2-4.5 UNC Thread Specifications
Complete dimensions for 2-4.5 UNC thread per ASME B1.1. TPI: 4.5, Pitch: 0.22222" (5.644 mm).
Thread Dimensions
| Designation | 2-4.5 UNC |
| Threads Per Inch (TPI) | 4.5 |
| Pitch | 0.22222" (5.644 mm) |
| Major Diameter | 2" (50.8 mm) |
| Pitch Diameter | 1.8557" (47.134 mm) |
| Minor Diameter (External) | 1.7274" (43.875 mm) |
| Minor Diameter (Internal) | 1.7594" (44.69 mm) |
| Thread Depth | 0.12028" (3.055 mm) |
| Tensile Stress Area | 2.47582 in² (1597.3 mm²) |
Tap Drill Size
Recommended tap drill: 1/1" (1.0" / 25.4 mm)
Calculated minor diameter (internal): 1.7594" (44.69 mm)
Proof Loads by SAE Grade
| Grade | Proof Stress (psi) | Tensile Strength (psi) | Proof Load (lbf) | Tensile Load (lbf) |
|---|---|---|---|---|
| Grade 2 | 55,000 | 74,000 | 136,170 | 183,211 |
| Grade 5 | 85,000 | 120,000 | 210,445 | 297,098 |
| Grade 8 | 120,000 | 150,000 | 297,098 | 371,373 |
Common Applications
- Industrial and structural applications
- Coarse thread applications