How to determine the feeding route in rough machining and metal machining of CNC turning.
CNC turning rough machining feed route
The commonly used feeding routes for rough machining of workpiece by CNC turning process mainly include "rectangular" circular feeding route, circular feeding route along contour shape isometric line, stepped cutting route and bidirectional cutting feeding route.
Among them, the "rectangular" circular feed route is designed by using the rectangular circular function in the CNC system.
The circular feed route along the contour shape isometric line is a feed route that uses the closed compound cycle function in the CNC system to control the turning tool to cycle along the contour of the workpiece.
The two-way cutting feed route is a feed processing route that uses the characteristics of CNC lathe processing and uses the method of simultaneous feeding in both horizontal and radial directions along the contour of the workpiece.
Feed route of CNC turning finishing
The CNC turning process is used for the precision machining of the workpiece. The commonly used feed routes mainly include the feed route of the part forming contour, the feed route that needs to be changed during machining, and the feed route that is planned according to the machining accuracy of each machining surface. In addition, during the cutting process, attention should be paid to the selection of the position of the cutting tool cut in, cut out and the tool receiving point.
When arranging the fine turning feed route for one tool or multi tool machining, the final forming contour of the part should be completed by the last tool continuously, and the feeding and withdrawal positions of the machining tools should be fully considered. Therefore, when designing the feeding route of part forming contour, try not to arrange cutting in, cutting out, tool changing and pause in the continuous contour trajectory, so as to avoid causing elastic deformation, surface scratch and other defects to the workpiece.
If the tool must be changed during the processing of the workpiece, the sequence of each machining tool and how to connect the feeding routes of each machining tool are mainly determined according to the requirements of the work step sequence when designing the feeding route.
The accuracy requirements of each surface of the workpiece are also related to the design of the route. If the accuracy requirements of each processing part of the part are not different, the highest surface accuracy requirements shall prevail, and all processing parts of the part shall be processed by one-time continuous cutting. If the accuracy requirements of each machining part of the part are quite different, the machining surface with close accuracy should be arranged within the tool path of the same turning tool to complete the cutting of the machining part. It should be noted that in the latter case, the parts with lower accuracy requirements should be processed first, and then the parts with higher accuracy requirements should be processed step by step.
If it is necessary to cut in and out the machining tools, the cutting in, cutting out and tool receiving points should be selected as far as possible in the position with empty tool slots or where there are inflection points and corners between the part surfaces. All curves requiring tangent or smooth connection cannot be used as the position of cutting in, cutting out and tool receiving points of machining tools at the connection point.