Spiral milling process
Compared with traditional drilling, spiral milling uses a completely different machining method. The spiral milling process is composed of two movements: the "rotation" of the spindle and the "revolution" of the spindle around the center of the hole. This special movement determines the advantages of spiral milling.
Firstly, the trajectory of the tool center is a spiral line rather than a straight line, meaning that the tool center no longer coincides with the center of the hole being machined, which is an eccentric machining process. The diameter of the tool is different from the diameter of the hole, which breaks through the limitation of traditional drilling technology that one tool can process holes of the same diameter, and realizes the processing of a series of diameter holes with a single diameter tool. This not only improves processing efficiency, but also greatly reduces the number and types of stored knives, reducing processing costs.
Secondly, the spiral milling process is an intermittent milling process, which is beneficial for tool heat dissipation and reduces the risk of tool wear and failure caused by temperature accumulation. More importantly, compared to traditional drilling, the spiral milling process has made significant improvements in the use of coolant. The entire milling process can be cooled using trace lubrication or even air cooling, making it a green and environmentally friendly process.
Thirdly, the eccentric machining method allows sufficient space for chips to be discharged from the hole groove, and the chip discharge method is no longer the main factor affecting the quality of the hole. It can be seen that this technology has broad development space and good market prospects, but as a new processing method, its processing mechanism needs further research and exploration.
The advantages of spiral milling holes
(1) Improve the quality of machining holes and tool life.
Compared to traditional drilling techniques, spiral milling significantly improves the quality and strength of the holes; Spiral milling holes belong to intermittent cutting, and the lower milling force makes the processed holes burr free; The diameter of the tool is smaller than that of the hole, allowing chips to be smoothly discharged and significantly reducing the roughness value of the hole surface; When processing composite materials, it eliminates the problems of delamination, peeling, and low surface quality of holes caused by tool tip passivation in traditional drilling.
(2) Shorten the development cycle and save processing costs.
The use of spiral milling technology in the manufacturing of aircraft or other heavy machinery will greatly shorten the research and development cycle and reduce costs.
By using spiral milling technology, holes of different diameters and complex shapes can be machined with the same tool. Due to the superiority of its processing method, it can save traditional tasks such as countersunking and reaming. This means that the types and models of cutting tools used for machining holes will continue to decrease in the future. From the perspective of the entire development cycle, the use of spiral technology can reduce many processes (such as deburring, reaming, removing coolant from different holes after disassembly, and then assembling), greatly shortening the processing cycle.
(3) Highly automated.
Realizing a higher degree of automation is also a way to reduce processing costs. Due to the low milling force of the spiral milling process, this technology can only be applied in industrial robot devices. Due to the fragility of industrial robot devices and the excessive axial force of traditional drilling, traditional drilling cannot be applied to such devices.
(4) Promote the use of new materials.
The use of new materials in aircraft components is a clear development trend, and new materials such as titanium alloys and composite materials have been widely applied. The development and use of new materials require suitable processing technology support. In terms of hole machining, research has shown that compared to traditional drilling techniques, spiral milling technology has significant advantages.
The spiral milling process only requires one tool to machine holes of different diameters and high quality, reducing tool changing time and saving precision machining processes, greatly improving work efficiency. Given the advantages of spiral milling technology, many enterprises, especially in the aviation and mold industries, have begun to apply it to practical production. With the promotion and application of this technology, traditional drilling tools will gradually be phased out, while new milling devices will increasingly appear in mechanical machining workshops.
