Founded in 1958, AVIC Xi'an Aircraft Industry Co., Ltd. (hereinafter referred to as 'Xifei') is an important base for the development and production of large and medium-sized military and civilian aircraft in China. It has developed and produced more than 20 types of aircraft in aviation components. Among the products, Boeing, Air France and other world giants are leading suppliers. In 2017, Xifei’s revenue exceeded 20 billion yuan for the first time. In the economic scale and comprehensive strength, it has become a aviation industry in China and the world. The backbone that cannot be ignored.
In just a few decades, we can achieve such dazzling achievements. This is inseparable from Xifei’s fear of challenge and the spirit of change. Under the new industrial revolution and the upgrade of aviation equipment, Xifei’s The leadership team decisively realized that we must seize opportunities in the new round of technology and industrial revolution, meet the challenges, take the lead in development, and vigorously promote the transformation of manufacturing methods with 'intelligent manufacturing' as the core.
'To achieve smart manufacturing and increase productivity, the word 'coordination' is essential. Aircraft manufacturing has a large number of production departments, from designers, manufacturers, suppliers, to specialized production units and airlines, Indispensable. Only by optimizing various manufacturing resources and selecting high-quality and reliable suppliers can we complete production tasks to meet the needs of customers' markets, thus helping the long-term development of the company. 'Xifei Lean Processing Center, a person in charge said, 'In recent years, Xifei Lean Center has continuously improved the processing efficiency of our titanium aerospace components and the comprehensive performance of the workpiece through various optimization methods. Among them, it is one of the most important measures to select excellent tool suppliers according to their actual needs. Seco's complete range of products offers efficient tooling and solutions for a wide range of aerospace parts, which is in line with our current needs.'
Aerospace parts generally have the dual processing characteristics of materials and structures. The high cost of machining tools, the difficulty in ensuring the processing quality and processing efficiency are the challenges that are easily encountered in production. The titanium alloy structural parts are even more so. The development of modern aircraft design technology, It provides a broad space for the development of titanium alloys with superior comprehensive performance. At the same time, in the face of the complex design trend of titanium alloy structure, the overall structure, deep cavity structure, thin-wall structure, etc. are widely used for tool selection and The determination of the cutting method poses a serious challenge. Xifei has always stood at the forefront of advanced manufacturing. The Lean Center is constantly innovating the processing of titanium alloy parts. 'In our technical team, we have developed different material properties and geometric characteristics for aerospace titanium alloy structural parts. After the tool selection method and cutting strategy, Seco can always provide the corresponding products and solutions in the first time, and successfully achieve the workpiece machining accuracy and processing efficiency requirements, and also effectively reduce the tool loss. ' The person in charge added.
Complex cavity is preferred for efficient roughing tools
The irregular complex cavity is a typical structure of aerospace parts. For the rough machining of the complex cavity of the Xifei titanium alloy, the lean center technology optimization team believes that the large feed tool is the best tool type.
The relationship between the radius of the tool arc bottom edge and its maximum cutting thickness is:
In the formula:
R——the radius of the bottom edge arc;
Ap - milling depth;
Fz - the amount of feed per tooth.
It can be seen from the above formula that when the cutting depth is increased, the radius of the arc edge can be increased, the lead angle can be reduced to maintain a thin cutting thickness, the tool life can be improved, and the processing time can be shortened.
The large feed tool can achieve a higher feed rate. As shown in Figure 1, the large feed tool uses a large arc edge radius compared to the conventional end mill, and the smaller lead angle design reduces the axial cut. Deep, reduced cutting thickness. This large feed milling method for thinning chip thickness can effectively reduce the load of the main cutting edge, while the chip with very small thickness can also take a lot of cutting heat, improve tool durability and shorten Processing time. This advantage is also very suitable for rough machining of complex cavities.
