Punches and Dies

European producers for punching tools.

The table shows the roughness as a function of the conditions of the mold.
The roughness of the surfaces may of course be reduced sheared immediately after punching through a
operation reworking.
And 'interesting to consider hours percentile surface gloss punched in the total area
generated by cutting, and the ratio between surface and after punching looks shiny and smooth and
rough surface corresponding to the area of tear.
As mentioned the punching end allows the generation of sheared surfaces almost perfect and
then totally smooth without stripping zone when certain conditions are met.
The cost of production is improved when it is possible, however, accept the presence of more or less
limited areas of tearing that is when the demands placed on surfaces to allow punching a quantity
surface smooth and polished below 100%.
E 'therefore appropriate to define the extent of the area of real punching than to tear
it is advisable to indicate on the design of the piece the value of the relationship between the two areas above,
statement that will be invaluable for the manufacturer of the matrix and the punch and who will provide the piece
punch.

DIES TOLERANCE IN PERCENTAGE TO THICKNESS

Material Thickness Range Minimum or Blanking* Standard Maximum
Aluminum
Copper
Brass
20÷25% Kg/mm2
Up to mm 2 8% 10% 12%
From mm 2
to mm 4
10% 12% 15%
Over mm 4 12% 15% 20%
Mild
steel
30÷40% Kg/mm2
Up to mm 2,5 15% 18% 20%
From mm 2,5
to mm 5
18% 22% 25%
Over mm 5 20% 25% 30%
Stainless
steel
60÷80% Kg/mm2
Up to mm 1,5 15% 20% 22%
From mm 1,5
to mm 3
18% 22% 25%
Over mm 3 20% 25% 28%

Punches and Dies
To smooth the area means the portion of the seal, which is generated through real cutting
(not stripping) of the material and is smooth.
The location of rupture is defined as the portion of the surface always considered in the sense in which the thickness
separation occurred sliced element excision but not for tearing, a phenomenon that
edge of the material verification sheet corresponding to the output of the punch.

Dies for punching.

Matrices and their punches to punch for this type of work can be divided into
two basic types, namely
A) dies to punch hard
B) molds punch Mobile
The first type can be used for any event, the workpiece and the condition of employment, while those of the second
type (punch mobile) are used only for relatively thin material thickness and characterized
a few holes.