How to scientifically select CNC cutting tools for CNC machining?

How to scientifically select CNC cutting tools for CNC machining?

How to scientifically select CNC cutting tools for CNC machining? Let's take a brief look together.

1. Principles for selecting CNC machining tools. The tool life is closely related to the cutting amount. When setting cutting parameters, it is necessary to first choose the appropriate tool life, and a reasonable tool life must be determined based on optimization objectives. There are generally two types of tool life: maximum productivity tool life and minimum cost tool life. One depends on the goal of minimizing working time, and the other depends on the goal of minimizing process costs.

When selecting the tool life for CNC machining, the following points can be considered based on the complexity of the tool, manufacturing and grinding costs: the life of complex and high-precision tools should be higher than that of single blade tools. For clamp type indexable tools, due to the short tool switching time, in order to fully utilize cutting performance and improve work efficiency, a lower tool life can be selected. Usually used for 15-30 minutes. For multi tool machines, combination machines, and automated machining tools with relatively complex tool installation, tool replacement, and tool adjustment, the tool life must be higher, especially to ensure tool reliability. If the productivity of a workshop process limits the overall productivity improvement of the workshop, it is necessary to choose a process with a lower tool life for that process. If the overall factory expenses shared within a specific process unit time are relatively large, the tool life should also be chosen to be lower. In order to avoid changing the tool midway during large-scale precision machining after completing at least one tool path and cutting, the tool life should be determined based on the precision and surface roughness of the parts. CNC machining places higher demands on cutting tools than ordinary machine tool machining methods. The cockpit is not only good and has high accuracy, but also requires installation and adjustment for dimensional stability, durability, damage, and performance, meeting the efficiency requirements of CNC machine tools. The tools selected in digital control machines use tool materials suitable for high-speed cutting, such as high-speed steel and ultrafine hard alloys, typically using rotatable blades.

2. Selection of CNC turning tools. The commonly used CNC turning tools include general segmentation turning tools, pointed turning tools, circular turning tools, and three types. Formed wire cutters, also known as template wire cutters, determine the contour shape of the machined parts entirely by the shape, bolts, and size of the turning tool. In CNC turning, typical forming lines include small radius arc turning tools, non rectangular groove cutting tools, thread cutting tools, etc. In digital control machining, the use of forming wire cutters should be minimized or avoided as much as possible. Sharp blade is a linear cutting tool characterized by a straight cutting edge. The tip of this type of knife is composed of circular turning tools around 900, left and right end turning tools, groove (cutting) turning tools, various outer circles with small chamfers on the tip, and straight main and auxiliary cutting edges (such as inner hole turning tools). The selection method for geometric parameters (mainly geometric angles) of pointed turning tools is roughly the same as conventional turning, but it needs to be comprehensively considered in combination with the characteristics of CNC machining (such as machining path, machining interference, etc.), and at the same time consider the strength of the tool tip itself.

The second is the circular arc turning tool. Circular arc turning tool is a line tool characterized by circular cutting edges with small silhouette errors. Every point on the curved edge of this turning tool is the tip of the curved turning tool. In this case, the tool position must be at the center of the arc, not on the arc. Circular arc turning tools can be used for turning inner and outer surfaces, especially suitable for turning various smooth connecting (concave) surfaces. When selecting the arc radius of the turning tool, the arc radius of the cutting edge of the two-point turning tool must be less than or equal to the minimum curvature radius of the concave contour of the part. The processing depth should not be too small. Otherwise, not only will it be difficult to manufacture, but also if the tool tip strength is too weak or the tool cooling ability is weak, it may cause damage to the turning tool.

Precision machining