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Tonnage Charts / Bending Help

notes regarding tonnage charts


The charts show the force/pressure (F) required for air-bending.   The force/pressure (F) required for bottoming/coining is between 3 and 8 times higher than for air bending.

The die opening (V) would typically be 6 times the material thickness up to t=1.5mm and as high as 10 times the material thickness for t=10mm.


When deciding what v-size (V) to use, consideration needs to be given to the shortest flange required (b) and internal radius (r) required.    Note that the natural internal radius comes from the v-size selected rather than from the punch-tip radius.


The figures shown in the charts here are for guidance purposes only.

Mild Steel Tonnage Chart

air bending image.png
coining image.png

Stainless Steel Tonnage Chart

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