A307
A307
ASTM A307
Grade A and B
(Mechanical Properties)
Hex bolts are available in two dimensional standards:
Hex bolts in a size range from 1/4″ thru 3/4″ in diameter
and in lengths 8 inches and shorter are often shipped from Cap-screw
stock at the Hex bolt price. However, when ordered as hex bolts there
is no guarantee that they will meet all Cap-screw requirements.
The ASTM A307 specification covers carbon steel bolts and studs ranging from 1/4″ through 4″ diameter. This is your everyday, run of the mill bolt specification often manufactured using A36 round bar. There are three grades A, B, and C* which denote tensile strength, configuration, and application. Refer to the Mechanical Properties Chart for the subtle strength differences within each grade.
A307 Grades
| A |
|
Headed bolts, threaded rods and bent bolts intended for general applications |
| B |  |
Heavy hex bolts and studs intended for flanged joints in piping systems with cast iron flanges. |
A307 Mechanical Properties
| Grade | Tensile Ksi,min | Yield,ksi,min | Elong,%,min |
|---|---|---|---|
| A | 60 min | – | 18 |
| B | 60-100 | – | 18 |
A307 Chemical Properties
| Element | Grade A | Grade B |
|---|---|---|
| Carbon, max | 0.29% | 0.29% |
| Manganese , max | 1.20% | 1.20% |
| Phosphorous, max | 0.04% | 0.04% |
| Sulfur, max | 0.05% | 0.05% |
HEX AND HEAVY HEX BOLTS
| Nominal size or basic bolt Dia. | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| E | F | G | H | Lt(Ref)* | |||||||
| Body or shoulder dia. | Width across flats | Width across Corners | Height | For bolt length <= 6 in | For bolt length > 6 in | ||||||
| Max. | Basic | Max. | Min. | Max. | Min. | Basic. | Max. | Min. | Basic | Basic | |
| 1/4 | 0.260 | 7/16 | 0.438 | 0.425 | 0.505 | 0.484 | 11/64 | 0.188 | 0.150 | 0.750 | 1.000 |
| 5/16 | 0.324 | 1/2 | 0.500 | 0.484 | 0.577 | 0.552 | 7/32 | 0.235 | 0.195 | 0.875 | 1.125 |
| 3/8 | 0.388 | 9/16 | 0.562 | 0.544 | 0.650 | 0.620 | 1/4 | 0.268 | 0.226 | 1.000 | 1.250 |
| 7/16 | 0.452 | 5/8 | 0.625 | 0.603 | 0.722 | 0.687 | 19/64 | 0.316 | 0.272 | 1.125 | 1.375 |
| 1/2 | 0.515 | 3/4 | 0.750 | 0.725 | 0.866 | 0.826 | 11/52 | 0.364 | 0.302 | 1.250 | 1.500 |
| 5/8 | 0.642 | 15/16 | 0.938 | 0.906 | 1.083 | 1.033 | 22/64 | 0.444 | 0.378 | 1.500 | 1.750 |
| 3/4 | 0.768 | 1 1⁄8 | 1.125 | 1.088 | 1.299 | 1.240 | 1/2 | 0.542 | 0.455 | 1.750 | 2.000 |
| 7/8 | 0.895 | 1 5⁄16 | 1.312 | 1.269 | 1.516 | 1.447 | 17/64 | 0.604 | 0.531 | 2.000 | 2.250 |
| 1 | 1.022 | 1 1⁄2 | 1.500 | 1.450 | 1.732 | 1.653 | 43/64 | 0.700 | 0.591 | 2.250 | 2.500 |
| 1 1⁄8 | 1.149 | 1 11⁄16 | 1.688 | 1.631 | 1.949 | 1.859 | 3/4 | 0.780 | 0.658 | 2.500 | 2.750 |
| 1 3⁄4 | 1.277 | 1 7⁄8 | 1.875 | 1.812 | 2.165 | 2.066 | 27/32 | 0.876 | 0.749 | 2.750 | 3.000 |
| 1 3⁄8 | 1.404 | 2 1⁄16 | 2.062 | 1.994 | 2.382 | 2.273 | 29/52 | 0.940 | 0.810 | 3.000 | 3.250 |
| 1 1⁄2 | 1.531 | 2 1⁄4 | 2.250 | 2.175 | 2.598 | 2.480 | 1 | 1.036 | 0.902 | 3.250 | 3.500 |
| 1 3⁄4 | 1.785 | 2 5⁄8 | 2.625 | 2.538 | 3.031 | 2.893 | 1 5⁄12 | 1.196 | 1.054 | 3.750 | 4.000 |
| 2 | 2.039 | 3 | 3.000 | 2.900 | 3.464 | 3.306 | 1 11⁄12 | 1.388 | 1.175 | 4.250 | 4.500 |
| 2 1⁄4 | 2.305 | 3 3⁄8 | 3.375 | 3.262 | 3.897 | 3.719 | 1 1⁄2 | 1.548 | 1.327 | 4.750 | 5.000 |
| 2 1⁄2 | 2.559 | 3 3⁄4 | 3.750 | 3.625 | 4.330 | 4.133 | 1 23⁄12 | 1.708 | 1.479 | 5.250 | 5.500 |
| 2 3⁄4 | 2.827 | 4 1⁄8 | 4.125 | 3.988 | 4.763 | 4.546 | 1 13⁄16 | 1.869 | 1.632 | 5.750 | 6.000 |
| 3 | 3.081 | 4 1⁄2 | 4.500 | 4.350 | 5.196 | 4.959 | 2 | 2.060 | 1.815 | 6.250 | 6.500 |
| 3 1⁄4 | 3.335 | 4 7⁄a | 4.875 | 4.712 | 5.629 | 5.372 | 2 3⁄14 | 2.251 | 1.936 | 6.750 | 7.000 |
| 3 1⁄2 | 3.589 | 5 1⁄4 | 5.250 | 5.075 | 6.062 | 5.786 | 2 3⁄14 | 2.380 | 2.057 | 7.250 | 7.500 |
| 3 3⁄4 | 3.858 | 5 5⁄8 | 5.625 | 5.437 | 6.495 | 6.198 | 2 1⁄2 | 2.572 | 2.241 | 7.750 | 8.000 |
| 4 | 4.111 | 6 | 6.000 | 5.800 | 6.928 | 6.612 | 2 13⁄16 | 2.764 | 2.424 | 8.250 | 8.500 |