Quote:
Originally Posted by JFP in PA
Sorry, but that is not remotely correct. To assure you obtain the correct torque settings, and the targeted clamping force, the fasteners (including washers) should be lubricated. This is particularly important in torque to yield applications like the flywheel bolts. Optimal repeatable results can be obtained using something like ARP's Ultra Torque compound, but in cases of dissimilar metals where later corrosion and thread galling is likely to occur, an anti seize compound should be used. When using a lubricant, no change in the torque wrench settings should be used, just apply the recommended torque.
If you want to see more information on the subject, check out ARP's website, they have an extensive white paper on what actually happens to the resulting torque (and clamping force) repeatability with and without lubrication, with vastly more data then you will probably ever need.
|
We're talking about two different applications, I agree that critical fasteners are always specified with OIL, or specially formulated lubrication like ultra-torque. We were discussing "generic" body fasteners, which all torque charts list as "clean and dry" threads. As compared to that specification, oil will slightly lessen the required torque, but anti-sieze has a fairly large effect. Notice on the attached chart the the torque with A/S is reduced by 1/3. Once you start talking about old or damaged/corroded fasteners, it's hard to arrive at accurate torque values, there's just too many variables.
http://www.alliedsystems.com/pdf/Wagner/Forms/80/80-1057.pdf
Threaded Mode
