In the fields of aerospace and high-end intelligent equipment manufacturing, internal precision structural components are often the core difficulty in the research and mass production of complete machines. Unlike conventional mechanical parts, aircraft internal structural components are limited by cabin space and generally adopt lightweight, integrated, and complex one-piece molding designs. They are also the most vulnerable category for many R&D, procurement, and process teams in outsourcing processing.
Many manufacturing companies encounter the same problem: compliant drawing parameters and qualified sample trial production. However, after entering small-scale trial production, there are large fluctuations in part accuracy, excessive form and position tolerances, and poor assembly adaptability, which directly slows down the overall R&D progress of the machine. Fundamentally, it is not that the machining accuracy standards are too high, but rather that most conventional machining processes are unable to adapt to the special structural properties of complex aerospace internal components.
The internal space of aircraft is compact and narrow. In order to balance weight reduction, strength, and installation adaptability, these structural components generally integrate multiple repeated features such as multiple inclined surfaces, irregular cavities, staggered positioning holes, and thin-walled rib plates. Conventional CNC machining processes are difficult to balance accuracy and stability, and the main pain points are concentrated in three points:
Firstly, repeated clamping results in accumulated tolerances. Ordinary three-axis and four axis machining equipment cannot complete multi angle and multi surface one-time machining, requiring repeated flipping, repositioning, and clamping. Each clamping operation will result in slight benchmark deviation, and after multiple stacking, it is easy to exceed the positional tolerance, flatness, perpendicularity and other geometric tolerances, which cannot meet the requirements of aviation grade assembly.
Secondly, thin-walled structures are highly susceptible to cutting deformation. Lightweight aviation parts have thin walls and fine ribs, and commonly used materials such as aluminum alloy and titanium alloy have significant differences in cutting characteristics. During the machining process, problems such as tool vibration, surface vibration patterns, and thin-walled deformation are prone to occur, making it the most difficult process to control in precision machining.
Thirdly, the integration of multiple features doubles the difficulty of the process. The fusion of multiple structures such as curved surfaces, inclined holes, countersunks, and positioning grooves in a single component can disrupt the overall benchmark consistency during the disassembly process. Conventional machining methods are difficult to ensure the uniformity of overall dimensions and positional accuracy.
To consistently produce qualified aviation precision structural components, the key lies not in the quantity of equipment, but in the adaptability of the process plan. The mature processing standards in the industry mainly include four dimensions:
1. Five axis integrated machining technology as the core
Five axis CNC machining can achieve one-time clamping and multi angle linkage machining for aerospace complex structures, multiple inclined surfaces, and deep cavity parts, without the need for repeated flipping and positioning. It eliminates tolerance accumulation from the root, ensures unified part benchmarks, and stable form and position tolerances. It is currently the mainstream essential technology for aerospace complex parts machining.
2. Pre DFM manufacturability process evaluation
The key to processing complex and precise parts lies in the prerequisite of the manufacturing process. A professional process team will optimize the cutting path, cutting parameters, rounded corners, and tool return structure in advance based on material characteristics, part structure, and tolerance requirements, to avoid processing risks such as deformation, tool vibration, and interference, greatly improving the success rate of trial production.
3. Full dimensional high-precision detection and traceability system
Aviation components have strict requirements for quality control, and must rely on high-precision three coordinate detection equipment to comprehensively detect and record key dimensions and form tolerances, achieve full process quality traceability of parts, and meet the quality audit standards of the aerospace supply chain.