General mechanics
Shaft and Lever-Arm Torque Calculator
Calculate steady torque from power and rotational speed, or from a tangential force and radius. An optional multiplier is applied only when you provide its traceable source.
Torque arithmetic
The familiar coefficient is 60000/(2π)=9549.296596…; using the exact expression avoids rounding the coefficient to 9549. These are general mechanics equations, not coupling-standard sizing formulas.
Svetainė NIST Guide to SI identifies watt, rad/s and N·m as the relevant derived units. Its conversion appendix gives 1 lbf·ft=1.355818 N·m and standard gravity fixes kgf conversions.
ISO 10441:2007 applies to specified special-purpose flexible couplings in petroleum/petrochemical/gas service and explicitly does not define criteria for selecting coupling types. Its scope cannot justify a universal service-factor lookup for every coupling.
