I. Preface
CNC machine tools have been increasingly used in modern manufacturing, and they have the advantages that ordinary machine tools cannot match. CNC machine tools mainly have the following features:
1. The transmission chain is short. Compared with the ordinary machine tool, the spindle drive is no longer a motor--belt-gear auxiliary mechanism. Instead, horizontal and vertical feeds are used to drive the two servo motors respectively. , Clutches and other traditional components, greatly reducing the transmission chain.
2. High rigidity, in order to match with the high precision of the numerical control system, the rigidity of the numerical control machine tool is high, so as to adapt to high-precision machining requirements.
3. Lightly drag, the tool holder (workbench) moves using ball screw, small friction, easy to move. Both ends of the bearing support bearings, the pressure angle is larger than the ordinary bearings, they will be equipped with a good selection at the factory; CNC machine lubrication part of the oil mist automatic lubrication, these measures make the CNC machine tools to move light.
1. High degree of automation can reduce the operator's manual labor intensity. The NC machining process is automatically completed according to the input program. The operator only needs to start the tool setting, loading and unloading the workpiece, and changing the tool. During the machining process, the operator mainly observes and supervises the operation of the machine tool. However, due to the high technical content of CNC machine tools, the operator's mental work will increase accordingly.
2. The processing of parts with high precision and stable quality. CNC machine tool positioning accuracy and repeatability are very high accuracy, easier to ensure the consistency of a batch of parts size, as long as the process design and procedures are correct and reasonable, coupled with meticulous operation, you can ensure that the parts get a higher processing accuracy, but also easy to Process quality control.
3. High production efficiency. CNC machine tool processing is able to process multiple machining surfaces once again in the clamping process. Generally, only the first piece is detected. Therefore, many intermediate processes such as marking and dimension detection can be processed at the time of ordinary machine tools at the provincial or provincial level, reducing the auxiliary time. Due to the stable quality of the parts produced by CNC machining, the convenience of follow-up procedures, the overall efficiency is significantly improved.
4. Facilitate the development and modification of new products. CNC machining generally does not require many complicated process equipment. By compiling machining programs, parts with complex shapes and high precision can be machined. When the product is remodeled and the design is changed, it is only necessary to change the program without redesigning the tooling. Therefore, CNC machining can greatly shorten the product development cycle, providing a shortcut for research and development of new products, product improvement, and retrofitting.
5. Can be developed to more advanced manufacturing systems. CNC machine tools and their machining technologies are the basis of computer-aided manufacturing.
6. The initial investment is large. This is due to the high cost of CNC machine tools, the longer first-time preparation cycle, and higher maintenance costs.
7. High maintenance requirements. CNC machine tools are typical products of technology-intensive electromechanical integration. Maintenance personnel need to understand both mechanical and micro-electronics maintenance knowledge while also having better maintenance equipment.
Third, suitable for CNC machined parts
1. The most suitable for multi-type small and medium-sized parts. With the gradual decline in the cost of manufacturing CNC machine tools, now whether domestic or foreign, the processing of large quantities of parts has also emerged. When processing very small batches and single pieces of production, it is optional to shorten the debugging time of the program and the preparation time of the tool.
2. Parts requiring high accuracy. The CNC machine tool has good rigidity, high manufacturing precision, precise tool setting, and easy size compensation, so parts with high dimensional accuracy can be machined.
3. Parts with small surface roughness. In the case of a fixed workpiece and tool material, finishing allowance and tool angle, the surface roughness depends on the cutting speed and the feed rate. Ordinary machine tool is a constant speed, the different diameters of different cutting speeds, such as CNC lathes with constant line speed cutting function, car end surface, different diameters and outer circles can use the same linear speed, to ensure that the surface roughness value is small and consistent. When processing surfaces with different surface roughness, small feedrates are used for surfaces with small roughness, large feedrates are used for surfaces with large roughness, and variability is very good, which is difficult to achieve on ordinary machine tools.
4. Parts with complex contour shapes. Any plane curve can be approximated by a straight line or an arc. The CNC machine tool has a circular interpolation function and can process various complicated contour parts.
