Thrust washer test

Wear tests are conducted with a thrust-washer test apparatus. A sample thrust washer is mounted in an antifriction bearing equipped with a torque arm (see Fig. 3-105) [323]. The test-specimen holder is drilled to accept a thermocouple temperature probe. The raised portion of the thrust washer bears against a dry, cold-rolled, carbon-steel wear ring with a 12- to 16-microinch finish at an 18 to 22 Rockwell C scale hardness at room temperature. Each evaluation is conducted with a new wear ring that has been cleaned and weighed on an analytical balance. The bearing temperature and friction torque are continuously monitored. 

The coefficient of friction data in Table 3-7 were obtained with the thrust washer test apparatus. The test specimen is run in against the standard wear ring until 360-deg contact between the raised portion of the thrust washer and wear ring is made. Temperature of the test specimen is then allowed to stabilize at the test conditions (generally 40 psi, 50 ft/min, room temperature, and dry). After thermal equilibrium, the dynamic frictional torque generated is determined with... 

A plastic block is weight-loaded against the rim of the disk (line contact) and the wear test is usually between 20 and 30 hours. The plastic samples have dimensions that allow them to be made from plastic flex test bars that are commonly molded out of new plastics to measure their flexural properties. This test is intended to replace the thrust washer test. The ASTM test procedure does not require measurement of counterface wear, but it is always advisable to make this measurement. The disk weighs more than 3 kg, making it difficult to weigh it to measure mass change that occiured in a test Profilometry could be used. 

ASTM D 3702, Test Method for Wear Rate of Materials in Unlubricated Rubbing Contact Using a Thrust Washer Testing Machine, ASTM, West Conshohocken, PA, 1993... 

From these data an array of wear rate and wear factor can be calculated as described in Section 2.3.2. The thrust washer test generates wear information for a material based on area contact, not line or point contact as needed in some bearing applications. 

Figure 5.5 Wear against mild steel in a thrust washer test for DuPont Delrin 500 and 500CL (internally lubri Gated) medium-viscosity POM resins (nonlubricated, P = 0.04 MPa, V = 0.95 m/s) [2].

Table 5.18 Wear Resistance Data of RTP 800 Series Acetal (POM) Compounds Against Other Plastic Compounds, Determined by Thrust Washer Test PerASTM D3702 [11]...

Table 6.1 Wear Resistance Data Determined by Thrust Washer Test Per ASTM D3702 for RTP 300 Series Polycarbonate (PC) Compounds Against Various Plastics [5]...

Thrust washer testing conducted per ASTM D 3702. Wear factor [mmy(N m)] x 10. ... 

Table 8.9 Wear Resistance Data of RTP 200 Series Polyamide 66 (PA 66) Compounds Against Steel (1018 C), Determined by Thrust Washer Test Per ASTM D 3702 [19]...

Figure 12.12 Coefficient of friction versus PVfactor (per ASTM D3702 thrust washer testing at 1 m/s test speed) of Victrex WG PAEK resins [12].

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