Development and application of EDM Drilling

The electric EDM Drilling is used as a method to process the thread of nc machine tool. Firstly, it is popular in Europe. With the development of China's numerical control machine, it is gradually accepted and enjoyed by the customers in China. The electric EDM Drilling is used to complete the electric EDM Drilling by using the three-axis linkage function of CNC machining center and G02 or G03 screw interpolation instructions.

The machining method of edm has certain natural advantages. Due to the current edm for carbide drill manufacturing materials, processing the linear speed of 80-200 - m/min, when high speed steel tap processing speed for 10 to 30 m/min, so the edm drill is suitable for high speed cutting, improve the processing thread surface finish; For high hardness materials, high temperature alloy materials, such as titanium alloy, nickel base alloy thread processing has always been a difficult problem, mainly because of the high speed steel tap thread machining, the tool life is shorter, and the carbide edm drilling in hard materials thread processing effect is the ideal solution. Machining hrc58-62. To the high temperature alloy material of thread machining, edm drilling also showed a very excellent processing performance and long life than expected, on the same pitch, threaded holes of different diameter, USES the tap, need more to complete the cutting tool processing, but if use edm drilling, using a tool; In the tap wear, after processing thread sizes smaller than tolerance, cannot continue to use, can only be scrapped, and because the edm drill wear and machining threaded hole size is smaller than tolerance, through numerical control system, the necessary tool radius compensation adjustment, can continue to work out qualified size of thread. Similarly, in order to obtain high precision thread holes, it is much easier to adjust the radius of the tool than to produce high-precision tap. For small diameter of screw thread processing, especially in the material of high hardness and high temperature material thread processing, tap broken, sometimes blocking threaded hole, even make the parts scrap, using edm drilling, due to the cutting tool processing of hole diameter ratio is small, even if broken, will not be blocked thread hole, very easy to remove and will not lead to parts of scrapped; Using edm drill, cutter cutting force reductions and compared with those of tap this to large diameter thread processing, is particularly important to solve the machine load is too big, can't drive tap normal processing problem.

Machine clip blade type edm drilling has been ten years ago, people also realize the M20 threaded hole, on the machining center processing, compared using edm drill and tap, would greatly reduce the processing cost. But in recent years, the overall hard alloy electric EDM Drilling design and production technology have gradually matured, and developed a range of products in a range of sizes.

For small diameter of screw thread processing applications, such as an aviation enterprise, needs to be on a aluminum processing 50 m1.6-m7 x 0.35 thread, blind holes, the customer's problems is that being blind holes, chip removal is difficult, the tap processing is adopted to tap is easy to break; Because the tapping is the last process, such as part scrapping, the loss of the amount of processing time spent on the part. Finally, the customer chooses processing m1.6-m7 x0.35 thread edm drill, Vc (linear velocity) = 25 m/min, S (RPM) = 4900 r/min (limit) machine tool, fz turn (feed)/r = 0.05 mm, the actual processing time for 4 seconds/thread, a cutting tool has completed all 50 pieces of artifacts.