For Bruening, PdM begins with the senses by Paul V. Arnold Larry Bruening can handle a wrench with the best of them. "He can tear something apart and put it back together and we know that it's going to run.  He is extremely skilled," says his boss, Roger Schaver. But it isn't Bruening's wizardry with a hand tool or power tool that makes him so good, his work so respected. Bruening, a 59-year-old maintenance mechanic at the Wisconsin Electric power plant in Oak Creek, Wis., is renowned around the facility for his ability to sense potential danger. "I try to get to the problems before they become real problems or even catastrophies," says Bruening, MRO Today magazine's "MRO Pro" for February/March 1999.  "Call it predictive maintenance." Yes, Wisconsin Electric is big on PdM.  The Oak Creek power plant has had vibration analysis and infrared thermography tools for years.  But Bruening has carried four predictive maintenance tools of his own around the plant since joining the company in 1970.  Those are the senses of sight, hearing, smell and touch. "When you've worked somewhere as long as I have, you can tell when something isn't right," he says.  "Most of the equipment here doesn't change.  If a machine is 30 years old, next year it's going to be 31.  Because I'm familiar with the machines, I can see when there's a problem, or feel it or hear it." When he's not handling a repair job or responding to a work order, Bruening walks around the building.  Though he wears safety glasses, ear plugs and gloves, he is aware of the noises, vibration and smells coming out of the turbines, compressors, pumps, fans, mills and boilers. He'll stop and place his hand on the side of a massive piece of machinery. "Do you feel that?" he asks.  "The bearing is starting to go bad." He'll sniff around if he notices a burning smell coming from a machine. He'll peer over some pipes and get a look at a water pump. "The vertical shaft is running a little egged," he says.  "Instead of running in a true circle, you can see it moving around a little bit.  That pump has problems.  It'll have to be taken out of service and rebuilt." He'll listen as he slowly walks through the air compressor room. "With air compressors, you can hear problems," he says.  "You can hear a whistling or a knocking that is not supposed to be there." Bruening also talks to machine operators and fellow mechanics to get their viewpoint. If Bruening concludes there is a problem, he tells the person who is in charge of that area. "I feel it's my obligation to tell that person, 'You know, there's something in that compressor that doesn't sound right.  Perhaps we should take that one out,' " he says.  "If the person agrees, at the first opportune time I'll pull a couple of valves in that compressor, take a look inside and see if I can spot something." If he needs confirmation of his diagnosis, Bruening has a technician take vibration readings or an infrared image before making repairs. After he makes an alteration, or a full repair and reinstallation, Bruening returns to that piece of equipment a day later, or a week later, and checks if the problem has returned or been eliminated. "Experience and technology can go hand-in-hand," he says.  "What I like is I can go out to a machine and they'll give me a vibration reading.  I'll use that information to diagnose and repair.  Afterward, we'll take another vibration reading." This article appeared in the February/March 1999 issue of MRO Today magazine.   Copyright, 1999. Back to top Back to MRO Pro archives