How to make a metal wire drawing die?

Drawing (also known as deep drawing, deep drawing) is a common process in stamping process, because it is suitable for all walks of life and has wide practicability. From blank to stretch forming, it needs to be completed in multiple steps: primary stretching → secondary stretching → … → forming.

First, the concept of stretching:

1. stretching: pressing the sheet into a hollow part (the wall thickness is basically unchanged).

2. Stretching process: the material on the plane (flange) is transferred to the cylindrical (box-shaped) side wall, so the size of the plane changes greatly.

3. Tensile coefficient: the ratio of tensile diameter to blank diameter "m" (deformation degree from blank to workpiece).

Second, the drawing process arrangement:

1. Parts with thin material and drawing depth greater than diameter: The fillet radius can be gradually reduced by reducing the cylinder diameter to increase the height.

2. Parts with thick materials and similar drawing depth and diameter: Under the condition of keeping the height unchanged, the fillet radius can be reduced in the process of gradually reducing the cylinder diameter.

3. The flange is very big and the circle radius is very small: it needs to be reshaped many times.

4. When the flange is too large, strain bulging method shall be adopted if necessary.

In order to embody the principle of "unchanged flange" and prevent the flange formed in the first drawing from participating in the subsequent drawing deformation, the material of the wide flange after drawing thinning (that is, the material forming the wall and bottom) should be 3~ 10% more than the material actually needed in the final drawing.

Note: When calculating the stretching multiple by area, the upper limit is taken, otherwise the lower limit is taken. These extra materials will return to the flange in the later drawing step, which will cause the flange to thicken but avoid the head cracking. The local thinning area can be corrected by shaping. Therefore, it is very important to strictly control the stretching height of each stretching.

Mold design process:

After the customer provides the drawing samples,

Drawing evaluation

1。 Confirm processing technology

2。 cite

3。 Draw mold drawings (drawing software such as AUTO CAD/UG/SOLIDWORKS).

4。 plot

5。 Buy mold materials, mold parts

6。 Material preparation for mold processing

7。 heat treatment

8。 Grinding and wire cutting by grinding machine

9。 Put it together.