Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
 No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
 | ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
 | ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
 | ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
 | ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
 | ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
Chemical Requirements
| Elements | Grades O, A, B, C | D | DH |
|---|---|---|---|
| Carbon | 0.55% max | 0.55% max | 0.20 – 0.55% |
| Manganese, min | — | 0.30% | 0.60% |
| Phosphorus, max | 0.12% | 0.04% | 0.04% |
| Sulfur, max | 0.15%* | 0.05% | 0.05% |
| * For grades O, A and B a sulfur content of 0.23% max is acceptable with the purchasers approval ** For grades D and DH a sulfur content of 0.05 – 0.15% is acceptable provided the manganese is 1.35% min | |||
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
ASTM A563 Nuts
The specification for ASTM A563 Nuts covers the chemical and mechanical requirements for eight grades of carbon and alloy steel nuts for general structural and mechanical uses on bolts, studs, and other externally threaded parts.
Grades
The requirements for any grade of nut may, at the supplier’s option, and with notice to the purchaser, be fulfilled by furnishing nuts of one of the stronger grades specified herein unless such substitution is barred in the inquiry and purchase order. The eight grades of carbon and alloy steel nuts covered by ASTM A563 include:
- Grade A:
- Carbon steel, hex or hvy hex
- Grade B:
- Carbon steel, hex or hvy hex
- Grade C:
- Carbon steel, quenched and tempered, hvy hex
- Grade D:
- Carbon steel, quenched and tempered, hvy hex
- Grade DH:
- Carbon steel, quenched and tempered, hvy hex
- Grade C3:
- Weathering steel, quenched and tempered, hvy hex
- Grade DH3:
- Weathering steel, quenched and tempered, hvy hex
Chemical Requirements
| Elements | Grades O, A, B, C | D | DH |
|---|---|---|---|
| Carbon | 0.55% max | 0.55% max | 0.20 – 0.55% |
| Manganese, min | — | 0.30% | 0.60% |
| Phosphorus, max | 0.12% | 0.04% | 0.04% |
| Sulfur, max | 0.15%* | 0.05% | 0.05% |
| * For grades O, A and B a sulfur content of 0.23% max is acceptable with the purchasers approval ** For grades D and DH a sulfur content of 0.05 – 0.15% is acceptable provided the manganese is 1.35% min | |||
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
ASTM A563 Nuts
The specification for ASTM A563 Nuts covers the chemical and mechanical requirements for eight grades of carbon and alloy steel nuts for general structural and mechanical uses on bolts, studs, and other externally threaded parts.
Grades
The requirements for any grade of nut may, at the supplier’s option, and with notice to the purchaser, be fulfilled by furnishing nuts of one of the stronger grades specified herein unless such substitution is barred in the inquiry and purchase order. The eight grades of carbon and alloy steel nuts covered by ASTM A563 include:
- Grade A:
- Carbon steel, hex or hvy hex
- Grade B:
- Carbon steel, hex or hvy hex
- Grade C:
- Carbon steel, quenched and tempered, hvy hex
- Grade D:
- Carbon steel, quenched and tempered, hvy hex
- Grade DH:
- Carbon steel, quenched and tempered, hvy hex
- Grade C3:
- Weathering steel, quenched and tempered, hvy hex
- Grade DH3:
- Weathering steel, quenched and tempered, hvy hex
Chemical Requirements
| Elements | Grades O, A, B, C | D | DH |
|---|---|---|---|
| Carbon | 0.55% max | 0.55% max | 0.20 – 0.55% |
| Manganese, min | — | 0.30% | 0.60% |
| Phosphorus, max | 0.12% | 0.04% | 0.04% |
| Sulfur, max | 0.15%* | 0.05% | 0.05% |
| * For grades O, A and B a sulfur content of 0.23% max is acceptable with the purchasers approval ** For grades D and DH a sulfur content of 0.05 – 0.15% is acceptable provided the manganese is 1.35% min | |||
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
Chemical Requirements
| Elements | Grades O, A, B, C | D | DH |
|---|---|---|---|
| Carbon | 0.55% max | 0.55% max | 0.20 – 0.55% |
| Manganese, min | — | 0.30% | 0.60% |
| Phosphorus, max | 0.12% | 0.04% | 0.04% |
| Sulfur, max | 0.15%* | 0.05% | 0.05% |
| * For grades O, A and B a sulfur content of 0.23% max is acceptable with the purchasers approval ** For grades D and DH a sulfur content of 0.05 – 0.15% is acceptable provided the manganese is 1.35% min | |||
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
ASTM A563 Nuts
The specification for ASTM A563 Nuts covers the chemical and mechanical requirements for eight grades of carbon and alloy steel nuts for general structural and mechanical uses on bolts, studs, and other externally threaded parts.
