Drawing Die Design of Multi-head Wire Drawing Machine

Die structure design

1.Entrance area design:

① The entrance area mainly plays the role of guiding the metal wire smoothly into the mold. Its shape is usually trumpet shaped, and the Angle is generally between 60° -90 °. For example, when drawing copper wire, the entrance Angle can be set to about 70°, which can reduce the resistance of the wire into the mold.

② The length of the entrance area is usually determined according to the diameter of the wire and the overall size of the mold, and the general length is 1-2 times the diameter of the wire. The surface roughness requirement of the entrance area is low, usually Ra reaches 0.8-1.6μm to prevent scratching the wire.

2. Lubrication area design:

① The lubrication area is to form a lubricating film on the surface of the wire to reduce the friction during the drawing process. The length of the lubrication zone is generally 3-5 times the diameter of the mold.

② The structure of the lubrication zone can be in the form of annular groove or spiral groove. The width and depth of the annular groove are generally between 0.2-0.5mm, and the pitch of the spiral groove can be designed according to the drawing speed and lubrication requirements, generally between 1-3mm.

3. Compression area design:

① The compression area is the core part of the mold, which determines the deformation degree and dimensional accuracy of the wire. The length of the working area is determined according to the drawing ratio and the wire material, the larger the drawing ratio, the longer the working area length.

②The shape of the compression area is generally conical, and the cone Angle is usually between 3° -12 °. For metal wires with higher hardness, the cone Angle can be appropriately reduced to avoid wire breakage. The diameter accuracy of the working area is very high, and the tolerance is generally controlled within ±0.005mm.

4.Sizing area design:

① The sizing area is mainly to accurately control the final size of the wire. The length of the sizing zone is generally 0.5-1 times the diameter of the wire.

②The diameter tolerance control of the sizing area is extremely strict, generally within ±0.002mm, to ensure that the size of the wire is uniform after drawing.

5.Design of decompression /exit area:

The function of the decompression outlet area is to make the drawn wire leave the mold smoothly. The shape of the exit area is trumpet shaped, the Angle is generally between 30° -60 °, and the length is 0.5-1 times the diameter of the wire.