Overview
In order for a fastener to perform its job, it must be appropriately pre-loaded. All fasteners shall have an installation torque called out on their assembly document. To determine the appropriate torque for a fastener, a specific value may be determined or a value my be used from the reference tables below.
Grade 8 Steel Fasteners
All calculations are for lubricated, non-galvanized fasteners.
| Size | Major Diameter [in] | Minimum | Nominal | Do Not Exceed | Notes |
|---|---|---|---|---|---|
| #2-56 | .086 | 2.1 | 2.5 in-lbs | 4 in-lbs | |
| #4-40 | .112 | 4.4 | 5.2 in-lbs | 8.7 in-lbs | |
| #6-32 | .138 | 8.2 | 9.6 in-lbs | 16.3 in-lbs | |
| #8-32 | .164 | 16.8 | 19.8 in-lbs | 33.7 in-lbs | |
| #10-24 | .190 | 19.4 | 22.8 in-lbs | 41 in-lbs | |
| 1/4-20 | .25 | 63.9 | 75.2 in-lbs | 143 in-lbs | |
| 5/16-18 | .313 | 112 | 132 in-lbs | 295 in-lbs | |
| 3/8-16 | .375 | 201 | 236 in-lbs | 528 in-lbs |