“Differences and Advantages between CNC Machine Tools and General Machine Tools”
In today’s field of mechanical processing, numerical control technology and CNC machine tools occupy a crucial position. In a simple sense, a CNC machine tool is a general machine tool with a numerical control system added, but in fact, it is much more than that. Numerical control technology is the most advanced processing equipment currently used in the mechanical processing industry, covering multiple categories such as CNC lathes, CNC milling machines, CNC boring and milling machines, CNC gantry machining centers, and CNC wire cutting.
I. Concept of numerical control technology and CNC machine tools
Numerical control technology is the use of digital program signals to control the machining process of machine tools through computers. As a machine for making machines, machine tools can make machine tools themselves and include various machining methods such as turning, milling, planing, grinding, boring, drilling, electric spark, shearing, bending, and laser cutting. The purpose of mechanical processing is to process metal blank parts into the required shapes, including two aspects: dimensional accuracy and geometric accuracy. Equipment that can perform the above functions is called a machine tool. A CNC machine tool is a high-precision and high-efficiency automated machine tool developed from a general machine tool. “Numerical control” means digital control. A CNC machine tool is an automated machine tool equipped with a program control system. This system can logically process programs specified by control codes or other symbolic instructions and decode them so that the machine tool can move and process parts. The control unit of a CNC machine tool is its core. The operation and monitoring of CNC machine tools are all completed in this numerical control unit. It is like the brain of a CNC machine tool. The numerical control equipment we usually refer to mainly includes CNC lathes and machining centers.
Numerical control technology is the use of digital program signals to control the machining process of machine tools through computers. As a machine for making machines, machine tools can make machine tools themselves and include various machining methods such as turning, milling, planing, grinding, boring, drilling, electric spark, shearing, bending, and laser cutting. The purpose of mechanical processing is to process metal blank parts into the required shapes, including two aspects: dimensional accuracy and geometric accuracy. Equipment that can perform the above functions is called a machine tool. A CNC machine tool is a high-precision and high-efficiency automated machine tool developed from a general machine tool. “Numerical control” means digital control. A CNC machine tool is an automated machine tool equipped with a program control system. This system can logically process programs specified by control codes or other symbolic instructions and decode them so that the machine tool can move and process parts. The control unit of a CNC machine tool is its core. The operation and monitoring of CNC machine tools are all completed in this numerical control unit. It is like the brain of a CNC machine tool. The numerical control equipment we usually refer to mainly includes CNC lathes and machining centers.
II. Differences between CNC machine tools and general machine tools
(1) Machining efficiency
Significantly improve productivity
CNC machine tools can significantly improve productivity. After the workpiece is clamped, input the pre-programmed machining program, and the machine tool will automatically complete the machining process. Once the machined part changes, generally only the numerical control program needs to be changed, greatly shortening the machining time. Compared with general machine tools, the productivity of CNC machine tools can be increased by several times or more. In the machining process of general machine tools, frequent manual operations and adjustments are often required, and the machining speed is relatively slow. While CNC machine tools can achieve continuous and automatic machining, reducing the pause and waiting time in the machining process, thus greatly improving production efficiency.
(2) Machining accuracy
Extremely high machining accuracy and stable product quality
CNC machine tools have high machining accuracy and very stable product quality. This is because CNC machine tools are machined automatically according to programs, and the machining accuracy can also be corrected and compensated by software. Almost all high-precision, sophisticated, and cutting-edge products in various enterprises are processed and manufactured using CNC machine tools. The machining accuracy of general machine tools is affected by multiple factors such as the operator’s technical level and the precision stability of the machine tool, making it difficult to ensure high-precision machining requirements. Through precise numerical control system control, CNC machine tools can achieve micrometer-level or even higher machining accuracy, ensuring that the dimensional accuracy and geometric accuracy of products meet strict requirements.
