Torque values for various grades and diameters of fasteners.

Each bolt grade has an ideal tightening torque for maximum clamping force without breaking. Grade 2 bolts are cheap but not very strong, grade 8 bolts are the strongest and most expensive, and grade 5 …

Grade 8 Bolt Drill & Torque Chart in Foot Pounds ... This technical information is supplied as a courtesy.

Torque-Tension Relationship for A307A, Grade 5, 8 & 9 Bolts ... The torque values can only be achieved if nut (or tapped hole) has a proof load greater than or equal to the bolt's minimum ultimate tensile …

Nov 20, 2025 · Bolt torque specifications chart for Grade 2, 5, and 8 bolts. Includes proper tightening specs, torque values, and installation tips to prevent bolt failure.

Cross-reference the bolt size and grade to find the recommended torque value. The chart provides torque specifications in inch-pounds (in.-lbs.) or foot-pounds (ft-lb).

If you need to torque a critical fastener and you can't find a manufacturer's torque spec, you can use the charts below for the maximum recommended torque values for different grades and sizes of fasteners.

Bolt torque chart reference guides include Grade 2, B7, A307, A325, Grade 8, A490, and Grade 5. AFT Fasteners is your trusted source for fastener information.

Thread Length Formula: For bolts 6” and shorter – twice the diameter plus 1⁄4” – (2D + 1⁄4”) Longer than 6” – twice the diameter plus 1⁄2” – (2D + 1⁄2”) When bolts are short for formula thread length, thread …

Grade 8 Metric Bolt Torque Chart The prevailing torque lock nut clamp loads are listed at 75% of the proof loads specified for the appropriate grade bolt: This table shows values for threads that have …