HP Bearings
6Pages

High-performance Thermoplastic Bearings SPECIALTY DESIGNS Greene, Tweed has developed a unique range of thermoplastic bearing materials that provide excellent tribological properties. Our bearings are machined to ensure ease of assembly, protect against particle contaminants and provide cost-effective bearing solutions while withstanding temperatures up to 500°F (260°C). In addition, our bearings: • Closely control hardware interfaces • Provide minimal static and dynamic friction • Provide nonaggressive materials when running against mating hardware surfaces FEATURES & BENEFITS • Reduce build-up of tolerances with inherent reduced eccentricity and run out • High load bearing capacities allows for superior performance in demanding conditions • Low friction helps maintain consistent squeeze levels of seal components • Contaminant resistant materials prevent particles from reaching critical systems • Excellent chemical resistance prevents material degradation in harsh substances • Specialty designs to suit customers’ specifications © 2007, Greene, Tweed all rights reserved All trademarks are property of their respective owners. 04/07-GT DS-US-AS-020

Hardware Design (in inches) HARDWARE DESIGNS (TYPICAL) Rod Bearing Piston Bearing GROOVE CORNER LENGTH RADIUS (L) Z* DIA. BEARING CROSSSECTION Bearing Length +0.010/ +0.020 Bearing Length +0.010/ +0.020 Bearing Length +0.010/ +0.020 Bearing Length +0.010/ +0.020 Bearing Length +0.010/ +0.020 Bearing Length +0.010/ +0.020 Bearing Length +0.010/ +0.020 Bearing Length +0.010/ +0.020 *The clearance gap could affect other seal assemblies. Contact GT engineering for specific information. © 2007, Greene, Tweed all rights reserved All trademarks are property of their respective owners. 04/07-GT...

DESIGN CONSIDERATIONS When choosing the correct bearing material, wear, friction sirable effects at extreme temperatures. Most materials tend to requirements, load bearing capacity, temperature, pressure and expand as temperature increases and contract as temperature running velocity all must be considered. The most common choice decreases. The dimensional changes caused by thermal expansion of Arlon® grades is Arlon 1555 (035 code). Greene, Tweed’s standard will affect the performance of plastic bearings. At high temperature, recommendation for Avalon® PTFEs would be our Avalon 69, a the...

DETERMINING AXIAL LENGTH OF THE BEARING An estimated load requirement can be made using a calculation LOAD CAPACITY 1. Determine the maximum total load to be supported by the bearing. based on the failure load of the weakest dynamic member. 2. Calculate the projected bearing area by multiplying the bearing diameter by an initial axial length. Bearing load depends on factors such as diametrical tolerances, rod deflection and bearing deformation. Direct external loads and 3. Divide the total load by the projected area to arrive at the application compressive stress (also called load bearing...

EXAMPLE APPLICATION REVIEW The ability to support a load is directly proportional to the surface wear and the negative effects of frictional heat. Having oil film area. Improperly designed bearings will result in premature seal lubrication, in the absence of particle contamination, will prolong failure and possible hardware damage. Below is a calculation to the life of a dynamic load bearing system. In design, “worst case” determine the load bearing pressure that will indicate which wear conditions are considered by determining the effect of running materials are applicable. Velocity is a...

Material Designator Tables HP BEARING PART NUMBERING SYSTEM ARLON PROPRIETARY GT REINFORCED PEEK™ (POLYETHERETHERKETONE) MATERIALS designator tables found in the next column. For nonstandard designs contact GT engineering. Bearing series R = Rod P = Piston Cross Section (in.) A = 1/32 B = 1/16 C = 3/32 D = 1/8 E = 5/32 F = 3/16 G = 7/32 H = 1/4 The part numbering system requires the use of the material X X X X X Diameter (in.) to 3 decimal places x 1000 MATERIAL NAME AVALON® PROPRIETARY GT REINFORCED PTFE (POLYTETRAFLUOROETHYLENE) MATERIALS Part Numbering Example MATERIAL NAME More...