Numerical control technology originated from the needs of the aviation industry. In the late 1940s, a helicopter company in the United States proposed it.
The initial idea of CNC machine tools, in 1952, the Massachusetts Institute of Technology developed a three-coordinate CNC milling machine. In the mid-1950s, this CNC milling machine was used to process aircraft parts. In the 1960s, the CNC system and programming work became increasingly mature and perfect. CNC machine tools have been used in various industrial sectors, but the aerospace industry has always been the largest user of CNC machine tools. Some large aviation factories are equipped with hundreds of CNC machine tools, among which cutting machine tools are the main ones. CNC machining parts include the overall wall panels, girders, skins, bulkheads, propellers of aircraft and rockets, mold cavities of casings, shafts, discs and blades of aero-engines, and special-shaped cavity surfaces of liquid rocket engine combustion chambers, etc. . In the initial stage of the development of CNC machine tools, the CNC machine brand with continuous trajectory were mainly used, and the continuous trajectory control was used.
Continuous trajectory control, also known as contour control, requires the tool to move on a specified trajectory relative to the part. In the future, we will vigorously develop point-to-point control CNC machine tools. Point control means that the tool moves from a certain point to another point, as long as it can reach the target accurately in the end regardless of the moving route.
CNC Machining, also known as CNC machine tool processing, is a popular processing method widely adopted by many CNC processing manufacturers, especially some machinery and equipment manufacturing companies. So why can CNC machining excel in many processing methods, why choose CNC processing? What advantages does it have?
- CNC Machining VS 3D Printing,CNC Machining is a multi-axis linkage centralized processing method. It integrates various processing methods and technological processes on one machine tool. According to the tool table and CNC tool equipped with the CNC processing core, it depends on the specific working conditions and depends on the program. The process replaces the CNC blades required by the process, reduces the area occupied by the machine tool, saves space for the CNC processing workshop, reduces the intermediate processing stages, saves time, effort and effort, and improves processing efficiency and quality.
- CNC processing is an intelligent processing method. The whole processing process does not require manual operation of CNC blades, and the level of automation technology is also very high. The technical level requirements for operators are low, and the labor efficiency of CNC processing plants is also reduced. The quality of parts processed by CNC is more stable, and the processing efficiency is further improved.
- Compared with transmission system machine tools, CNC machining has stronger coordination ability, higher efficiency, stronger adaptability to parts, higher rigidity, and can be well integrated into the intense market competition in the sales market. Strengthen the overall strength of the manufacturer’s processing.
- The strength of CNC processing is very strong, and it can accurately process various products with different profiles, especially suitable for applications that cannot be damaged, product development, and urgently needed precision casting processing.
Significance and characteristics of CNC machining technology
From the very beginning, the CNC machine tool selects the aircraft parts with complex surfaces as the processing object, and solves the key problem that is difficult to solve by ordinary processing methods.
The biggest feature of CNC machining is the use of perforated belts (or magnetic tapes) to control machine tools for automatic processing. Due to the different characteristics of aircraft, rockets and engine parts: aircraft and rockets have zero parts, large component sizes and complex shapes; engine parts have small component sizes and high precision. Therefore, the CNC machine tools selected by aircraft, rocket manufacturing departments and engine manufacturing departments are different. In aircraft and rocket manufacturing, large CNC Machining machines with continuous control are mainly used, while in engine manufacturing, both continuously controlled CNC machine tools and point-controlled CNC machine tools are used (such as CNC drilling machines, CNC boring machines, machining centers, etc.) .
CNC machine tools generally have tool holders and tool magazines that can automatically change tools. The tool change process is automatically controlled by the program, so the process is relatively concentrated. Process concentration brings huge economic benefits:
- ⑴Reduce the floor area of the machine tool and save the workshop.
- ⑵ Reduce or eliminate intermediate links (such as intermediate inspection of semi-finished products, temporary storage and transportation, etc.), which saves time and manpower.
When CNC machine tools are processed, there is no need to manually control the tool, and the degree of automation is high. The benefits are obvious.
- ⑴ Lower requirements for operators:A senior engineer of an ordinary machine tool cannot be trained in a short period of time, but the training time of a CNC worker who does not need programming is extremely short (for example, a CNC lathe worker only needs one week, and can also write simple machining programs). Moreover, the parts processed by CNC workers on CNC machine tools have higher precision and save time than the parts processed by ordinary workers on traditional machine tools.
- ⑵Reduce the labor intensity of workers: During the processing process, CNC workers are excluded from the processing process most of the time, which is very labor-saving.
- ⑶Stable product quality: The processing automation of CNC machine tools eliminates human errors such as fatigue, carelessness, and estimation of workers on ordinary machine tools, and improves product consistency.
- ⑷ High processing efficiency: The automatic tool change of CNC machine tools makes the processing process compact and improves labor productivity.
Although the traditional general-purpose machine tool has good flexibility, it is inefficient; while the traditional special-purpose machine tool has high efficiency, but it has poor adaptability to parts, high rigidity, and poor flexibility. It is difficult to adapt to the fierce competition brought about by the market economy. Products are frequently modified. As long as the program is changed, new parts can be processed on the CNC machine tool, and it can be operated automatically, with good flexibility and high efficiency, so the CNC machine tool can well adapt to market competition.
The machine tool can accurately process various contours, and some contours cannot be processed on ordinary machine tools. CNC machine tools are especially suitable for the following occasions:
- Parts that are not allowed to be scrapped.
- Development of new products.
- Processing of urgently needed parts.
Numerical control technology has a far-reaching impact on the implementation of automatic control operations(As cnc machining bicycle parts). Now the industrial level of a country depends on how its manufacturing industry is.