In Reply to: Re: Torque Guides posted by Jock (OR) on March 17, 2021 at 21:10:59:
The engineering formulas for torque to tension calculations contain a friction coefficient term called the "K-factor". The lower the K-factor the more tension produced for the same applied torque. In practice there is a wide variation in the predicted versus actual tensions produced for any given fastener and thread condition. In general the lower the K-factor the more reliable the torque to tension calculations become. Here is a table showing how various thread conditions affect K-factor and the "scatter envelope" of the resulting values. As you can see Loctitie generally reduces the K-factor resulting in more reliable tension results. Data and claims courtesy of Henkel.
PS> Any fastener torque chart that does not specify thread conditions used in the calculations is not worth the time it takes to read it.