MATERIAL PROPERTIES
Mechanical Properties
The mechanical properties of the filament wound back-up material are derived from the modulus of elasticity of the individual materials, and the construction. The values shown in Table 1 have been developed by using standard tests for cylindrical shapes.
| Table 1 |
Modulus (PSI) |
Ultimate Strength (PSI) |
| Axial Compression |
.8x106 |
20,000 |
| Hoop Tension |
2.7x106 |
35,000 |
| Bending |
1.5x106 |
25,000 |
| Torsion (45 degree helix angle) |
1.5x106 |
27,000 |
| Interlaminar Shear |
N/A |
3,000-5,000 |
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| Impact resistance (notch)....................................41 ft.lb./in. |
| Specific gravity..........................................................1.9 |
| Spring rate..............................................3.467x106 lb./in. |
| Ultimate strength (Sleeve Configuration)...................77,000 psi |
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NOTE: These values are applicable in -65 deg. to 250 deg. F temperature range. Bearing wall thickness was .125" in these tests; varying that dimension and/or the helical winding angle will alter these values.
Thermal Properties
Comparative values of the coefficient of expansion for the filament wound back-up material, aluminum and steel are given in table 2. The similarity between steel and filament wound back-up material in the hoop direction should be noted. A higher value for thermal expansion is realized in the axial direction because of the fiberglass filament orientation.
| Table 2 |
| Thermal Properties |
Duralon Bearing filament wound material |
Aluminum |
Steel |
| 1. Expansion (IN/IN/°F) |
| Axial Direction |
15.0x10-6 |
13.3x10-6 |
6.0x10-6 |
| Hoop Direction |
7.0x10-6 |
13.3x10-6 |
6.0x10-6 |
| |
| 2. Conductivity |
1.4 |
610-1100 |
95-185 |
| (BTU IN/FT2 °F Hr) |
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Electrical Properties
The filament wound back-up material is an electrical insulator. Its dielectric strength is about 300 volts per mil. Since the back-up material is electrically non-conducting, electrolytic or galvanic action will not take place between it and the housing or the shaft.
Chemical Properties
While Duralon bearings are typically chemical resistant, due to the wide range of exposures, specific conditions must be checked. Consult Rexnord engineers at (800) 591-0886
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