Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/339575
AGGREGATES MANAGER July 2014 12 M otors are critical to the successful opera- tion of most processes today, which means that proper motor maintenance is important to reduce the downtime and increase the productiv- ity and reliability of an operation. Proper motor maintenance consists of several key tests and procedures. e majority of motor failures can be divided into two categories: bearings and windings. erefore, we will focus on the maintenance of these two critical components. Bearing lubrication More motors fail due to bearing problems than for any other reason. e leading cause of bearing failures relates to a variety of issues surrounding lubrication. Anti-friction bearings should be relubricated on a regular basis. e lubrication schedule de- pends greatly on the motor's operating environment and service conditions. Operating conditions can be divided into three main categories, including the following: • Standard Conditions: 8 hours per day, normal or light load- ing, clean ambient air at 104°F (40°C) maximum. • Severe Conditions: 24 hours per day operation or shock loading, vibration, ambient air containing dirt or dust at 104 to 122°F (40 to 50°C). • Extreme Conditions: Heavy shock or vibration, and dust. Once the operating condition is determined, the recommend- ed relubrication schedule can be determined by using relubrica- tion intervals shown in Table 1. Most motor failures are due to bearings or windings, so ensure proper maintenance of these critical components. by John Malinowski Motor Maintenance 101 Standard Conditions Severe Conditions Extreme Conditions 4 months 2 months 1.5 months 6 months 3 months 2 months Ball bearing equipped motors Roller bearing equipped motors Relubrication intervals Table 1