Role Threaded Anchor Bolts
The F1554 Specification calls for Anchor Bolts to be Rolled, Cut, or Ground at the option of the manufacturer. Anchor Bolt Express rolls all of our threads. Thread rolling uses hydraulic force at high pressure to form the threads from undersized material resulting in lower prices for our customers by eliminating waste material, as well as creating more accurate threads.
One major mistake people often make when they are measuring anchor bolts is to measure the shaft of the anchor bolt instead of the threads when checking their size. The threads should be measured when checking size as the body diameter with fall somewhere between the major and minor diameter of the threads. See the table below for the minimum body diameters for each thread diameter.
Advantages of Roll Threading
- Cost Savings - Rolled threads are made from undersized material that is between the major and minor diameters of the thread. This allows us to keep prices lower compared to using full size material. Roll threading is also faster allowing us to pass on labor savings to our customers.
- Strength - Rolled threads maintain grain structure increasing shear and tensile strength.
- Finish - Whereas cut threads can be sharp, contain cut marks, and be inconsistent; rolled threads result in smoother threads creating a better mating and safer handling.
- Accuracy - Thread rolling can maintain tolerances and consistency longer and better that cut threading.
| Minimum Body Diameter | ||||
| Nominal Diameter | Threads/in. | Body Diameter | ||
| Rolled Threads | Cut Threads | |||
| Class 1A | Class 2A | Class 1A & 2A | ||
| 1/2" | 13 UNC | 0.4411 | 0.4435 | 0.4822 |
| 5/8" | 11 UNC | 0.5561 | 0.5589 | 0.6052 |
| 3/4" | 10 UNC | 0.6744 | 0.6773 | 0.7288 |
| 7/8" | 9 UNC | 0.7914 | 0.7946 | 0.8523 |
| 1" | 8 UNC | 0.9067 | 0.9100 | 0.9755 |
| 1-1/8" | 7 UNC | 1.0191 | 1.0228 | 1.0982 |
| 1-1/4" | 7 UNC | 1.1439 | 1.1476 | 1.2232 |
| 1-1/2" | 6 UNC | 1.3772 | 1.3812 | 1.4703 |
| 1-3/4" | 5 UNC | 1.6040 | 1.6085 | 1.7165 |
| 2" | 4-1/2 UNC | 1.8385 | 1.8433 | 1.9641 |
| 2-1/4" | 4-1/2 UNC | 2.0882 | 2.0931 | 2.2141 |
| 2-1/2" | 4 UNC | 2.3190 | 2.3241 | 2.4612 |
| 2-3/4" | 4 UNC | 2.5686 | 2.5739 | 2.7111 |
| 3" | 4 UNC | 2.8183 | 2.8237 | 2.9611 |