Minimum wall thickness

[tobbie]

I have a piece of equipment that has M6 holes drilled into structural steel that I believe are too close to the edge of the steel block. What is the industry standard wall thickness for tapped holes in structural steel? I’ve heard 1 x hole size; 1.5 x hole size. (I’m referring to the edge of the block to the tangent point of the hole)

Thanks for assistance.

 

[digger200]

Think of a nut, I'm sure that won't be much

 

[dvd]

The 1 to 1.5 x hole diameter dimensions are related to punched holes, as the material can deform due to punch forces when the edge distance is less.

 

[tobbie]

Actually, the standard rule of thumb for stamping is 3x material thickness for hole to edge. This prevents the die from being too weak in the case of a compound die where you´re punching both the hole and the outer shape at the same time.
I´m not sure I'm sold on the nut comment from a previous reply. A nut has opposing forces so wouldn´t the wall thickness naturally be less than a hole machined into a block of steel?

 

[MachinaMan]

Check for tearout.
Look at the radial forces in the bolt/stud/etc.