Screw threads appear to be a simple concept yet much confusion and inconsistency exist regarding torque values. The mechanics of the screw thread are actually very complex and have numerous interacting variables. Sliding friction is affected by materials (like steel or aluminum on titanium), surface roughness, bearing area, material hardness, lubrication and so on.

Accuracy: Tightening is not an accurate science, look at the preloading accuracy published in the "Machinery's Handbook, 25th Edition, page 1404"

Recommended Torque Spec's for Titanium Fasteners

Use torque values specified by your equipment manufacture, when available. For titanium fasteners the torque values are listed below. We recommend anti-seize or moly paste be applied to the threads.

The importance of correct application cannot be overemphasized. Undertorque can result in unnecessary wear of nuts and bolts as well as the parts they hold together. When insufficient pressures are applied, uneven loads will be transmitted throughout the assembly which may result in excessive wear or premature failure due to fatigue. Overtorque can be equally damaging because of failure of the bolt or nut from overstressing the thread areas.

(For bolts in shear reduce the values shown below by 30-40%)