How to choose CNC machining tools
Machining center professionals pointed out: The selection of Cnc Machining center tools is carried out under the human-computer interaction state of CNC programming. The correct selection of tools and tool holders should be based on the processing capacity of the machine tool, the properties of the workpiece material, the processing procedure, the cutting amount and other related factors. The general principle of tool selection is: easy installation and adjustment, good rigidity, high durability and precision. On the premise of meeting the processing requirements, try to choose a shorter tool holder to improve the rigidity of tool processing.
When selecting a tool, the size of the tool must be adapted to the surface size of the workpiece to be processed. In production, end mills are often used to process the peripheral contours of plane parts; when milling planes, carbide blade milling cutters should be selected; when processing bosses and grooves, high-speed steel end mills should be selected; rough surface or rough machining When drilling holes, you can choose corn milling cutters with carbide inserts; for the processing of some three-dimensional profiles and variable bevel contours, ball-end milling cutters, ring milling cutters, tapered milling cutters and disc milling cutters are often used.
When performing free-form surface machining, since the end cutting speed of the ball-end tool is zero, in order to ensure the machining accuracy, the cutting line spacing is generally very dense, so the ball end is often used for surface finishing. The flat-end tool is superior to the ball-end tool in terms of surface processing quality and cutting efficiency. Therefore, as long as it is guaranteed not to cut, whether it is roughing or finishing of curved surfaces, flat-end tools should be preferred. In addition, the durability and accuracy of the tool has a great relationship with the price of the tool. It must be noted that in most cases, the selected tool increases the tool cost, but the resulting increase in processing quality and efficiency , You can greatly reduce the overall processing cost.
On the machining center, various tools are installed in the tool magazine, and the tool selection and tool change actions are carried out at any time according to the program regulations. Therefore, standard tool holders must be used so that standard tools used in drilling, boring, expanding, milling and other processes can be quickly and accurately installed on the spindle or tool magazine of the machine tool. The programmer should understand the structure size, adjustment method and adjustment range of the tool holder used on the machine tool in order to determine the radial and axial dimensions of the tool during programming. At present, my country’s machining center adopts the TSG tool system, and its tool holders have two types: straight shank (three specifications) and tapered shank (four specifications), including a total of 16 tool holders for different purposes.
In economical CNC machining, since the sharpening, measurement and replacement of tools are mostly performed manually, which takes a long time to assist, it is necessary to arrange the order of the tools in a reasonable manner. Generally, the following principles should be followed:
Minimize the number of tools;
One: After a tool is clamped, all processing parts that it can perform should be completed;
Rough and finishing tools should be used separately, even if they are tools of the same size;
Milling before drilling;
2: Perform surface finishing first, then two-dimensional contour finishing;
Three: Where possible, the automatic tool change function of cnc machine tools should be used as much as possible to improve production efficiency.