Precision CNC machining has good flexibility and high level of automation technology. It is very suitable for processing curves with complicated contours, inclined plane parts, and complicated shells with many holes and grooves. Under this circumstance, the application of CNC lathe processing can obtain higher economic benefits. The solution of large and medium-sized cnc processing technology problems is basically the same as that of general processing, but it has its own characteristics. Therefore, when designing the CNC machining process of the planned parts, it is necessary to follow the CNC machining flexibility and the high level of automation technology, which is very suitable for processing curves with complex contours, sloped parts, and complex machining with many holes and grooves. Shells and prismatic parts can be processed by CNC lathes to obtain higher economic benefits under the conditions of various types, small and large batches of production.
The tool setting point and the tool change point of the large and medium-sized precision CNC machining center are clear. The tool setting point is the starting point of the fitness movement of the CNC blade relative to the workpiece during CNC machining. Because the program flow is also implemented from this point, the tool setting point is also called the program flow start point or tool start point. When writing the program, the selection of the tool setting point should be considered first. When the machining accuracy is not high, you can immediately use some surfaces on the workpiece or fixtures to face the dry cutting edge; when the machining accuracy is high, the tool setting point should be set as far as possible on the design scheme standard or processing technology standard of the part. For parts with precise hole positioning, it is more suitable to take the pivot of the hole as the tool setting point. The tool setting point must have a certain coordinate relationship with the precise positioning standard of the workpiece, so that the relationship between the CNC lathe coordinate system and the workpiece plane coordinate can be clearly defined. The selection of the tool setting point should be conducive to the calculation of the plane coordinates and make the tool setting convenient. During tool setting, the tool setting point should be overlapped with the tool position point. To put it bluntly, for the thick-bottomed alloy milling cutter, it is the intersection point between the center line of the index-controlled blade and the bottom edge of the CNC blade; for the ball head turning tool, it refers to the center of a part of the ball head; for the lathe turning tool, it is the fingertip knife; for the twist Drill refers to the drill tip; for wire-level laser cutting CNC lathes, it refers to the focus of the wire-level pivot and the surface of the part. When the tool needs to be changed in the whole process of processing, the tool change point should be required, and the position of the tool change point should be set according to the standard that the workpiece, fixture and CNC lathe should not be damaged during tool change.