CNC machining is a kind of process method to process parts on CNC machine tools. CNC machining is consistent with traditional machine tools in general. It is an effective way to solve the problems of variable parts, small batch, complex shape, high precision and realize high efficiency and automatic machining. For a part with high complexity, high precision and need to be processed by CNC machine tools, the following is a brief introduction to the principle of CNC machining process division in Borun Petrochemical.
Process division method
(1) process the parts by clamping and positioning.
Due to the different structural shapes of each part and the different technical requirements of each surface, the positioning methods of each part are different in machining. When machining parts in general, they should be positioned in the inner shape and positioned in the shape when the parts are processed. The process can be divided according to different positioning methods.
(2) processing according to rough and Seiko sequence.
According to the machining accuracy, stiffness and deformation of parts, the process can be divided according to the principle of separation of rough and finish machining, that is, rough machining first, then finish machining. At this time, different machine tools or different tools can be used for processing. Usually in one installation, it is not allowed to finish machining one part of the surface of the part, and then reprocess the other surface of the part.
(3) processing according to centralized process.
In order to reduce the number of tool changes, shorten the running time of empty stroke and reduce unnecessary positioning errors, the machining process of parts can be divided according to the method of using the same tool to centralize the machining process. Use the same tool as much as possible to process all the parts that can be machined, and then replace another tool to process the rest of the part. This method is often used in special CNC machine tools and machining centers.
Two. The method of dividing work steps.
The division of work steps is mainly considered from two aspects: machining accuracy and production efficiency. Different cutting tools and cutting parameters are often needed to process different surfaces in a process. In order to facilitate analysis and description of complex parts, it is subdivided into work steps in the process. The principle of division is:
(1) The same surface is roughed, semi-finished and finished in turn, or all the surface is roughed and then finished separately.
(2) For parts with both milling plane and boring surface, they can be machined by milling plane before boring. By dividing the steps according to this method, the machining accuracy of high holes can be raised. Because the cutting force is larger when milling the plane, parts tend to deform. Milling plane before boring can restore its deformation for a period of time and reduce the influence of deformation on the accuracy of the hole.
(3) divide the steps according to the use of cutting tools. The turning time of the worktable of some machine tools is shorter than that of tool changing. The working steps can be divided according to the tool used to reduce the number of tool changing and improve the machining efficiency.
Two. Ways to improve cutting technology.
(1) design of high speed cutting tools
With the expansion of high-speed machining applications, the research of new tool materials, the improvement of tool design structure, the generation of new NC tool path strategy and the improvement of cutting conditions have also been improved.
(2) manufacture of high speed milling equipment
Ultra high speed cutting technology is the development direction of cutting process, and is also the product of the development of the times. High-speed cutting technology is one of the main development directions of cutting technology. With the development of basic technology, such as technology, microelectronics technology, new materials and new structures, it has advanced to a higher level.
(3) the development of CNC system is progressing smoothly.
Generally speaking, machine tool adaptive control can be divided into process adaptive control and geometric adaptive control, among which process adaptive control is studied more. Intelligent technology is used to realize intelligent decision-making, process adaptive control, error compensation intelligent control, motion trajectory optimization control of complex curved surface machining, fault self-diagnosis, intelligent maintenance and information integration under multi-information fusion, which will greatly improve forming and machining accuracy and manufacturing efficiency.
(4) research and development of special cutting oil
Special cutting oil is a kind of medium which must be used in NC cutting process. It plays the role of lubrication, cooling, cleaning and so on. Due to the continuous improvement of cutting tools, equipment and technology in high-speed cutting, new cutting oil usually uses vulcanized extreme pressure and anti-wear additives as its core component, which can effectively protect the cutting tools and improve the process accuracy in ultra-high-speed cutting process.