Figure 1 Comparison of large feed tool and traditional end mill
In the complex cavity roughing process of Xifei Lean Center, Seco provided an indexable large feed milling cutter, which not only helped Xifei achieve high cutting speed and feed speed in machining, due to its large The smaller milling depth brought by the feed milling method can also achieve a more uniform milling allowance, which is conducive to stable milling of subsequent machining.
Plungers are the first choice for deep groove machining
For the deep groove machining of aviation titanium alloy structural parts, due to the difficult processing characteristics of the material itself and the geometric characteristics of the deep groove cavity and the corner angle, the precision and stability of the machining are very difficult to guarantee, which once plagued us. After understanding our needs and difficulties, we gave the solution of the plunge-cutting tool, which achieved good results and far exceeded our expectations. 'The person in charge of the Lean Center said.
Figure 2 Typical structure of the plunge cutter
Plunge milling is an efficient machining method for deep cavity or corner. For complex cavity deep cavity machining, corner machining and other problems, plunge milling technology has a unique advantage. 'In actual machining, plunge milling and traditional milling Very different, plunge milling uses the end of the tool for cutting, not the side, which mainly produces axial forces. The plunge cutter can be used in applications where the tool overhang is large, and the toughness is good in deep groove machining or difficult-to-machine materials. Blade material and sharp groove shape can help customers achieve good production efficiency, processing effect and economic advantage. 'Jia Jianping from Shangao technical team added.
Figure 3 Example of plunge milling tool processing
Round insert milling cutters increase machining efficiency with flexibility
In order to better promote the processing of Xifei titanium alloy, for the multi-type surface features existing in aerospace structural parts, Seco adopts a round-blade milling cutter that can adapt to various types of surface processing to improve processing efficiency.
Figure 4 Typical round insert milling cutter
'Shan Gao's round inserts have high strength due to their unique geometric angle, which is very suitable for the processing of difficult materials such as titanium alloy, and can achieve high metal removal rate and tool life. 'Xifei Lean Center is responsible for The person introduced.
'Circular insert milling cutters are also used in many types of cutting methods, such as circumferential interpolation and helical interpolation ramp milling, square shoulder milling, milling, plunge milling and ramp milling, which are the most flexible tools in 3D milling.' Jia Jianping added.
Different needs
Different parts and structures have different requirements and priorities in processing. For simple contours or cavity structures, the economics of processing cannot be ignored. For slotting, the safety under strict standards is It's important. 'Shan Gao's technical team will communicate with us in depth before giving each solution, understand our processing needs, and truly respond to different needs. 'The person in charge of Lean Center said.
In the contour or simple cavity structure processing, Xifei Lean Center selected Shangao corn milling cutter. Corn milling cutter can not only achieve large depth of cut, large cutting width and powerful milling, but also greatly increase cutting force and cutting efficiency. What's important is that in the actual processing, the corn milling cutter can use various geometrical blades and each blade can be indexed multiple times, helping the lean center to minimize the cutting cost of rough machining of large titanium alloy parts.
Figure 5 corn milling cutter
The cost of aviation components is very high, and the safety in the production process is very important. In order to match the strength of its own powerful products, Xifei Lean Center has extremely strict requirements for the slotting of titanium alloys, and this is precisely the accumulated experience. The mountain height can be provided. For the geometry of the narrow cavity of the Xifei Aviation Titanium structural parts, the JCO710 corrugated milling cutter developed by Seco offers long tool life and high machining safety, which is very suitable for large shafts. High-efficiency roughing of deep-cut stainless steel and titanium alloys, used in the processing of large parts in the aerospace industry, to achieve good results.
Figure 6 corrugated milling cutter
The development of a new generation of aviation equipment and the application of a large number of new materials, new structures, and new technologies have placed higher demands on aviation manufacturing. Facing opportunities and challenges, Xifei will continue to innovate with such excellent suppliers as Seco. , constantly changing, contributing to building a new era of aviation power.
Text / Yin Jia, Bai Hao, Aviation Industry West Fly