Get the most from motors

An improved maintenance program for your electric motors and drives will have a great effect in achieving uptime and reliability, as well as reduced costs. Follow this step-by-step route to improve motor and drive reliability.

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By Ed Marshall, P.E.

PlantServices.com

At your plant, as at others, electric motors and drives are probably the most widely used devices, and also probably the least understood. Logically, an improved maintenance program here will have the greatest effect in achieving high uptime and reliability, as well as reduced costs.

The goal is to address the problems of electric motors and their related units to maximize uptime and reliability, keep costs to a minimum, and extend the productive life to a maximum. Here’s how to find the best ways to examine the clues to problems, develop the necessary positive pro-active procedures, implement them, and measure the results and benefits. This procedure allows you to tackle the serious problems first, on a small scale; solve them, and then expand in steps to the entire plant. It is directed toward helping the reader start a successful program now.

When you’re being pressured to reduce costs and increase productivity, the finger is pointing at you. You may have been thinking about improving maintenance department performance or you’ve already tried an improvement program, but with little real success and lots of frustration. Perhaps you’ve been to maintenance conferences and meetings. You’ve read the magazine articles, logged onto the Internet, and been impressed with the seemingly wondrous results that others appear to be achieving so easily. Now, it’s time to get a program started at your plant and obtain real results.

First, take a look at your facility and review the maintenance department with respect to electric motors and the reasons for past unsuccessful attempts at a maintenance improvement program. The possible reasons (Table 1) should serve to identify the tasks you’ll need to correct or change to achieve your goals. Each item is correctable. The most difficult task will be to change people’s attitudes and the culture from reactive to positive and proactive.

Table 1: Why programs fail
Some reasons for failure of maintenance improvement programs for electric motors.

• Inadequately defined strategy or plan
• Inadequately defined goals and objectives
• Lack of understanding of the positive advantages and benefits
• Lack of support or cooperation from Management
• Lack of understanding, support and cooperation from other departments
• Inadequate understanding of problems, failure causes and failure modes
• Inadequate preparation in methods and procedures for reliability
• Inadequate follow through and communications
• Inappropriate attitudes and inadequate culture change from reactive
• Inadequate training and teamwork
• Inadequate tools and instruments
• Unable to eliminate waste
• Undertaking too much, beyond your capabilities

Recognize that the plant is quite large, that it is a complex system with many units and many motors, each requiring attention and maintenance. Because of that complexity, the interaction between different elements and the need for culture change, the maintenance improvement effort requires careful planning and execution. Undertake the improvement program in small digestible bites, step-by-step.

Step 1 — Audit and assessment

Rather than attempting to do the entire facility, select a small portion where downtime is excessive and reliability is critical. A typical assessment period is the most recent three months. Gather relevant specifications, operating history and CMMS-based information about the motor maintenance history.

The audit and assessment gives you a good view of the plant situation. It’s probably one of the most important tasks needed to get the improvement program started. Not only will it provide a good picture of how the team is performing, but also important information on properly matched equipment, design and engineering problems, as well as the most efficient and energy-saving motors.

Step 2 — Needs and objectives

Any program for change or improvement must be based on the participants having a common understanding of needs, goals and objectives. These elements might not be easily quantifiable, but they must serve as a datum or baseline for subsequent measurement. Examples include:

• Reduced electric motor problems, failures, breakdowns, downtime
• Extended MTBF
• Reduced spare parts and materials
• Reduced product loss from equipment failure

Many other plant-specific factors are quantifiable. They can be expanded and detailed as necessary to describe each motor system element.

Step 3 — Improvement plan and strategy

Develop the improvement plan and the implementation strategy that gives the specifics for achieving motor and drive improvement. Establish a planning team of supervisors and lead persons under the leadership of the maintenance manager. Get their understanding and agreement, lay out the goals and objectives, and let them develop the elements. Divide the plan into workable sections to implement the program via small projects. A good tool for this is a road map, which delineates each task, the starting date, work assignments, anticipated completion date, elements to be completed and expectations. It becomes a working document and serves as the team’s daily assignment sheet. Foster and reward positive attitude in maintenance and operating departments. Emphasize high standards for work quality, performance and effectiveness.

Step 4 — Selecting technologies

Technology advances rapidly but it doesn’t replace the tried-and-true techniques. Inspections and preventive maintenance are still good tools. Predictive maintenance represents the proactive approach. Some of the lesser-known technologies your team might consider include:

• Forensic analysis of failed components
• Digital X-ray images of hidden flaws
• Digital high-speed photography