hand spanners lenght standards

[ww2]

The length of standard spanners is determined to develop a tension to the bolt of according to:

ASME B31-3 S= 45000/Vd, with s = bolt tension and Vd= square root of bolt diam.
EN 1591 FBoav = AB x 1000/ VdBO, with FBoav = bolt force VdBO square root of bolt diam.
AB = effective bolt section
Are there different lengths of hand spanners on the market for different bolt material classes, for Anglo-Saxon as well as European standards. Certainly European bolts have huge differences in material strengths: 3.6 to 12.9. (300N/mm² to 1200N/mm²)
If there are differences in lengths of the hand spanners for different bolt strengths, according to what standards are the made. Is there any corrolation?
Please help
Raymond

 

[evelrod]

My guess is that you are "over thinking" the problem. Adjustable torque wrenches would fit the bill but, hand wrenches are designed more for utility and appearance. More for operator 'fit' than for any mechanical consideration.
A 6" long wrench 'can' give identical torque readings as a 12" long wrench---just need more 'umph' on the end of it.

Rod

 

[ZoltanT]

The length of a spanner would be a compromise between the force needed on the end to provide sufficient torque and how it fits into its environment. Many motor mechanics prefer shorter handled spanners since they are less likely to interfere with other components in a crowded engine bay as they swing. A long-handled spanner may require the mechanic to remove other things to clear up some "swinging room" for the spanner.

If you need more torque than you can apply by hand (to crack free that stubborn, half-rusted nut), a soft hammer will usually do the trick. Good quality spanners will handle this treatment well.

 

[Pekelder]

Yesterday I saw a guy on a motorcycle with a spanner hanging across his back. It was over 3 ft (1 meter) long and seemed not to be bigger than 30-32 mm. Seems he wanted to give a big 'umph' to a bolt somewhere ;-)

Regards,

Pekelder