F3125 Dimensions
Since F3125 bolts are structural bolts and used in such specific applications they have some dimensional characteristics that are more strict than other grades. These dimensions include length tolerances, head dimensions, thread lengths, and length tolerances.
Structural bolts are required to have a full body diameter which limits the methods of threading the bolts in the manufacturing process. They also have shorter thread lengths than other bolts due to the nature of their application.
F3125 Available Sizes
F3125 bolts can only be ½”-1 ½” in diameter. Anything above or below this range would not follow the ASTM specification and would have to be moved to a different grade because it doesn’t exist.
A325T bolts are the exception to the standard requirements for thread lengths for A325 bolts. A325T bolts are fully threaded bolts. The threads start from the end and go to beneath the head.
F3125 Bolt Dimensions
| Bolt Diameter | D | F | C | H | T | |||||
| Body Diameter | Width Across Flats | Width Across Corners | Height | Thread Length | ||||||
| Max | Basic | Max | Min | Max | Min | Basic | Max | Min | Basic | |
| 1⁄2 | 0.515 | 7⁄8 | 0.875 | 0.85 | 1.01 | 0.969 | 5⁄16 | 0.323 | 0.302 | 1 |
| 5⁄8 | 0.642 | 11⁄16 | 1.062 | 1.031 | 1.227 | 1.175 | 25⁄64 | 0.403 | 0.378 | 1.25 |
| 3⁄4 | 0.768 | 11⁄4 | 1.25 | 1.212 | 1.443 | 1.383 | 15⁄32 | 0.483 | 0.455 | 1.38 |
| 7⁄8 | 0.895 | 17⁄16 | 1.438 | 1.394 | 1.66 | 1.589 | 35⁄64 | 0.563 | 0.531 | 1.5 |
| 1 | 1.022 | 15⁄8 | 1.625 | 1.575 | 1.876 | 1.796 | 39⁄64 | 0.627 | 0.591 | 1.75 |
| 11⁄8 | 1.149 | 113⁄16 | 1.812 | 1.756 | 2.093 | 2.002 | 11⁄16 | 0.718 | 0.658 | 2 |
| 11⁄4 | 1.277 | 2 | 2 | 1.938 | 2.309 | 2.209 | 25⁄32 | 0.813 | 0.749 | 2 |
| 13⁄8 | 1.404 | 23⁄16 | 2.188 | 2.119 | 2.526 | 2.416 | 27⁄32 | 0.878 | 0.81 | 2.25 |
| 11⁄2 | 1.531 | 23⁄8 | 2.375 | 2.3 | 2.742 | 2.622 | 15⁄16 | 0.974 | 0.902 | 2.25 |