15/16-20 UNEF Thread Specifications
Complete dimensions for 15/16-20 UNEF (Unified National Extra Fine) thread per ASME B1.1. TPI: 20, Pitch: 0.05" (1.27 mm).
Thread Dimensions
| Designation | 15/16-20 UNEF |
| Threads Per Inch (TPI) | 20 |
| Pitch | 0.05" (1.27 mm) |
| Major Diameter | 0.9375" (23.812 mm) |
| Pitch Diameter | 0.905" (22.988 mm) |
| Minor Diameter (External) | 0.8762" (22.254 mm) |
| Minor Diameter (Internal) | 0.8834" (22.438 mm) |
| Thread Depth | 0.02706" (0.687 mm) |
| Tensile Stress Area | 0.62042 in² (400.3 mm²) |
Tap Drill Size
Recommended tap drill: 57/64" (0.8906" / 22.62 mm)
Calculated minor diameter (internal): 0.8834" (22.44 mm)
Proof Loads by SAE Grade
| Grade | Proof Stress (psi) | Tensile Strength (psi) | Proof Load (lbf) | Tensile Load (lbf) |
|---|---|---|---|---|
| Grade 2 | 33,000 | 60,000 | 20,474 | 37,225 |
| Grade 5 | 85,000 | 120,000 | 52,736 | 74,450 |
| Grade 8 | 120,000 | 150,000 | 74,450 | 93,063 |
Common Applications
- Precision assemblies
- Thin-wall tubing
- Aerospace fittings