Fourth, the use of CNC machine tools management
The use of CNC machine tools requires both the careful use of operators and scientific management. A sound management system and scientific production model are effective means to increase production efficiency.
1. Establish and improve a sound management system, effectively control and supervise the work of relevant personnel of CNC machine tools, so that the whole process of operation and operation of the machine tool is controlled.
2. Strengthen the training of technical personnel and technical worker management personnel. CNC machining training is a long-term work and it is a process of continuous improvement. By training the craftsmen, more simplified NC machining processes can be prepared, the procedures can be simplified, and the processing time can be shortened; the skilled workers can improve the operation skills; the management personnel can better understand the characteristics of numerical control equipment, process control, and implement management with modern production management concepts.
3. Science organization production. Improve the work stoppage and wait for the problem of unbalanced production capacity, increase the operating rate of CNC machine tools, rationally arrange the production cycle, and reasonably allocate production tasks. Using the similarity of parts processing, the parts to be processed are categorized so as to be reasonably arranged in the process preparation, production planning and scheduling, and to increase the balance of equipment production capacity. Scientific production batches will greatly reduce the proportion of machine tool adjustment time and tool preparation time, and can increase batch efficiency.
4. In order to realize the value of CNC machine tools, operators must correctly grasp the operating principles of CNC machine tools. Correctly operate the machine tool according to the machine tool operation procedures; process the parts according to the process and procedure requirements; coordinate the size of the parts, tools, platens, etc. before processing to avoid interference and collision; improve the technical quality, reduce the non-machining time such as loading, correcting, etc.; The auxiliary tools ensure accuracy and reliability.
V. Conclusion
The application of CNC machine tools has become increasingly widespread. How to “manage, use, and maintain†CNC machine tools has become an important issue to be solved. The use of CNC machine tools is not simply the use of equipment, it is a very strong application engineering. Only scientific management, full understanding of the characteristics of CNC machine tools, coordination of the balance of the various production processes in order to truly play its economic benefits.
CNC machine tools have been increasingly used in modern manufacturing, and they have the advantages that ordinary machine tools cannot match. CNC machine tools mainly have the following features:
1. The transmission chain is short. Compared with the ordinary machine tool, the spindle drive is no longer a motor--belt-gear auxiliary mechanism. Instead, horizontal and vertical feeds are used to drive the two servo motors respectively. , Clutches and other traditional components, greatly reducing the transmission chain.
2. High rigidity, in order to match with the high precision of the numerical control system, the rigidity of the numerical control machine tool is high, so as to adapt to high-precision machining requirements.
3. Lightly drag, the tool holder (workbench) moves using ball screw, small friction, easy to move. Both ends of the bearing support bearings, the pressure angle is larger than the ordinary bearings, they will be equipped with a good selection at the factory; CNC machine lubrication part of the oil mist automatic lubrication, these measures make the CNC machine tools to move light.
1. High degree of automation can reduce the operator's manual labor intensity. The NC machining process is automatically completed according to the input program. The operator only needs to start the tool setting, loading and unloading the workpiece, and changing the tool. During the machining process, the operator mainly observes and supervises the operation of the machine tool. However, due to the high technical content of CNC machine tools, the operator's mental work will increase accordingly.
2. The processing of parts with high precision and stable quality. CNC machine tool positioning accuracy and repeatability are very high accuracy, easier to ensure the consistency of a batch of parts size, as long as the process design and procedures are correct and reasonable, coupled with meticulous operation, you can ensure that the parts get a higher processing accuracy, but also easy to Process quality control.
3. High production efficiency. CNC machine tool processing is able to process multiple machining surfaces once again in the clamping process. Generally, only the first piece is detected. Therefore, many intermediate processes such as marking and dimension detection can be processed at the time of ordinary machine tools at the provincial or provincial level, reducing the auxiliary time. Due to the stable quality of the parts produced by CNC machining, the convenience of follow-up procedures, the overall efficiency is significantly improved.
