You can find most everything on the internet. The chart above should have been left where it was found though.
I'm a retired tractor engineer and one of my first training assignments was running the bolt lab for our construction machine division. A sign was in the lab: "torque is what we do; tension is what we want." We also want consistency. On the assembly line, every bolted joint is set to a specification. That spec is determined in the lab; MANY bolted joints were torqued to "proof".... meaning: it is the torque (and tension) of a bolt at its yield point. The torque set on the line is then backed off by the plus tolerance of the wrenching system. Consistancy is everything. If a new shipment of bolts differ (supplier, plating, etc) bolts start breaking on the line.
Every kind of bolt finish imaginable is tested: raw, phos & oil, electro plate, mechanical plate, etc. Oiled bolts can be the most inconsistent of the bunch! Most consistent by far: dry mechanical plated.
Do NOT oil any bolt (on purpose) that a manufacturer has published a spec for. Fine threads don't offer any tension advantage either (any advantage is eaten up in additional thread friction)... because of that, they excel in high vibrational applications. Hope this helps.
