One of the most frequently misunderstood principles regarding the use of plain bearings is something known simply as the 2:1 Ratio. This paper will explore the history behind the 2:1Ratio, the mathematical theory supporting the rule, practical limitations of implementing the 2:1 Ratio and finally some simple troubleshooting steps which can be taken to overcome any problems.

In this white paper, two round shaft plain bearing technologies are explored from a tribological and application standpoint. The first technology is exemplified in the PBC Linear Simplicity bearing, which consists of a self-lubricating liner bonded to the inside of an essentially cylindrical shell. The second technology is found in the IGUS DryLin bearing based on a self-lubricating injection molded liner affixed to the inside of a similar shell.

Every linear bearing application requires a linear shaft as the inner raceway. However, many times that inner race is overlooked in the design process because it is presumed to be part of the bearing solution. The truth is that the shafting utilized in a linear application is just as critical as the bearing chosen.