We offer high quality ASTM A320 L7 Bolts from 3/8" to 2" Diameter in multiple lengths and either standard thread length or custom thread length
A320 Grades
L7 Alloy steelL43 Alloy steelB8 Class 1 Stainless steelB8M Class 1 Stainless steelB8 Class 2 Stainless steelB8M Class 2 Stainless steel
AISI 4140/4142 Quenched and tempered |
AISI 4340 Quenched and tempered |
AISI 304, carbide solution treated |
AISI 316, carbide solution treated |
AISI 304, carbide solution treated, strain hardened |
AISI 316, carbide solution treated, strain hardened |
A320 Mechanical Properties
GradeDiameterTensile, ksi, minYield, ksi, minCharpy Impact 20-ft-lbf @ tempElong, %, minRA, %, min
L7 |
Up to 21?2 |
125 |
105 |
-150° F |
16 |
50 |
L43 |
Up to 4 |
125 |
105 |
-150° F |
16 |
50 |
B8 Class 1 |
All |
75 |
30 |
N/A |
30 |
50 |
B8M Class 1 |
All |
75 |
30 |
N/A |
30 |
50 |
B8 Class 2 |
Up to 3?4 |
125 |
100 |
N/A |
12 |
35 |
7?8 - 1 |
115 |
80 |
N/A |
15 |
35 |
11?8 - 11?4 |
105 |
65 |
N/A |
20 |
35 |
13?8 - 11?2 |
100 |
50 |
N/A |
28 |
45 |
B8M Class 2 |
Up to 3?4 |
110 |
95 |
N/A |
15 |
45 |
7?8 - 1 |
100 |
80 |
N/A |
20 |
45 |
11?8 - 11?4 |
95 |
65 |
N/A |
25 |
45 |
13?8 - 11?2 |
90 |
50 |
N/A |
30 |
45 |
A320 Chemical Properties
ElementL7 (AISI 4140)L43 (AISI 4340)B8 (AISI 304)B8M (AISI 316)
Carbon |
0.37 - 0.49% |
0.38 - 0.43% |
0.08% max |
0.08% max |
Manganese |
0.65 - 1.10% |
0.75 - 1.00% |
2.00% max |
2.00% max |
Phosphorus, max |
0.035% |
0.035% |
0.045% |
0.045% |
Sulfur, max |
0.040% |
0.040% |
0.030% |
0.030% |
Silicon |
0.15 - 0.35% |
0.15 - 0.35% |
1.00% max |
1.00% max |
Chromium |
0.75 - 1.20% |
0.70 - 0.90% |
18.0 - 20.0% |
16.0 - 18.0% |
Nickel |
|
1.65 - 2.00% |
8.0 - 11.0% |
10.0 - 14.0% |
Molybdenum |
0.15 - 0.25% |
0.20 - 0.30% |
|
2.00 - 3.00% |