4. Facilitate the development and modification of new products. CNC machining generally does not require many complicated process equipment. By compiling machining programs, parts with complex shapes and high precision can be machined. When the product is remodeled and the design is changed, it is only necessary to change the program without redesigning the tooling. Therefore, CNC machining can greatly shorten the product development cycle, providing a shortcut for research and development of new products, product improvement, and retrofitting.
5. Can be developed to more advanced manufacturing systems. CNC machine tools and their machining technologies are the basis of computer-aided manufacturing.
6. The initial investment is large. This is due to the high cost of CNC machine tools, the longer first-time preparation cycle, and higher maintenance costs.
7. High maintenance requirements. CNC machine tools are typical products of technology-intensive electromechanical integration. Maintenance personnel need to understand both mechanical and micro-electronics maintenance knowledge while also having better maintenance equipment.
Third, suitable for CNC machined parts
1. The most suitable for multi-type small and medium-sized parts. With the gradual decline in the cost of manufacturing CNC machine tools, now whether domestic or foreign, the processing of large quantities of parts has also emerged. When processing very small batches and single pieces of production, it is optional to shorten the debugging time of the program and the preparation time of the tool.
2. Parts requiring high accuracy. The CNC machine tool has good rigidity, high manufacturing precision, precise tool setting, and easy size compensation, so parts with high dimensional accuracy can be machined.
3. Parts with small surface roughness. In the case of a fixed workpiece and tool material, finishing allowance and tool angle, the surface roughness depends on the cutting speed and the feed rate. Ordinary machine tool is a constant speed, the different diameters of different cutting speeds, such as CNC lathes with constant line speed cutting function, car end surface, different diameters and outer circles can use the same linear speed, to ensure that the surface roughness value is small and consistent. When processing surfaces with different surface roughness, small feedrates are used for surfaces with small roughness, large feedrates are used for surfaces with large roughness, and variability is very good, which is difficult to achieve on ordinary machine tools.
4. Parts with complex contour shapes. Any plane curve can be approximated by a straight line or an arc. The CNC machine tool has a circular interpolation function and can process various complicated contour parts.
Fourth, the use of CNC machine tools management
The use of CNC machine tools requires both the careful use of operators and scientific management. A sound management system and scientific production model are effective means to increase production efficiency.
1. Establish and improve a sound management system, effectively control and supervise the work of relevant personnel of CNC machine tools, so that the whole process of operation and operation of the machine tool is controlled.
2. Strengthen the training of technical personnel and technical worker management personnel. CNC machining training is a long-term work and it is a process of continuous improvement. By training the craftsmen, more simplified NC machining processes can be prepared, the procedures can be simplified, and the processing time can be shortened; the skilled workers can improve the operation skills; the management personnel can better understand the characteristics of numerical control equipment, process control, and implement management with modern production management concepts.
3. Science organization production. Improve the work stoppage and wait for the problem of unbalanced production capacity, increase the operating rate of CNC machine tools, rationally arrange the production cycle, and reasonably allocate production tasks. Using the similarity of parts processing, the parts to be processed are categorized so as to be reasonably arranged in the process preparation, production planning and scheduling, and to increase the balance of equipment production capacity. Scientific production batches will greatly reduce the proportion of machine tool adjustment time and tool preparation time, and can increase batch efficiency.
4. In order to realize the value of CNC machine tools, operators must correctly grasp the operating principles of CNC machine tools. Correctly operate the machine tool according to the machine tool operation procedures; process the parts according to the process and procedure requirements; coordinate the size of the parts, tools, platens, etc. before processing to avoid interference and collision; improve the technical quality, reduce the non-machining time such as loading, correcting, etc.; The auxiliary tools ensure accuracy and reliability.
V. Conclusion
The application of CNC machine tools has become increasingly widespread. How to “manage, use, and maintain†CNC machine tools has become an important issue to be solved. The use of CNC machine tools is not simply the use of equipment, it is a very strong application engineering. Only scientific management, full understanding of the characteristics of CNC machine tools, coordination of the balance of the various production processes in order to truly play its economic benefits.