Strength Requirements by Grades
Yield strength , or working load limit, is the amount of stress a material can withstand without permanent deformation.
Tensile strength is the maximum amount of axial stress that a material can take before breaking.
All strength measurements are in ksi (kilo-pound per square inch). To find the actual weight a bolt can withstand you would have to multiply by the area of the cross section of the bolt.
1 ksi = 1000psi
SAE Bolts / Sockets
SAE J429
| Grade |
Material |
Size Range |
Yield (ksi) |
Tensile (ksi) |
Hardness |
| Grade 2 |
Carbon Steel |
1/4 - 3/4 (7/8 - 1 1/2) |
57 (36) |
74 (60) |
B80-B100 |
| Grade 5 |
Carbon Steel |
1/4 - 1 (1 1/8 - 1 1/2) |
92 (81) |
120 (105) |
C25-C34 |
| Grade 8 |
Alloy Steel |
1/4 - 1 1/2 |
130 |
150 |
C33-C39 |
| Sockets |
Alloy Steel |
< 1/2 (1/2 - 2) |
162(153) |
180 (170) |
C38-C45 |
Common Stainless Grades
More Grades
| Grade |
Material |
Size Range |
Yield (ksi) |
Tensile (ksi) |
Hardness |
| 304 |
S/S 304 |
1/4 - 1 1/2 |
40 |
85-150 |
B85-B95 |
| 316 |
S/S 316 |
1/4 - 1 1/2 |
40 |
85-140 |
B85-B95 |
ASTM
| Grade |
Material |
Size Range |
Yield (ksi) |
Tensile (ksi) |
Hardness |
| A307 GR A |
Carbon Steel |
1/4 - 4 |
- |
60 |
B69-B100 |
| A307 GR B |
Carbon Steel |
1/4 - 4 |
- |
60-100 |
B69-B95 |
| F1554 GR 36 |
Carbon Steel |
1/4 - 4 |
36 |
58-80 |
- |
| F1554 GR 55 |
Carbon Steel |
1/4 - 4 |
55 |
75-95 |
- |
| F1554 GR 105 |
Carbon Steel |
1/4 - 3 |
105 |
125-150 |
- |
| A193/A320 B8 |
S/S 304 |
- |
30 |
75 |
B96 |
| A193/A320 B8M |
S/S 316 |
- |
30 |
75 |
B96 |
| A193 B7 |
Alloy Steel |
1/4 - 2 1/2 (2 5/8 - 4) |
105(95) |
125 (115) |
C35 |
| A325 |
Carbon Steel |
1/2-1 (1 1/8 - 1 1/2) |
92 (81) |
120 (105) |
C24-C35 |
| A449 |
Carbon Steel |
1/4 - 1 (1 1/8 - 1 1/2) |
92 (81) |
120 (105) |
C25-C34 |
| A490 |
Alloy Steel |
1/2 - 1 1/2 |
130 |
150-173 |
C33-C38 |
Metric
| Grade |
Material |
Yield (ksi) |
Tensile (ksi) |
Hardness |
| 4.6 |
Low Carbon Steel |
35 |
58 |
B67-B95 |
| 5.8 |
Low Carbon Steel |
60 |
75 |
B82-B95 |
| 8.8 |
Medium Carbon Steel |
92 |
120 |
C22-C34 |
| 10.9 |
Alloy Steel |
136 |
150 |
C32-C39 |
| 12.9 |
Alloy Steel |
159 |
176 |
C39-C44 |
