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AN174-31
Aeronautical Standard Close Tolerance Bolt
Description
Close Tolerance Bolt
Specifications
| Country of Origin | USA |
|---|---|
| Distance From Head Largest Bearing Surface To Shank Hole Center | 2.984 inches first hole and 3.016 inches first hole |
| Drilling | Drilled Head |
| Fastener Length | Between 3.140 inches and 3.187 inches |
| Grip | 2 11/16 in |
| Grip Diameter | Between 0.2487 inches and 0.2492 inches |
| Grip Length | Between 2.672 inches and 2.704 inches |
| Hardness Rating | 26.0 rockwell c and 32.0 rockwell c |
| Head Height | Between 0.140 inches and 0.172 inches |
| Head Style | Hexagon Head |
| Head Type | Hexagon |
| Hole Configuration Style | Hexagon flats |
| Hole Diameter | 0.046 |
| Hole Quantity | 1 |
| Hole Type | Drilled |
| Industry Standards/Certification | AN174 |
| Length | 3 5/32 in |
| Material | Steel |
| Min. Tensile Strength (psi) | 125000 pounds per square inch |
| NIIN | 00-151-0323 |
| NSN | 5306-00-151-0323 |
| Shank Unthreaded Hole Diameter | 0.076 inches first hole |
| Surface Finish | 63.0 microinches bearing surface of head |
| Surface Treatment | Cadmium and chromate |
| Surface Treatment Specification | Class 3 federal specification single treatment response type 2 qq-p-416 |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series | UNF |
| Thread Series Designator | Unf (fine thread) |
| Thread Size | 0.2500-28, 1/4 |
| Weight | 0.05 lb |
| Width Between Flats | Between 0.428 inches and 0.440 inches |
Cross-reference
No interchangeable or dimensionally similar parts are on record for AN174-31. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error