Grades
The requirements for any grade of nut may, at the supplier’s option, and with notice to the purchaser, be fulfilled by furnishing nuts of one of the stronger grades specified herein unless such substitution is barred in the inquiry and purchase order. The eight grades of carbon and alloy steel nuts covered by ASTM A563 include:
- Grade A:
- Carbon steel, hex or hvy hex
- Grade B:
- Carbon steel, hex or hvy hex
- Grade C:
- Carbon steel, quenched and tempered, hvy hex
- Grade D:
- Carbon steel, quenched and tempered, hvy hex
- Grade DH:
- Carbon steel, quenched and tempered, hvy hex
- Grade C3:
- Weathering steel, quenched and tempered, hvy hex
- Grade DH3:
- Weathering steel, quenched and tempered, hvy hex
Chemical Requirements
| Elements | Grades O, A, B, C | D | DH |
|---|---|---|---|
| Carbon | 0.55% max | 0.55% max | 0.20 – 0.55% |
| Manganese, min | — | 0.30% | 0.60% |
| Phosphorus, max | 0.12% | 0.04% | 0.04% |
| Sulfur, max | 0.15%* | 0.05% | 0.05% |
| * For grades O, A and B a sulfur content of 0.23% max is acceptable with the purchasers approval ** For grades D and DH a sulfur content of 0.05 – 0.15% is acceptable provided the manganese is 1.35% min | |||
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
Chemical Requirements
| Elements | Grades O, A, B, C | D | DH |
|---|---|---|---|
| Carbon | 0.55% max | 0.55% max | 0.20 – 0.55% |
| Manganese, min | — | 0.30% | 0.60% |
| Phosphorus, max | 0.12% | 0.04% | 0.04% |
| Sulfur, max | 0.15%* | 0.05% | 0.05% |
| * For grades O, A and B a sulfur content of 0.23% max is acceptable with the purchasers approval ** For grades D and DH a sulfur content of 0.05 – 0.15% is acceptable provided the manganese is 1.35% min | |||
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.
ASTM A563 Nuts
The specification for ASTM A563 Nuts covers the chemical and mechanical requirements for eight grades of carbon and alloy steel nuts for general structural and mechanical uses on bolts, studs, and other externally threaded parts.
Grades
The requirements for any grade of nut may, at the supplier’s option, and with notice to the purchaser, be fulfilled by furnishing nuts of one of the stronger grades specified herein unless such substitution is barred in the inquiry and purchase order. The eight grades of carbon and alloy steel nuts covered by ASTM A563 include:
- Grade A:
- Carbon steel, hex or hvy hex
- Grade B:
- Carbon steel, hex or hvy hex
- Grade C:
- Carbon steel, quenched and tempered, hvy hex
- Grade D:
- Carbon steel, quenched and tempered, hvy hex
- Grade DH:
- Carbon steel, quenched and tempered, hvy hex
- Grade C3:
- Weathering steel, quenched and tempered, hvy hex
- Grade DH3:
- Weathering steel, quenched and tempered, hvy hex
Chemical Requirements
| Elements | Grades O, A, B, C | D | DH |
|---|---|---|---|
| Carbon | 0.55% max | 0.55% max | 0.20 – 0.55% |
| Manganese, min | — | 0.30% | 0.60% |
| Phosphorus, max | 0.12% | 0.04% | 0.04% |
| Sulfur, max | 0.15%* | 0.05% | 0.05% |
