Slide Bearings: Reduce Lead Time and Cost
Modest adjustments to design can result in significant economic benefits.
Note: For purposes of this discussion Teflon® is trademarked by the DuPont Corporation, Fluorogold® is trademarked by Saint-Gobain.
Slide Bearings can be specified with many different materials and substrates, but they all have a common function; Horizontal Movement. The sliding surface can be made of many different materials including;
Pure Teflon/PTFEFluorogold
Carbon Filled Teflon/PTFE
Graphite
As well, for greater compressive strength Slide Bearing assemblies are often specified with a Teflon/PTFE lower member sliding against a polished stainless steel upper member.
Each material and configuration offers some benefit over the others as well as detriments, depending on the application and operating environment. In the case of Carbon Filled Teflon/PTFE the benefits are greater compressive strength and more durability when compared to virgin Teflon/PTFE. However in cases where Carbon Filled PTFE is specified we usually suggest the architect or engineer consider Fluorogold.
The difference in composition is Carbon Fibers vs Fiberglass. Teflon infused with carbon fibers will develop more compressive strength than Fluorogold. However the difference is quite small, and the trade off can be substantial. Fluorogold is Teflon/PTFE infused with fiberglass fibers. This composition has the advantage of being self-lubricating, hence there is much lower co-efficient of friction than carbon filled sliding surfaces. To offset the increase in friction the carbon filled PTFE often includes graphite in the composition. A typical composition of 75% PTFE / 25% Carbon Fiber can be adjusted to 75% PTFE / 23% Carbon Filler / 2%Graphite. This will reduce the co-efficient of friction almost back to its original lower number, but the cost of this bearing will have increased noticeably. Added to that is the extended lead times these bearings will require.
The alternative, Fluorogold, while offering only minimally less compressive strength, is self-lubricating, is readily available, is readily available and maintains a more competitive cost structure.