Punching capacities calculator (diameter)


POT. = (p x e x sT)/1000
TONNAGE = perimeter x thickness x strength
Kgs. = mm. x mm. kg/mm2
Kgs. / 1000 = Tns.

Please refer to the below drawing for more information about how to calculate the perimeter (p) of the most common shapes.


Never punch a diameter smaller than the material thickness

Select a shape and enter measurements:

Fill in two of the three first fields and get the result for the missing field.
Resistance is a compulsory field.
Example: for a given diameter, thickness and strength*, work out the tonnage.

Usual material strengths:

Low carbon steel 38 kg./mm2
Mild steel 45 kg./mm2
Stainless steel 85 kg./mm2
Copper 22 kg./mm2

Nevertheless, it is very important to apply
the correct gap between punch and die:

Aluminum 5 %
Copper 7 %
Mild steel (ST37 to 42) 10 %
Mild steel ST52 12 %
Stainless steel 15 %
% material thickness = gap