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Harvest Technologies, a company dedicated to the development of unique technologies that harness components naturally found in the body to accelerate the normal healing process, uses iglide ® G300 bearings from igus ® Inc.

A plain bearing was being used in an automatic decanting centrifuge, which is a medical device that separates components of a patient's blood and concentrates those components for further use during surgery. Swinging buckets called trunnions, installed on a rotating rotor automatically separate various blood proteins. The buckets swing under centrifugation to align themselves with the forces.

Early designs used a metal bearing and stainless steel shaft. The bearings would gall and bind, creating a squeaking noise. This caused undesirable ambient conditions particularly because this is used in a medical environment where minimal noise and disruption is paramount. The noise was also indicative of future mechanical problems.

The immediate solution was to lubricate the bearings with oil. The company had to ship pen-sized lubricating tubes to all existing customers along with instructions on how to apply the lubricant to alleviate the problem. This was a significant expense and it solved one problem, but created new ones. The process was messy and the oil attracted dust and dirt to the axle area.

The permanent, ideal solution was to replace the metal bearings with iglide G300 plastic bearings. Immediately, costs were significantly reduced. The iglide bearings only require standard machining tolerances, while the metal required precise machining and reaming. Iglide also provides a lateral bearing surface in addition to the rotational.

Harvest Technologies was able to reduce costs by 93% and assembly time has been cut by 10 minutes. Maintenance, which had to be grudgingly performed by the customer, is also completely eliminated.

"The hidden cost was the biggest, the fact that we no longer had customers calling to say that their machine was making a weird noise was invaluable” said Paul McGovern, Senior Mechanical Engineer, Harvest Technologies. “Iglide bearings are a design engineer’s dream component: They solved a problem and they cost less!"