Elongation set
Standard tolerances (see: Natural diamonds, Techn. spec.) are based on the postulation that in relation to the theoretical wire elongation
1 % of deviation in Diameter or
2 % of deviation in Elongation
can be “tolerated”. Either by slippage of the wire on the drawing cones resp. rings or by the “good nature” of the material to be drawn.
But in contrary conditions this could lead to 5 % deviation in elongation. In the diameter range below 0,1 mm and with multi-wire drawing machines this is too unprecise. Fouling or breakage of the wire can occur.
To prevent this we at REDIES apply 3 different manufacturing methods for making die sets:
1. Wire elongation (conventional method)
Sets are manufactured (or repolished) with the maximum deviation in elongation of +/- 1 %.
Beginning with the biggest diameter die after die is polished “into the tolerance”. Wire elongation is repeatedly controlled by wire elongation measuring machine.
Checking the wire-elongation
This method is very precise but time consumptive and requires a surcharge.
2. Method of half the standard tolerance
Application of micro-scales (cutting a certain length of Wo- or Cu-wire) or laser micrometer measuring permits a 50 % reduction of the standard tolerance.
Dies can be produced in batches. This method is less time consumptive than the conventional wire elongation method but almost as reliable.
3. REDIES Matrix Method
Especially for the manufacturing and repolishing of sets for multi-wire drawing machines.
Initially the dies are manufactured (repolished) by the method of the reduced tolerance into the lower tolerance range.
After this the dies are sorted in a matrix
Final dies horizontally beginning with the smallest actual dimension to the left….
biggest to the right.
then
Next nominal size beginning with the smallest…
Afterwards dies are compilated according to sets in the vertical
Thus more sets in one machine means less deviation from the theoretical wire elongation within the single set.
Small adjustments after measuring the wire elongation can be made easily.
Sets are provided with a measuring protocol.
Stand 01.2010