| * For grades O, A and B a sulfur content of 0.23% max is acceptable with the purchasers approval ** For grades D and DH a sulfur content of 0.05 – 0.15% is acceptable provided the manganese is 1.35% min | |||
Mechanical Properties
| Grade | Style | Size, in. | Proof Load, ksi (Plain) | Proof Load, ksi (Galv) | Hardness, HBN |
|---|---|---|---|---|---|
| A | Hex | 1/4 – 1-1/2 | 90 | 68 | 116 – 302 |
| A | Heavy Hex | 1/4 – 4 | 100 | 75 | 116 – 302 |
| B | Heavy Hex | 1/4 – 1 | 133 | 100 | 121 – 302 |
| B | Heavy Hex | 1-1/8 – 1-1/2 | 116 | 87 | 121 – 302 |
| C / C3 | Heavy Hex | 1/4 – 4 | 144 | 144 | 143 – 352 |
| D | Heavy Hex | 1/4 – 4 | 150 | 150 | 248 – 352 |
| DH / DH3 | Heavy Hex | 1/4 – 4 | 175 | 150 | 248 – 352 |
Grade Identification Markings
| Marking | Specification | Material Type | Nominal Sizes, In. | Proof Load Stress, ksi | Hardness Rockwell (Min) | Hardness Rockwell (Max) | Note |
|---|---|---|---|---|---|---|---|
No Marking | ASTM A563 Grade O | Carbon Steel | 1/4 – 1-1/2 | 69 | B55 | C32 | 2,3 |
| No Marking | ASTM A563 Grade A | Carbon Steel | 1/4 – 1-1/2 | 90 | B68 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | 1/4 – 1 | 120 | B69 | C32 | 2,3 |
| No Marking | ASTM A563 Grade B | Carbon Steel | >1 – 1-1/2 | 105 | B69 | C32 | 2,3 |
| ASTM A563 Grade C | Carbon Steel, may be Q&T | 1/4 – 4 | 144 | B78 | C38 | 4 |
| ASTM A563 Grade C3 | Weathering Steel, may be Q&T | 1/4 – 4 | 144 | B78 | 38 | 4,6 |
| ASTM A563 Grade D | Carbon Steel, may be Q&T | 1/4 – 4 | 150 | B84 | C38 | 5 |
| ASTM A563 Grade DH | Carbon Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 5 |
| ASTM A563 Grade DH3 | Weathering Steel, Q&T | 1/4 – 4 | 175 | C24 | C38 | 4,6 |
Thread Dimensions and Overtapping Allowances
| Nominal Nut Size, in. and Pitch | Diametral Allowance, in. | Pitch Diameter, in. (Min) | Pitch Diameter, in. (Max) |
|---|---|---|---|
| 0.250 – 20 | 0.016 | 0.2335 | 0.2384 |
| 0.312 – 18 | 0.017 | 0.2934 | 0.2987 |
| 0.375 – 16 | 0.017 | 0.3514 | 0.3571 |
| 0.437 – 14 | 0.018 | 0.4091 | 0.4152 |
| 0.500 – 13 | 0.018 | 0.4680 | 0.4745 |
| 0.562 – 12 | 0.020 | 0.5284 | 0.5352 |
| 0.625 – 11 | 0.020 | 0.5860 | 0.5932 |
| 0.750 – 10 | 0.020 | 0.7050 | 0.7127 |
| 0.875 – 9 | 0.022 | 0.8248 | 0.8330 |
| 1.000 – 8 | 0.024 | 0.9428 | 0.9516 |
| 1.125 – 8 | 0.024 | 1.0678 | 1.0768 |
| 1.125 – 7 | 0.024 | 1.0562 | 1.0656 |
| 1.250 – 8 | 0.024 | 1.1928 | 1.2020 |
| 1.250 – 7 | 0.024 | 1.1812 | 1.1908 |
| 1.375 – 8 | 0.027 | 1.3208 | 1.3301 |
| 1.375 – 6 | 0.027 | 1.2937 | 1.3041 |
| 1.500 – 8 | 0.027 | 1.4458 | 1.4553 |
| 1.500 – 6 | 0.027 | 1.4187 | 1.4292 |
| 1.750 – 5 | 0.050 | 1.6701 | 1.6817 |
| 2.000 – 4.5 | 0.050 | 1.9057 | 1.9181 |
| 2.250 – 4.5 | 0.050 | 2.1557 | 2.1683 |
| 2.500 – 4 | 0.050 | 2.3876 | 2.4011 |
| 2.750 – 4 | 0.050 | 2.6376 | 2.6513 |
| 3.000 – 4 | 0.050 | 2.8876 | 2.9015 |
| 3.250 – 4 | 0.050 | 3.1376 | 3.1517 |
| 3.500 – 4 | 0.050 | 3.3876 | 3.4019 |
| 3.750 – 4 | 0.050 | 3.6376 | 3.6521 |
| 4.000 – 4 | 0.050 | 3.8876 | 3.9023 |
See Also: ASTM A563 Specifications at ASTM.org.