Precautions For The Processing Of Lower Speed Wire Cutting Die

1. Machining Technology of Small Corner of Die Block Hole

As the diameter of the selected EDM brass wire is larger, the corner radius of the cut hole is also larger. When the corner radius of the inner hole of the block is required to be small (for example: R0.07—R0.10mm), the thin electrode wire must be replaced (such as the EDM brass wire of Φ0.10mm). However, compared with EDM brass wires of Φ0.20mm and Φ0.25mm, the processing speed of thin wires  is slow and expensive. Therefore, if all the inner hole is processed with thin wires, it will prolong the processing time and cause waste. After careful comparison and analysis, it is most appropriate to take the following method: first increase the corner radius appropriately, cut all inner holes with EDM brass wires of Φ0.20mm and Φ0.25mm, and then use the thin wires to uniformly trim the corners of all inner holes to meet the specified size requirements.

Example: wire cutting processing technology of rectangular tooth-shaped die block (inner corner radius is R0.07mm)

a. First, use Φ0.20mm EDM brass wire to process the inner hole of the block to the required size, and process the inner corner to R0.15mm;

b. Replaced with Φ0.10mm EDM brass wire;

c. After replacing the thin wires, it is necessary to replace the nozzle, power feed contact, tension roller, guide wheel, belt and other consumables. Because after being used by the thick wires, some wider and deeper grooves have been formed on the surface of power feed contact, tension roller, guide wheel and belt, and the thin wires are prone to be stuck or slipped;

d. Modify the corner radius of the graphics, reprogram, avoid other inner hole contour lines, and trim the corner radius of the inner hole to R0.07mm.

2. The processing sequence of multi-hole die block, fixed plate and stripper plate

For multi-hole die block, fixed plate and stripper plate, considering the slight deformation of each inner hole due to the influence of residual stress and processing heat during processing, the method of consistent inner hole processing sequence is adopted in actual production to ensure the consistency of the inner hole position deformation, and then ensures the concentricity of the holes of the die block, fixing plate and stripper plate.

Fully understand the structural performance of the machine tool and master the operation skills of the machine tool, reasonably select the jet and discharge parameters, reduce the broken wire in the processing, and constantly summarize the experience and lessons in practice, so as to maximize the potential of machine tool, increase productivity.