Program Development Of Canned Cycle Instruction In Cnc Milling

Nowadays CNC technology is widely used in various manufacturing. When processing machinery parts with CNC machine, we often encounter such situations that the blank size of a work piece is much larger than the final size of it and several features processed are ordered in a rule. In these situations, many repetitively regular processes are necessary. Facing to some situations in CNC processing like the situation above, many CNC system adopt canned cycle instruction to deal with it. This method is expressing processing functions of many regularly fundamental instructions with cycle instruction that the CNC system of itself can identify.Canned cycle instruction of CNC system makes programming become more simplified and improves cutting efficiency. Canned cycle instruction exists in CNC system of medium and high grade in some countries around the world. In canned cycle instruction, SIEMENS CNC system of Germany and FANUC CNC system of Japan are typical and lead the way in the world. In the programming process, the use of canned cycle instruction can bring double effects. And the structure of the program is clear and logical. The readability is greatly improved compared with the general programming instruction.Program development of milling canned cycle instruction in open CNC system of CNC technology laboratory of HIT was researched. First of all, external characteristic of several milling canned cycle instructions was analyzed. The instructions included radial slot milling, circumferential slot milling, rectangle slot milling, round slot milling and plane milling of Siemens CNC system. Appropriate instruction format, tool path and coding program were designed, and coding module of CNC system of CNC technology laboratory of HIT was expanded. Secondly, rationality and accuracy of these canned cycle instruction were proved by two simulations. One of the methods was programming simulation authentication program of tool path of fundamental instructions converted from canned cycle instructions with Visual C++ software, the other was simulation processing of converted basic instructions with Swan CNC simulation software. Finally, programs written including of the five milling canned cycle instructions were processed practically in open CNC system. The effect of processing met the expected standard, so the milling canned cycle instructions were verified well in actual processing.