A bearing service life prediction methodology and tutorial indexed to eight probable causes for bearing failure and removal are presented - including fatigue. Bearing life is probabilistic and not deterministic. Bearing manufacturers' catalogue (L10) bearing life is based on rolling-element fatigue failure, at which time 90% of a population of bearings can be reasonably expected to survive, and 10% to fail by fatigue. However, approximately 95% of all bearings are removed for cause before reaching their L10 life. A bearing failure can be defined as when the bearing is no longer fit for its intended purpose. For a single bearing, you can only predict the probability of a failure occurring at a designated time - but not the actual time to failure.

A good deal of confusion exists regarding the factors that determine an industrial electric bill. The following information is presented to help sort out the various items on which billing is based, and to offer suggestions on measures to help control and reduce electric utility bills.

Using vibration analysis to evaluate machine health has many benefits, and with advances in sensor, recording, and analysis technology, vibration analysis is now within the reach of even small organizations.

Fans, blowers and other funny loads are addressend, along with RMS Horsepower loading.

Standardized calculation methods such as ISO 6336 and DIN 3990 already exist to determine the load distributions on gears inside a planetary gearbox, but by their very universal nature, these methods offer varying results depending on the gearbox design. Double helical gears, in particular, can benefit from more specific, complex algorithms to reach a maximum level of efficiency. Double helical gears interact with the rest of the gearbox differently than helical or spur gears, and thus benefit from different analytical models outside the standardized methods. The present research project describes the algorithm to determine the load distribution of planetary gearboxes with double helical gears.

In the process of applying industrial drive products, we occasionally are misled into believing that we are applying horsepower. The real driving force is not horsepower - it is torque. This paper is developed to impart a deeper understanding of torque, its relationship to horsepower, and the types of loads we most frequently encounter.

Large hydraulic cylinders (LHCs) are integral components in the functioning of large machines in mechanically demanding, corrosive and abrasive environments, such as offshore drilling rigs. The materials utilized in these largescale hydraulic systems must deliver reliable performance throughout their expected lifecycle.

Reliability and maintenance engineers can improve uptime and save money on both long-term maintenance and downtime costs by properly diagnosing and correcting bearing vibration issues when they exceed their acceptable limits. This requires inspecting the housing as well as the liner for wear, and replacing them as a pair when the housing is worn, so that wear-in between the mating surfaces can occur.

This issue our Baldor Basics series continues with the topics of motor temperature ratings and metric motors.

Three electric motor repair facilities share best practices for utilizing copper in motor repair, and recommending new motors to replace older, less-efficient motors