Material Notes:
Description: Rulon® is the Saint-Gobain trade name for their family of proprietary PTFE compounds. This family of materials offers the combination of high compressive strength, low coefficient of friction, and excellent abrasion and corrosion resistance while running without lubrication. They are used in bearing and seal applications from temperature extremes of 400°F to over 500°F with and without additional lubricants. A unique property of Rulon® is the absence of stick slip, that is, erratic low-speed motion. PTFE = polytetrafluoroethylene

488 Grade Bearing/Seal PTFE: Resistance to high operating temperatures, excellent wear resistance, and compatibility with most mating surfaces, make Rulon 488 non-lubricated dryer bearings the superior solution to the harsh operating environments of veneer dryers. Unlike other bearings, Rulon 488 is specifically designed to prevent expensive downtime caused by thermal shock. When used at extreme temperatures and under heavy loads, Rulon 488 will deform, but will not shatter. This helps to eliminate sudden failures and possible damage to other dryer components. In addition, Rulon 488 bearings last three times longer than conventional carbon bearings-providing significant cost savings in the long run. Rulon 488 bearings are also easy to install and need no maintenance, since they are self-lubricated. Turquois in color.

Suitable for environments of steam, wet, dry, vacuum type. Mating surface of steel/stainless steel Rc 25 and higher, or painted metal/porcelain surfaces. Material has electrical and thermal insulation properties. Markets for 488 grade include Aerospace & Aviation, Agricultural, Appliances, Dairy/Food/Beverage, Industrial.
Information provided by Saint Gobain Performance Products.

 

Specific Gravity, 73°F 2.25  
Tensile Strength @ Yield, 73°F 2,000 psi
Tensile Elongation (at break), 73°F 150 %
Deformation Under Load 3.0 %
Hardness, Durometer (Shore "D" scale) D-60  
Coefficient of Friction (Dry vs Steel) Dynamic 0.10 to 0.30  
Maximum Static Bearing Load (P) 1000 psi
Maximum Unlubricated No Load Bearing Velocity (V) 400 ft/minute
Maximum Limiting PV (Unlubricated) 10000 psi x ft/min.
Minimum Mating Surface Hardness B-25 (64) Rockwell (Brinnell)
Embrittlement Temperature -400 °F Min.
Continuous Service Temperature in Air 550 °F Max.
Short Term Service Temperature 600 °F Max.
Thermal Conductivity 2.6 BTU-in/(hr/ft2 °F)
Water Absorption, Immersion 24 Hours nil %
Water Absorption, Immersion Saturation nil %