What kind of tool holder do CNC machine tools usually choose?

1) Tool shank structure
The structure of TOOL HOLDER of NC machine tool can be divided into two types: integral mode and modular mode. The working part of the clamping tool of the integral Tool Holder is integrated with the handle used for fixing and positioning on the machine tool. This kind of tool holder has poor adaptability to the transformation of machine tools and parts. In order to adapt to the transformation of parts and machine tools, users must store various specifications of tool holders, so the utilization rate of tool holders is low. Modular cutting tool system is an advanced cutting tool system. Each tool handle can be assembled by a variety of serialized modules. For different parts and machine tools, different assembly schemes can be adopted to obtain a variety of tool shank series, thus improving the adaptability and utilization of tool shank.

The selection of tool holder structure should take into account both advanced technology and economic rationality: 1) For some simple tools which are used repeatedly for a long time and need not be assembled, it is appropriate to equip with integral tool holder, so that the tool is rigid and cheap (such as end milling tool holder, spring chuck tool holder and DRILL CHUCK tool holder for processing the outline of parts, etc.); When many kinds and small batches of parts with varying aperture and hole depth are often used, modular tool holder should be selected to replace a large number of integral boring tool holders and reduce the processing cost. 3. Modular tool holder should be selected for more CNC machine tools, especially for the end of the spindle and the tool changing manipulator. Because the intermediate module (connecting rod) and the working module (tool loading module) used in each machine tool are universal, the investment of equipment can be greatly reduced and the utilization rate of tools can be improved.

2) Tool handle specification
Most CNC tool shanks adopt 7:24 tapered tool shanks, and the corresponding type of pull nail tension structure matches the machine tool spindle. Tool handle has various specifications, commonly used are No. 40, No. 45 and No. 50. At present, ISO7388-1983, GB10944-1989, MAS403-1982, ANSI/ASMEB5.50-1985 and so on are widely used in our country. When choosing the tool shank specifications, the machine tool spindle and manipulator should be considered.

3) Specification quantity of tool handle
The integrated TSG tool system includes 20 kinds of tool holders with hundreds of specifications. Users can select the specifications of tool holders according to the NC processing technology of typical parts processed, which can meet the processing requirements without causing backlog. Considering that a certain number of tool shanks are in pre-adjustment or tool grinding while CNC machine tools are working, the number of tool shanks is usually 2-3 times that of the required tool shank.

4) Tool and handle matching
Attention should be paid to the matching of tool holder and tool, especially when selecting tapping tool holder, attention should be paid to the size of tap drive square head. In addition, choosing single-edge boring cutter on NC machine tool can avoid scratching workpiece during tool withdrawal, but attention should be paid to the position direction of tool tip relative to keyway on tool handle: some machine tools require the same orientation as keyway, while some machine tools require that the orientation of keyway be perpendicular to the orientation of keyway.

5) Selection of efficient and composite tool holders
In order to improve the processing efficiency, high efficiency cutters and tool holders should be selected as far as possible. For example, the double-edged boring tool holder can be used for rough boring, which can not only improve the processing efficiency, but also help to reduce cutting vibration. The strong spring chuck can not only clamp the straight shank tool, but also clamp the Hole-Bearing tool through the connecting rod. For large batch and complex typical workpieces, composite cutting tools should be selected as far as possible. Although the price of composite cutting tools and tool holders is relatively expensive, the use of composite cutting tools in machining centers can combine multiple processes into one process and be completed by a single tool, which is conducive to reducing the processing time and the number of tool changes, and significantly improving production efficiency. For some special parts, special design of composite tool holder can also be considered.

6) Strengthen Tool System Management
As the number of CNC machine tools increases, the number of tool holders will increase dramatically. A flexible manufacturing system with 5 to 8 CNC machine tools has more than 1000 tool shanks. How to make rational and effective use of these tools is the key work of tool management. Its contents include: putting forward purchase or supplementary plan of tool handle; presetting of tool data; scheduling and keeping of tool; judging and controlling tool life, etc.