Medium Wire Cutting Machine Tool Processing Technology

The first cutting task is high-speed and stable cutting
⑴ Pulse parameters: Use high peak current and long pulse width for high current cutting to obtain higher cutting speed.
⑵ The compensation amount of the center track of the electrode wire is small:
f = 1/2φd +δ+ △ + S, where f is the compensation amount (mm); δ is the discharge gap during the first cutting (mm); φd is the diameter of the electrode wire (mm); △ is the machining allowance for the second cutting (mm); S is the finishing allowance (mm). When the high peak current is used for rough standard cutting, the single-sided discharge gap is about 0.02mm; the finishing allowance is very small, generally only 0.003mm. The machining allowance △ depends on the surface roughness and machine tool accuracy after the first cutting, which is approximately in the range of 0.03-0.04mm. In this way, the compensation amount for the first cutting should be between 0.05-0.06mm. If it is too large, it will affect the speed of the second cutting, and if it is too small, it will be difficult to eliminate the traces of the first cutting.
⑶ Wire feeding method: high-speed wire feeding is adopted, and the wire feeding speed is 8-12mm/s to achieve the maximum processing efficiency.
The task of the second cutting is fine finishing to ensure the processing size accuracy
⑴ Pulse parameters: select medium standard, so that the roughness Ra after the second cutting is between 1.4 and 1.7μm.
⑵ Compensation amount f: since the second cutting is fine finishing, the discharge gap is small at this time, δ is less than 0.01mm, and the processing quality required for the third cutting is very small, only a few microns, and the sum of the two is about 0.01mm. Therefore, the compensation amount f of the second cutting is about 1/2d+0.01mm.
⑶ Wire feeding method: in order to achieve the purpose of fine finishing, low-speed wire feeding is usually adopted, the wire feeding speed is 1-3mm/s, and the tracking feed speed is limited to a certain range to eliminate the reciprocating cutting stripes and obtain the required processing size accuracy.
The task of the third cutting is polishing and finishing.
⑴ Pulse parameters: use the minimum pulse width for finishing, and the peak current varies with the surface quality requirements of the processing.
⑵ Compensation amount f: In theory, it is the radius of the electrode wire plus the discharge gap of 0.003mm. In fact, the finishing process is a kind of electric spark grinding, and the processing amount is very small, which will not change the size of the workpiece. Therefore, only using the radius of the electrode as the compensation amount can also achieve the ideal effect.
⑶ Wire feeding method: Just use low-speed wire feeding and limited speed feeding like the second cutting.