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As an employee and later a distributor of Worthington pumps, David Orlowski saw his share of bearings fail, normally because of the failure of the rubber lip seals that protected them. So he tinkered and, in 1977, was awarded a patent for the world’s first “bearing isolator,” a term he coined. As a compound labyrinth seal, it used centrifugal force to keep contaminants out and the bearings’ lubricant in. That same year he founded Inpro/Seal Co. (www.inpro-seal.com), Rock Island, Ill.
“Before the bearing isolator was invented, end users had to contend with sealing methods that did not adequately protect bearings,” recalls Orlowski. “Contact seals, fibrous packing, flingers, lip seals, simple labyrinth seals and other devices simply did not eliminate the root cause of the equipment failure: contamination entering the bearing environment and the loss of lubricant.”
A non-contacting labyrinth seal, the bearing isolator, gave process plants the possibility of permanent bearing protection and eliminated the need for continual maintenance. Comprised of a unitized rotor and stator that do not contact each other, the unit does not consume energy, never wears out and can be used over and over for many years, Orlowski claims.
While it ultimately took a little more tinkering, the final product was installed at a Grain Processing Corp. plant in Muscatine, Iowa, in 1975. “Corn processing needs to keep the equipment clean because the carbohydrates and mash would accumulate around the pump and would set up overnight,” Orlowski says. “Their solution was to blast it with a fire hose on a daily basis. The fire hose-down was something we thought we would be able to withstand with the new labyrinth seal.” The first seals worked well for decades, and GPC remains one of Inpro/Seal’s best customers.
Protected bearings have proven to run 150,000 hours (17 years) or more, eliminating the need for costly maintenance and repair. “[Our product’s] closest competitor, the contact seal, carries an unpredictable service life with a 100 percent failure rate,” he says.
While the bearing isolator has saved the life of many bearings in the food industry, Inpro/Seal salespeople were bringing back to the office other unmet needs of their customers. One was for a shaft sealing system, one that would allow some rotating shaft movement – angular, radial, axial – while providing alignment control with minimal or no contact. The problem was common on mixers, blenders, agitators, fans, classifiers and other machines.
The result was the Air Mizer, which relied on air pressure, rather than traditional packing, to control shaft movement while maintaining a seal that keeps liquids, powders and bulk solids in while sealing contaminants out. The Air Mizer was first introduced in 1999.
Just last year, another evolutionary product was added. Using the same concept of noncontact shaft control, water was used as the sealant in the Water Mizer. This time the shaft floats on a water barrier, which provides unlimited axial movement without any stress on the product. A half-inch water line connection attached to a regulator maintains pressure. Without any moving parts, the seal attains zero contact, zero wear and zero frictional drag.