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Undoubtedly, in recent years, the biggest hot spot of new manufacturing technology is high-speed processing technology. According to the latest technological research, high-speed machining technology can greatly improve product quality, reduce production costs and shorten production cycle by simplifying production processes and procedures, reducing follow-up processing workload, improving processing efficiency and improving surface quality. High-speed machining technology also puts forward new special requirements for numerical control and CAM.
High-speed machining uses small cutting depth, small cutting quantity and high feed speed. The general cutting speed of characteristic machining whch is called F value, is more than 10 times that of traditional machining. F value can reach 2000-8000mm/min. Under the condition of high-speed feeding, once the cutting and geometric interference occur, the consequences will be catastrophic. Therefore, security requirements are the most important. The traditional CAM system relies on manual or semi-automatic anti-over-cutting processing mode, and does not fundamentally eliminate the occurrence of over-cutting. There is no safety guarantee depending on the carefulness and responsibility of operators. So it can not meet the basic requirements of high-speed machining safety.
High-speed machining requires the smoothness of tool path and avoids sharp corner of tool path path (tool path suddenly turning). We should also try our best to avoid empty cutting, cut-in or cut-out. Therefore, CAM system is required to have intelligent analysis and processing function based on residual model, tool path smoothing function, optimization processing function in line with high-speed processing technology and feed optimization processing function (cutting optimization processing). CAM should support the latest NURBS programming technology in order to adapt to the high-end CNC system of high-speed processing equipment.
Efficiency is reflected in two aspects:
High efficiency of programming: The technological requirement of high speed machining is much higher than that of traditional NC machining, and the length of tool path is hundreds times longer than that of traditional machining. Generally speaking, the programming time is much longer than the processing time. Therefore, programming efficiency has become one of the key factors affecting the overall efficiency. The traditional CAM system adopts the programming method oriented to local surface. The system can not automatically provide process features, and the programming is very complex. This requires programmers to have a high level of use skills in addition to the technical level. There is an urgent need for a new generation of CAM system with high-speed machining knowledge base, high degree of intelligence, oriented to the overall model.
Optimized tool path ensures high efficiency of NC machining, such as intelligent programming based on residual model can effectively avoid empty cutter, feed optimization processing can improve cutting efficiency by 30%.
In summary, the CAM system today has contributed a lot to the development of modern manufacturing industry. However, there is a huge contradiction with the actual requirements in production management and operation. In terms of structure and function specialization, there is a serious inconsistency with the requirement of system integration under the network. Basic processing methods seriously hinder the improvement of intelligence and automation. All these make the birth and development of a new generation of CAM necessary. The great success of object-oriented and feature-oriented modeling in CAD technology provides a reference model for the development of new generation of CAM. Network technology provides the possibility for the specialization separation and system integration of CAM. Through the above analysis, the outline of a new generation of CAM system has emerged.
