SAE J429 Mechanical and physical property for the different property classes of bolts, screws and studs
SAE J429 covers the mechanical and material requirements for inch series fasteners used in automotive and related industries in sizes to 1-1/2” inclusive.
Below is a basic summary of the most common grades.
| GRADE | Nominal Size, inches | Full Size Proofload, psi | Yield Strength, min, psi | Tensile Strength, min, psi | Elong, min, % | RA, min, % | Core Hardness, Rockwell | Tempering Temperature, min |
|---|---|---|---|---|---|---|---|---|
| 1 | 1/4 thru 1-1/2 | 33,000 | 36,000 | 60,000 | 18 | 35 | B7 to B100 | N/A |
| 2 | 1/4 thru 3/4 | 55000 | 57000 | 74000 | 18 | 35 | B80-B100 | N/A |
| Over 3/4 thru 1-1/2 | 33,000 | 36,000 | 60,000 | 18 | 35 | B70 to B100 | ||
| 5 | 1/4 thru 1 | 85,000 | 92,000 | 120,000 | 14 | 35 | C25 to C34 | 800F |
| Over 1 thru 1-1/2 | 74,000 | 81,000 | 105,000 | 14 | 35 | C19 to C30 | ||
| 8 | 1/4 thru 1-1/2 | 120,000 | 130,000 | 150,000 | 12 | 35 | C33 to C39 | 800F |
| Grade 2 requirements for sizes 1/4" thru 3/4" apply only to bolts 6" and shorter, and to studs of all lengths. For bolts longer than 6", Grade 1 requirements shall apply. | ||||||||