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A Closer Look at Air Gap Eccentricity

by Douglas E. Swinskey & Peter M. Bechard

The first step in evaluating test data is understanding the relationship to the circuit's Fault Zones and how abnormalities in a specific Fault Zone affect the performance of the motor. The six Fault Zones (Power Quality, Power Circuit, Stator, Insulation, Rotor, and Air Gap) are derived from the most common electrically related motor failures in industrial environments. The Air Gap Fault Zone describes the measurable distance between the rotor and stator within the motor. Air gap eccentricity is a condition that occurs when a non-uniformity in the air gap between the rotor and stator exists.


A Tough Diagnosis - The Saga of the Never Ending Problem

by Greg Davison

You are often told that there is never just one problem with a machine. My very first vibration class taught me that a phase and magnitude vector was a combination of all the vibration from all of the forces acting upon the machine. Likewise, a spectrum also contains all of the frequencies from all of the forces acting upon a machine. So, it is never just imbalance, or just misalignment. It is always some combination of many forcing frequencies. This is precisely why wall charts and cookie cutter solutions do not always work. What follows is a story of multiple problems of mythical proportions.

One Out of Many…Pointing the Whole Organization in the Same Direction

By: Dr. Peter G. Martin

Although huge quantities of technology and intellectual property have been invested into the efficient and effective operation of industrial plants over the past century, many plants are still not operating to full potential. At least part of the reason for this has been the lack of focus on the value that the human assets can generate given a supportive, collaborative and empowering environment in which to perform. Mobilizing the valuable human assets to approach their full performance potential has been proven to result in a new operational paradigm which maximizes the business performance through all plant assets. This new paradigm is labeled "asset performance management".

Infrared Windows Open the Door to Savings

A Study of a Positive, and Growing, Return on Investment by Martin Robinson

A paper mill in South Carolina had a very successful infrared inspection program that management wanted to expand. However, the requirements of NFPA 70E were causing them to re-think their strategy since inspections of energized equipment was becoming more restrictive, more time consuming and more costly. Furthermore, 8% of the mill's applications had never been surveyed due to either switched interlocks (which automatically deenergize the equipment upon opening, thereby preventing access to energized components), or to incident energy calculations in excess of 100 cal/cm2 on certain equipment (which exceeds personal protective equipment [PPE] ratings, and would place personnel in extreme danger and open the company to OSHA fines).


Building A Lubrication Program - By Using the Five Rights, You Won’t Go Wrong

by Ray Thibault, CLS, OMA I & II

This article will examine the use of the five rights of lubrication - which are Right Type, Right Quality, Right Amount, Right Place and Right Time - all of which are important in the development of a highly effective lubrication program. Many companies fail to realize the importance of lubrication and the application of these five basic concepts to achieve world class machinery reliability. Each will be examined in detail, along with a summary of best practices, including procedures in the selection of the optimal lubricant supplier.


Research Brings Results - Defining Mean Time Between Pump Failures

by Heinz P. Bloch, PE

In September 2008, we were contacted by a Mechanical Engineering student. He was close to completing an internship with a major U.S. oil refinery and had been asked to set up a system allowing the refinery to monitor its pump mean-time-between-failures (MTBF).