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% |