The Society of Maintenance and Reliability Professionals (SMRP) defines a Best Practice as, “A process, technique or innovative use of resources that has a proven record of success in providing significant improvement in cost, schedule, quality, performance, safety, environment or other measurable factors that impact the health of an organization.”
SMRP committee members and contributors are doing the industrial maintenance and asset-management profession a great service by defining terminology, building consensus standards and collecting a body of knowledge that includes Best Practices. The SMRP’s formal process of soliciting proposals, submitting them to its membership for comment, refining and agreeing upon the results, and making them available to all, is invaluable.
But defining Best Practices only gets you part of the way. To implement them, most companies and individuals need concrete examples that demonstrate how to introduce them, show the potential payoffs in both qualitative and quantitative terms, and provide inspiration for those who must overcome cultural inertia and make effective changes.
That’s what inspires the Plant Services Best Practices Awards. All that’s needed to enter is a true story about an application that fits the SMRP definition. Entries may be submitted by plant personnel, vendors, engineering firms, consultants or anyone who is familiar with the application and has permission to make that knowledge public.
Entries submitted before Sept. 1, 2008 were included in this year’s competition. We edited them as necessary for clarity, divided them into four categories, and posted them on www.PlantServices.com. Then we e-mailed the summaries to registered Plant Services readers, inviting them to vote by signing in and accessing the full stories.
The winners presented here were determined by totaling the number of readers who had accessed each entry. On the following pages you’ll find comprehensive excerpts of this year’s winning stories, as well as brief descriptions of the runners-up.
Synchronous belts save energy in HVAC
Reichhold Inc. is a global supplier to the composites and coatings industries, with 18 manufacturing facilities in 11 countries. Its facility in Durham, N.C., was spending about $80,000 per month in energy costs to operate this equipment during the summer.
A Reichhold maintenance technician approached a representative of Gates Corp., maker of industrial power transmission belt drive systems, to survey the plant for potential energy savings. The Gates representative found 21 HVAC units with 30 hp motors, 44 fume hood exhaust fans with 5 hp to 10 hp motors, and four cooling tower fan drives with 50 hp motors, all V-belt-driven.
As a first step, the Gates representative recommended turning off any equipment when it was not in use. He also recommended purchasing two preventive maintenance tools to accurately align and tension the belt drives: a laser alignment device and a sonic tension meter. When properly aligned and tensioned, a new V-belt drive will operate at 98% efficiency. Misalignment of the pulleys and improper belt tension, however, can cause efficiency to drop below 90%, wasting energy and shortening the life of the drive. By implementing these simple procedures, the Reichhold plant reduced annual energy consumption and saved $60,000 in the first year.
As a second major step, the Gates representative analyzed the existing belt drives on each piece of equipment noted above. He performed the analysis using a belt-drive selection tool called Design Flex Pro, a free software program available to design engineers, maintenance engineers and Gates distributors. In addition to designing belt drives, the program determines proper belt installation tension, calculates belt pull, determines the belt horsepower capacity, and estimates the energy savings of a synchronous belt drive over a V-belt drive.
The Reichhold facility had two 1,320-ton chillers with matching cooling towers. Each cooling tower had two fan drives fitted with six-strand V-belts. With the motors running at 100% capacity, the drives were generating 26 hp. The software analysis recommended conversion to a 14-mm Gates synchronous Poly Chain GT Carbon belt drive.
Initially, only one of the fan drives was converted so results could be compared between the existing V-belt drive and the converted synchronous belt drive. The difference in performance was substantial. With the motor operating at 100% capacity (60 Hz), the synchronous belt drive generated nearly twice the horsepower (51 hp versus 26 hp for the V-belt drive). This greater efficiency allowed the plant to operate the motor at 80% capacity (48 Hz) and still achieve the desired horsepower. With the motor drawing 20% less power to achieve the same result, energy costs were reduced. Estimated yearly cost savings for converting all four fans is $12,595, including reduced downtime and maintenance costs.
A similar approach with the HVAC drive units and rooftop exhaust fans gave estimated savings of $10,608 and $11,000 per year respectively, for a total of more than $34,000 per year in reduced energy costs. In addition, the synchronous belts will run for years without re-tensioning or replacement, saving additional downtime and maintenance costs.