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| A Where
options are given, all the tests under an option shall be performed.
Option A, Option B, and Option C indicates manufacturer may perform all
Option A (full-size), all Option B (machined specimen), or all Option C
tests whichever is preferred. Option A tests should be made whenever
feasible. B Tests that are not mandatory. C Special fasteners are those fasteners with special configurations including drilled heads, reduced body, etc., that are weaker than the threaded section. Special fasteners having full-size heads shall be tested as specified for studs and other bolts. |
|
| Nominal Size, in. ( D) | Coarse Threads–UNC | Fine Threads-UNF | Thread Series–8 UN | |||
| Threads/in. | Stress Area A, in.2 | Threads/in. | Stress Area A, in.2 | Threads/in. | Stress Area
A, in.2 |
|
| 1⁄4 (0.250) | 20 | 0.0318 | 28 | 0.0364 | . . . | . . . |
| 5⁄16 (0.3125) | 18 | 0.0524 | 24 | 0.0580 | . . . | . . . |
| 3⁄18 (0.375) | 16 | 0.0775 | 24 | 0.0878 | . . . | . . . |
| 7⁄16 (0.4375) | 14 | 0.1063 | 20 | 0.1187 | . . . | . . . |
| 1⁄2 (0.500) | 13 | 0.1419 | 20 | 0.1599 | . . . | . . . |
| 9⁄16 (0.5625) | 12 | 0.1820 | 18 | 0.2030 | . . . | . . . |
| 5⁄8 (0.625) | 11 | 0.2260 | 18 | 0.2560 | . . . | . . . |
| 3⁄4 (0.750) | 10 | 0.3340 | 16 | 0.3730 | . . . | . . . |
| 7⁄8 (0.875) | 9 | 0.4620 | 14 | 0.5090 | . . . | . . . |
| 1 | 8 | 0.6060 | 12 | 0.6630 | . . . | . . . |
| 1-1⁄8 (1.125) | 7 | 0.7630 | 12 | 0.8560 | 8 | 0.790 |
| 1-1⁄4 (1.250) | 7 | 0.9690 | 12 | 1.0730 | 8 | 1.000 |
| 1-3⁄8 (1.375) | 6 | 1.1550 | 12 | 1.3150 | 8 | 1.233 |
| 1-1⁄2 (1.500) | 6 | 1.4050 | 12 | 1.5810 | 8 | 1.492 |
| A Tensile stress areas are computed using the following formula: As = 0.7854(D - 0.9743/n)2 | ||||||
| where:
As = tensile stress area, in.2, D = nominal size (basic major diameter), in., n = number of threads per inch. |
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