I am working on torquing an M5 bolt but the torques listed on this website are so low, I highly doubt I will get to 85% of the proof load of a bolt.
https://www.engineeringtoolbox.com/metric-bolts-maximum-torque-d_2054.html
I feel that the torque needs to be much higher to reach that stretch in the bolt for the different grades.
How do they say that they achieve that much stretch considering only 10% of the torque effort actually stretches the bolt? 85% elastic stretch is like tensioning the bolt in pure tension on a universal tensile testing machine where friction doesn’t exist in the test.
Please explain / advise.
Comments
You could always try finding the failure torque. I would be surprised if an M5 bolt lasted much past 15 Nm. Consider how much smaller the bolt radius is compared to whatever tool you’re using to tighten it with…there’s a very large force multiplication factor involved.
Try what it can take.
10 Nm sounds more than enough for M5.
What grade bolt do you have? What is the lubrication condition?
I’m not sure what makes you think this is wrong. Threads are very effective at converting torque into axial force. I’m not sure where you got that 10% number from. Besides, 10% of what? Torque and clamp load don’t even have the same units.