Linear motion applications usually require bearings and guides that traditionally come in two basic cross-sectional configurations: rectangular or round. Each type of linear bearing uses recirculating balls that are configured in a loop or raceway to overcome friction. These balls must roll freely as the bearing traverses down the guide as the load exchanges between adjacent balls, resulting in smooth motion and low stresses during operation.
Recirculating ball linear bearing systems require periodic maintenance and lubrication to ensure they operate properly and do not cause damage to the ball bearings or guides. While some systems are outfitted with automated lubrication systems, other systems require periodic or regularly scheduled machine downtime so that technicians can manually lubricate the bearings with a grease gun. Insufficient lubrication can cause damage, resulting in bearing failure, the development of flat contact points in the balls or gouges in the guides, which may result in high force requirements, uneven motion or excessive noise. The likely result is refurbishment or replacement of the entire linear guide system.
The cost for improper lubrication can be significant, taking into account the labor and material costs for maintenance and repair, together with lost revenues due to production downtime. According to a major ball bearing company, 54% of bearing failures are lubrication related. In a study by the Massachusetts Institute of Technology (MIT), it was estimated approximately $240 billion is lost annually across U.S. industries due to downtime and repairs for manufacturing equipment damaged by poor lubrication. By eliminating the need to lubricate linear bearing systems, OEMs can minimize the costs and risks associated with maintenance for the end user. At the same time, costs related to the proper disposal of oil can be eliminated, and the initial expenditure for ancillary components and processes (e.g., grease lines, zerks and manifolds) can be decreased.
As an alternative to reciprocating ball linear bearings, igus® offers self-lubricating plastic bearings that virtually eliminate periodic maintenance and lubrication. Unlike rolling element bearings, these bearings slide against the guide instead of roll. They consist of a base polymer optimized with fiber reinforcement and solid lubricants to deliver smooth operation with increased load-carrying capabilities, along with increased resistance to wear and corrosion. Self-lubricating bearings operate completely dry, requiring no external oil or grease for operation, making them an ideal solution for applications requiring cleanliness, such as in labs, hospitals and food processing. The lack of oil or grease also enables self-lubricating plastic bearings to perform well in dirty environments since they do not attract dust and dirt.
igus® uses its innovative polymer material technology to develop products that provide creative solutions, such as self-lubricating linear bearings. With increasing competition in today’s manufacturing sector, companies are struggling to decrease costs while maintaining high-throughput operations on a variety of levels. Reducing maintenance times and costs, increasing efficiencies and providing simple methods to design in new technologies are only a few advantages that Igus’ self-lubricating linear bearings offer.