Wire cutting is mainly used to process complex and precise workpieces. It has many outstanding advantages, such as small processing allowance, high processing accuracy, short production cycle and low manufacturing cost. It has been widely used in production. The processing technology of WEDM is as follows.
High speed and stable cutting: high peak current and long pulse width are selected for high current cutting to achieve high cutting speed. The compensation of the center trajectory of the electrode wire is small. The larger the selection, the faster the second cutting. The smaller the selection, the more difficult it is to eliminate the traces of the first cutting. High-speed wire-drawing is adopted, and the speed of wire-drawing is 8-12 m/s, which achieves the maximum processing efficiency.
Refinement to ensure dimensional accuracy: The pulse parameters are moderately regulated so that the roughness Ra after the second cutting is between 1.4 and 1.7 microns. Compensation f, because the second cutting is refinishing, the discharge gap is smaller at this time, delta is less than 0.01 mm, while the third cutting requires little processing quality, only a few microns, the sum of the two is about 0.01 mm. Therefore, the second cutting compensation f is about 1/2d + 0.01mm. In order to achieve the purpose of finishing, low-speed wire traveling is usually adopted, the speed of wire traveling is 1-3 m/s, and the tracking feed speed is limited within a certain range, in order to eliminate the circular cutting fringes and obtain the required dimensional accuracy.
Polishing and polishing: The minimum pulse width is used for polishing, and the peak current varies with the surface quality requirements. In theory, the radius of the wire and the discharge gap of 0.003 mm are added. In fact, the finishing process is a kind of EDG, and the amount of processing is very small, which will not change the size of the workpiece. Therefore, only the radius of the electrode can be used as compensation to achieve the desired effect. The wire traveling mode is as low as the second cutting, and the speed-limited feed can be used.
Punch processing technology: Punch plays an important role in the die. Its design shape, dimension accuracy and material hardness directly affect the quality of punching, service life and precision of stamping parts. Cutting line should be helpful to ensure that the workpiece is always in the same coordinate system with the fixture (clamping support) in the process of processing, avoiding the influence of stress and deformation.
