In addition to the the indicated grade marking, all grades included in this table must be marked for manufacturer identification. While hex heads are shown, grade markings apply equally to products with other head configurations.
Grade Identification Marking | Specification | Material | Nominal Size (inch) |
Proof Load Stress (ksi) |
Tensile Strength (min ksi) |
Rockwell Hardness (min) |
Rockwell Hardness (max) |
See Note |
---|---|---|---|---|---|---|---|---|
SAE J429 – Grade 2 | Low or Medium Carbon Steel | 1/4 thru 3/4 | 55 | 74 | B80 | B100 | – | |
over 3/4 thru 1-1/2 | 33 | 60 | B70 | B100 | – | |||
ASTM A307 – Grade A | Low or Medium Carbon Steel | 1/4 thru 4 | – | 60 | B69 | B100 | – | |
ASTM A307 – Grade B | Low or Medium Carbon Steel | 1/4 thru 4 | – | 60 min 100 max |
B69 | B95 | – | |
SAE J429 – Grade 5 | Medium Carbon Steel, Quenched and Tempered | 1/4 thru 1 | 85 | 120 | C25 | C34 | – | |
ASTM A449 – Type 1 | Medium Carbon Steel, Quenched and Tempered | over 1 thru 1-1/2 | 74 | 105 | C19 | C30 | – | |
over 1-1/2 thru 3 | 55 | 90 | 183 | 235 | NOTE | |||
ASTM A325 – Type 1 | Medium Carbon Steel, Quenched and Tempered | 1/2 thru 1 | 85 | 120 | C24 | C35 | NOTE | |
over 1 to 1-1/2 | 74 | 105 | C19 | C31 | NOTE | |||
ASTM A325 – Type 3 | Atmospheric Corrosion Resistant Steel, Quenched and Tempered | 1/2 thru 1 | 85 | 120 | C24 | C35 | NOTE | |
over 1 to 1-1/2 | 74 | 105 | C19 | C31 | NOTE | |||
ASTM A354 – Grade BC | Medium Carbon Alloy Steel, Quenched and Tempered | 1/4 thru 2-1/2 | 105 | 125 | C26 | C36 | – | |
over 2-1/2 thru 4 | 95 | 115 | C22 | C33 | – | |||
SAE J429 – Grade 8 | Medium Carbon Alloy Steel, Quenched and Tempered | 1/4 thru 1-1/2 | 120 | 150 | C33 | C39 | – | |
ASTM A354 – Grade BD | Medium Carbon Alloy Steel, Quenched and Tempered | 1/4 thru 2-1/2 | 120 | 150 | C33 | C39 | NOTE | |
over 2-1/2 thru 4 | 105 | 140 | C31 | C39 | NOTE | |||
ASTM A490 – Type 1 | Medium Carbon Alloy Steel, Quenched and Tempered | 1/2 thru 1-1/2 | 120 | 150 min 170 max |
C33 | C38 | – | |
ASTM A490 – Type 3 | Atmospheric Corrosion Resistant Steel, Quenched and Tempered | 1/2 thru 1-1/2 | 120 | 150 min 170 max |
C33 | C38 | NOTE |