Most Common Mechanisms and Reasons for Electric Motor Failures in Industry

Electric motors used in the petrochemical industry are specified and designed for a minimum of 25 years of service life and at least 5 years of uninterrupted operation for [1] induction machines and synchronous [2] machines. Original equipment manufacturer engineers are designing to meet these requirements using modern design software, the latest materials, improved manufacturing processes and better mechanical configurations and cooling techniques, the reality is that many of these motors will fail prematurely in the first years of operation. This paper discusses the most common contributing factors of medium and high voltage induction and synchronous motor failures in the petrochemical industry. These contributing factors include; design flaws, manufacturing defects, incorrect selection of motor enclosures, maintenance issues and motor protection. This paper will help end users understand the importance of the mechanisms that lead to critical motor failure and maintenance practices designed to help keep equipment in optimum condition. This paper does not discuss specific original equipment manufacturing issues; but instead focusses on general mechanisms related to early motor failures based on root cause analysis, experience history and end-user feedback.