Three points to be aware of when selecting hardware parts fo
source：未知
The tool selection of hardware parts processing is one of the important contents in the CNC machining process, which not only affects the efficiency of CNC machine tool processing, but also directly affects the processing quality of parts. Since the spindle speed and range of CNC machine tools are much higher than ordinary machine tools, and the spindle output power is large, compared with the traditional machining methods, higher requirements are imposed on CNC machining tools, including high precision, high strength and rigidity. Good, durable, and required dimensional stability, easy installation and adjustment, the characteristics of the CNC machine spindle drive system. This requires reasonable structure of the tool, standardization of geometric parameters, and serialization. CNC tooling is one of the prerequisites for improving machining efficiency. Its choice depends on the geometry of the part being machined, the material state, the rigidity of the tool and the tool selected by the machine tool. The following aspects should be considered:
(1) Select the tool according to the cutting performance of the part material. For cars or milled high-strength steels, titanium alloys, and stainless steel parts, it is recommended to select indexable carbide tools with good wear resistance.
(2) Select the tool according to the processing stage of the hardware parts. That is, the roughing stage is mainly to remove the margin. The tool with better rigidity and lower precision should be selected. The semi-finishing and finishing stages should be used to ensure the machining accuracy and product quality of the parts. The durability should be high and the precision should be selected. For high tools, the tools used in the roughing phase have the lowest precision and the tools used in the finishing phase have the highest precision. If the same tool is selected for roughing and finishing, it is recommended to use the finishing tool to eliminate the roughing tool, because the tool wear condition of the finishing process is mostly the slight wear of the blade, the coating wear and light, and the use will affect the finishing. Processing quality, but less impact on roughing.
(3) Select the tool and geometric parameters according to the characteristics of the machining area of ??the CNC lathe. If the part structure allows, the tool with large diameter and long diameter ratio should be selected; the end mill edge of the thin-walled and ultra-thin wall parts should have sufficient centripetal angle to reduce the cutting of the tool and the cutting part. force. When processing parts such as aluminum and copper, you should select an end mill with a slightly larger front corner and the number of teeth should not exceed 4 teeth.
When selecting a tool, the size of the tool should be adapted to the surface size of the workpiece being machined. In the production, the peripheral contour of the plane parts is often processed by an end mill; when milling the plane, the cemented carbide insert milling cutter should be selected; when the boss and the groove are machined, the high-speed steel end mill is selected; the surface of the rough metal processing is rough or rough. When milling holes, corn milling cutters with carbide inserts can be selected. For some three-dimensional and variable bevel contours, ball-end milling cutters, ring milling cutters, conical milling cutters and disc milling cutters are often used. .
In the free-form surface machining, since the cutting speed of the end of the ball-end tool is zero, in order to ensure the precision of the numerical control machining, the cutting distance is generally small, so the ball-end milling cutter is suitable for the finishing of the curved surface. The end mill is far superior to the ball end mill in both surface quality and machining efficiency. Therefore, when roughing and semi-finishing the surface, try to select the end while ensuring that the part is not cut. Milling cutter. In addition, the durability and accuracy of the tool are highly dependent on the tool price. It must be noted that in most cases, the choice of a good tool increases the tool cost, but the resulting processing quality and processing efficiency are improved. , can make the entire processing cost greatly reduced.
In the machining center, all the tools are pre-installed in the tool magazine, and the corresponding tool change is performed by the tool selection and tool change commands of the NC program. The corresponding standard shank for the machine tool system specification must be selected so that the CNC machining tool can be quickly and accurately mounted to the machine spindle or returned to the tool magazine. The programmer should be able to understand the structure size, adjustment method and adjustment range of the tool holder used in the machine tool to ensure that the radial and axial dimensions of the tool are determined during programming, and the order of the tools is arranged reasonably.
