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screw used as an axle
shear critical joint in aircraft strut
Torque values derived from charts assume tension joints
may or may not be correct when used in shear.
Fully threaded screw used as an axle on aircraft throttle lever. Hardened steel threads in screw will soon cut into the soft aluminum levers causing throttle binding.
Bolt used as a shear pin. Bolt threads should not extend into the shear plane.

A bolt is a tension device that clamp joints together. Its purpose is to produce tension by fully tightening the bolt. Bolt tension keeps the nut from loosening.

However, a bolt used as a shear pin in a bearing-type shear joint is not in tension. Bolt tightening is to secure the bolt to the joint and not produce tension. A "bearing-type" shear joint is one in which the bolt or pin takes the load as in the picture above. Example is a rivet.  Far less torque is needed or desired in a bearing-type joint. Some secondary anti-rotation device is needed to retain the nut.

Bolt torque specifications derived from standardized torque charts assume tension joints and this can get you into trouble if you apply the torque chart incorrectly to your job.

There is another type of shear joint called, a "slip-critical" joint.  Friction between the faying surfaces prevents the joint from slipping. The bolt is fully tightened to produce a large clamping force (friction).

The same bolt can have widely different toques depending on the design and needs of the joint. The arbitrary use of "standard" torque charts can be misleading if you do not have an understanding of what you are trying to achieve with torque.
Mechanic's Toolbox - Software for the Mechanic
40 software programs written especially for the mechanic
Mechanic's Toolbox includes: Anti-Seize Selector, Torque Wrench Calculator, and Bolt Strength Calculator. Compute torque from bolt strength, clamping force, breaking strength, shear strength. Includes strength charts,torque wrench extension calculations, torque conversion charts, standard torques for most nuts, bolts and screws, K factors, torque accuracy. etc.