CNC machining has stricter requirements on the rigidity, precision, durability and dynamic balance performance of cutting tools. The selection of cutting tools should pay attention to the structural and technological analysis of the workpiece, combined with comprehensive considerations such as the processing capabilities of the CNC machine tool, the workpiece material, and the process content. The structural forms of CNC machine tool tool holders are divided into two types: integral type and modular type. The working part of the integral tool holder for clamping the tool is integrated with the shank used for installation and positioning on the machine tool. This kind of tool holder has poor adaptability to changes in machine tools and parts. In order to adapt to the change of parts and machine tools, users must stock tool holders of various specifications, so the utilization rate of tool holders is low. The modular tool system is a more advanced tool system in which each tool holder can be assembled from various series of modules. According to different processing parts and machine tools, different assembly solutions are adopted to obtain a variety of tool holder series, thereby improving the adaptability and utilization rate of the tool holder.
The selection of tool handle structural form should take into account both technological advancement and economic rationality:
① For some simple tools that are used repeatedly for a long time and do not need to be assembled, it is better to be equipped with an integral tool handle, so that the tool has good rigidity and is cheap (such as end mill handles, spring chuck handles and drill handles used to process the outer contour of parts). chuck, tool holder, etc.);
② When processing multiple varieties and small batches of parts with frequently changing hole diameters and hole depths, modular tool holders should be used to replace a large number of integral boring tool holders to reduce processing costs;
③ For many CNC machine tools, especially when the end of the machine tool spindle and the tool changing manipulator are different, it is advisable to use modular tool holders. Since the intermediate modules (connectors) and working modules (tool-mounting modules) used by each machine tool can be used in common, equipment investment can be greatly reduced and tool utilization can be improved. In order to improve processing efficiency, high-efficiency tools and tool holders should be used as much as possible. For example, a double-edged boring tool holder can be used for rough boring, which can not only improve processing efficiency but also help reduce cutting vibration; a powerful spring chuck can not only hold straight-shank tools, but also can hold tools with holes through adapters. .
For typical workpieces with large batches and complex processing, composite cutting tools should be used as much as possible. Although composite cutting tools and tool holders are relatively expensive, using composite cutting tools for processing on a machining center can combine multiple processes into one process and be completed by one tool, which is beneficial to reducing processing time and the number of tool changes, and significantly improving production efficiency. . For some special parts, specially designed composite tool holders can also be considered.