and electronic stethoscopes help spot bearings in poor operating condition. Diagnosing the root cause of a thrust bearing failure can be simple, but often is tricky. The squirrel cage induction motor's versatility and ruggedness continue to make it the workhorse of the industry, but that doesn't mean it's invincible. The first step is to isolate the problem. What else could be causing the noise?" This includes bearings greased for life in both the drive and non-drive end of the motor. Pushing it too hard for too long can cause the stator, rotor, bearings, and shaft to fail. Failures are shown here to help identify the causes of failure, so that, where possible, preventative measures may be taken. Most of them are caused by the over-heating of motor. Brownish marks may be observed parallel to the axis on a large part of the raceway or covering the entire raceway circumference. The purpose of Motor Current Signature Analysis for Bearing Fault Detection in Mechanical Systems ... Yacamini R and Smith K. (1996) Torsional vibrations in electrical induction motor drives during start-up. Electric motors should be installed very carefully and should be looked after at regular intervals. Another possibility is that the driven load is jammed, binding or mismatched. Viewed under a scanning electron microscope, a new bearing race wall has a smooth surface (Photo B). Finally, a comparison between different motors is presented. What to Look for. This chapter describes characteristics of many popular analysis approaches and, in some cases, provides procedures and examples of these techniques. eight major causes of premature engine bearing failure, along with percentage figures which indicate how often each has been found to be the prime contributor to a bearing’s destruction. Examination of th6 failure mode ohn reveals the true cause of failure. It is important to understand that equipment usually fails over time, reliability decreases and losses increase (efficiency decreases) over time prior to most catastrophic failures. Is this cause for concern? The 2Z bearings are closed by a metal shield on both sides of the bearing … The easiest course of action is to take the necessary steps during engine assembly and installation to prevent the failure from ever occurring. 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