Everything you want to know about thread milling is here!
With the popularization of CNC machine tools, the application of thread milling processing technology in the machinery manufacturing industry is increasing. Thread milling is through the three-axis linkage of the CNC machine tool, and the thread milling cutter is used for helical interpolation milling to form the thread. The cutter makes a circular motion on the horizontal plane, and moves linearly by one pitch in the vertical plane. Thread milling has many advantages such as high processing efficiency, high thread quality, good tool versatility, and good processing safety.
When milling threads, cooling is also crucial. It is recommended to use machine tools and tools with internal cooling function. When the tool rotates at high speed, the external coolant is not easy to enter under the action of centrifugal force. In addition to cooling the tool well, the internal cooling method is more important in that the high-pressure coolant helps to remove chips when machining blind hole threads. Ensure smooth chip evacuation. In addition, when selecting a thread milling tool, specific processing requirements should be considered comprehensively, such as production batch, number of screw holes, workpiece material, thread accuracy, size specifications and many other factors, and the tool should be selected comprehensively.
Thread Milling in Practice
Due to the many advantages of thread milling, many manufacturing enterprises have widely adopted the thread CNC milling process. When processing the nozzle thread of a complex part of an engine, after experimental research, the thread milling method has also been used, and good results have been achieved. The following is a brief introduction to this process and process.
1) Characteristics of parts and processing difficulties
A complex part is an important part on the engine. If the thread part of the nozzle adopts turning threads, the main body of the part and the nozzle are not the same rotation center, which brings certain difficulties to the clamping and positioning, but the method of milling the thread is used. It can be easily clamped and processed.
2) Selection of tools
In thread milling, three-axis CNC machine tools and thread milling tools are two essential elements. Several common thread milling cutter types are described below.
Cylindrical thread mill
The helical lift of the cylindrical thread milling cutter is realized by the machine tool movement. Due to this special structure, the tool can process both right-handed and left-handed threads, but it is not suitable for the processing of larger pitch threads. It is suitable for milling small and medium-diameter threads, with stable cutting and high durability. The disadvantage is that the manufacturing cost of the tool is high and the price is expensive.
Machine-clamped thread mills and inserts
Machine-clamped thread mills are suitable for larger diameter (eg 25mm) threading. Its characteristics are that the blade is easy to manufacture and the price is low. The advantage of a machine-clamped thread mill is that it is easy to change inserts, which reduces machining costs.
Combined multi-station special thread boring and milling cutter
The special feature of the combined multi-station thread boring and milling cutter is that it can complete the multi-station processing at one time, which can save auxiliary time such as tool change and significantly improve the productivity. The combined tool can process the workpiece in one time and need to process the internal thread, chamfer and platform.