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Getting your bearings
Let price and quality be your guide
There are so many bearings out there, all promising reliability and long life. But how do purchasers know they’re getting good bang for the buck? By listening carefully to production people as they explain why they prefer one type of bearing over another. It should result in a careful compromise between price and quality.
Take General Conveyor Company Ltd. of Aurora, Ont., which designs and manufactures material handling equipment and packaging machinery. A few years ago, it decided to change the type of bearing housing it used, even though the replacement product cost more.
“We started using more plastic housing bearings,” says Yury Lebkovich, senior project engineer with General Conveyor. “They’re much more expensive, but they’re stronger and more corrosion resistant.”
The company used to prefer nickel housings, which cost substantially less. “But with nickel, you sometimes get a chemical reaction that can lead to rusting,” Lebkovich explains.
Handles debris
Vendors are heeding the call for higher-quality bearings, and offering up a spate of new designs. Contamination is still a persistent problem, accounting for half of all bearing failures, according to NSK Canada.
Despite advances in sealing and lubrication, debris still manages to creep in, causing bearings to fail at only 20 per cent into their life cycle. The failure rate is even worse in harsh industrial settings. Rather than try to keep all the contaminants out, NSK decided to take a different approach with its “Tough Steel” product.
“The steel that we use in this particular bearing is better able to withstand damage caused by this type of debris,” says Dan Passero, marketing communications manager with NSK’s offices in Ann Arbor, Mich.
The company is also marketing a new EA spherical roller bearing, which has a new cage design, allowing for more rollers. “When you add more rollers…it means higher loads,” Passero says. “It also cuts down on heat. When you have less heat, you have the ability to run at higher speeds.”
A word of caution, though. No bearing is the panacea, and success always relies on proper maintenance. “If you don’t lubricate the bearing, you can have the best bearing on the market, and it doesn’t matter, it’s going to fail.”
Lubrication education
That “L” word—lubrication—translates directly into “headache” for many a production manager. It’s not easy to apply just the right amount and type of lubricant, or to stick to a proper lubrication schedule, say the team at SKF Canada Ltd., (Scarborough, Ont.), a manufacturer of bearings.
“A big energy robber is excess lubrication in the bearing,” says Frank Armellin, manager of special projects with SKF. “An actual bearing needs very little lubrication to function. But we end up pumping a lot more grease in there than is necessary, and that creates friction.”
SKF recently bought Willy Vogel AG, a lubrication company, to tackle the problem. “Their product is able to meter out exact quantities of lubricant to the friction points. So we’re able to minimize the amount of lubricant that’s applied,” says Armellin, adding the system is less wasteful and more environmental since there’s less grease to dispose of.
There are cost savings too, because according to SKF, it costs twice as much to clean up a kilogram of grease than it does to buy it. That’s why sealed bearings—which have built-in lubrication trapped inside—are so attractive.
“We’re focusing very heavily on sealed bearings and the grease that’s going in sealed bearings, as well as the seals,” adds John Melanson, who works with SKF’s Canadian application engineering team. “The bearing itself, all the metal components, is basically well-established.”
Other areas of focus include condition monitoring software, which pinpoints faults even on vibrating machinery. SKF also offers a software tool called Documented Solutions Program which uses the customer’s own production numbers to calculate possible bearing savings.
“The bearing doesn’t necessarily have to cost less in order to save them money,” says Armellin. “It can be twice as expensive, but overall, it creates a third of the cost because it lasts four times as long.”
When shopping around for bearings, don’t be surprised if there are price hikes caused by higher material costs. “It’s well understood in the industrial landscape that steel costs have just soared through the roof,” says Evan Boere, sales manager (Canada) with bearing company Timken Canada LP in Mississauga, Ont.
But price hikes are being offset by competition from Asia, Boere adds, especially since Canada isn’t applying many tariffs against Asian-based products. Armed with that information, purchasers should be able to strike a deal that makes production happy, without breaking the bank. b2b
Lisa Wichmann, editor of Purchasing b2b, may be reached at lisa.wichmann@pb2b.rogers.com; (416) 764-1491.
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