(3) Degree of automation
High degree of automation reduces labor intensity
The degree of automation of CNC machine tools is high, greatly reducing labor intensity and to a large extent blurring the difference between physical labor and mental labor. In the operation of general machine tools, operators need to perform a large number of manual operations such as adjusting tools, feed speeds, and controlling the machining process, resulting in high labor intensity. While for CNC machine tools, only the operator needs to input programs and perform necessary monitoring, and the machine tool can automatically complete the machining process. The work process of CNC machine tool operators has a high technological content, and has higher requirements for the quality of operators and higher technical requirements for maintenance personnel. People who can operate CNC machine tools are called “gray collars”; people who understand CNC machine tool maintenance are called “silver collars”; and people who can both operate and understand maintenance and are all-round talents in numerical control are called “gold collars”.
(1) Machining efficiency
Significantly improve productivity
CNC machine tools can significantly improve productivity. After the workpiece is clamped, input the pre-programmed machining program, and the machine tool will automatically complete the machining process. Once the machined part changes, generally only the numerical control program needs to be changed, greatly shortening the machining time. Compared with general machine tools, the productivity of CNC machine tools can be increased by several times or more. In the machining process of general machine tools, frequent manual operations and adjustments are often required, and the machining speed is relatively slow. While CNC machine tools can achieve continuous and automatic machining, reducing the pause and waiting time in the machining process, thus greatly improving production efficiency.
(2) Machining accuracy
Extremely high machining accuracy and stable product quality
CNC machine tools have high machining accuracy and very stable product quality. This is because CNC machine tools are machined automatically according to programs, and the machining accuracy can also be corrected and compensated by software. Almost all high-precision, sophisticated, and cutting-edge products in various enterprises are processed and manufactured using CNC machine tools. The machining accuracy of general machine tools is affected by multiple factors such as the operator’s technical level and the precision stability of the machine tool, making it difficult to ensure high-precision machining requirements. Through precise numerical control system control, CNC machine tools can achieve micrometer-level or even higher machining accuracy, ensuring that the dimensional accuracy and geometric accuracy of products meet strict requirements.
(3) Degree of automation
High degree of automation reduces labor intensity
The degree of automation of CNC machine tools is high, greatly reducing labor intensity and to a large extent blurring the difference between physical labor and mental labor. In the operation of general machine tools, operators need to perform a large number of manual operations such as adjusting tools, feed speeds, and controlling the machining process, resulting in high labor intensity. While for CNC machine tools, only the operator needs to input programs and perform necessary monitoring, and the machine tool can automatically complete the machining process. The work process of CNC machine tool operators has a high technological content, and has higher requirements for the quality of operators and higher technical requirements for maintenance personnel. People who can operate CNC machine tools are called “gray collars”; people who understand CNC machine tool maintenance are called “silver collars”; and people who can both operate and understand maintenance and are all-round talents in numerical control are called “gold collars”.
III. Advantages of CNC machine tools
(1) Adapt to multi-variety and small-batch production
With the diversification of market demand, multi-variety and small-batch production has become an important characteristic of modern manufacturing. CNC machine tools can quickly change the machining program of parts to adapt to the machining requirements of different parts without the need for complex machine tool adjustments and tooling changes. This gives CNC machine tools obvious advantages in multi-variety and small-batch production, which can greatly shorten the production cycle and reduce production costs.
(2) Strong processing ability for complex parts
For some parts with complex shapes and high precision requirements, CNC machine tools have strong processing capabilities. CNC machine tools can achieve high-precision processing of complex parts through technologies such as multi-axis linkage and complex tool path control. When general machine tools process complex parts, multiple processes and multiple clampings are often required, making the processing difficult and the accuracy difficult to guarantee.
(3) Improve product quality consistency
CNC machine tools have high machining accuracy and good stability, which can ensure product quality consistency. In batch production, CNC machine tools can ensure that the dimensional accuracy and geometric accuracy of each part are within a strict control range, avoiding product quality differences caused by human factors and unstable machine tool accuracy. This is of great significance for improving the market competitiveness of products.
(4) Facilitate the realization of production management informatization
CNC machine tools can be connected to computer networks to realize the informatization of production management. Through the communication interface of the numerical control system, information such as the running status and machining progress of the machine tool can be transmitted to the production management system in real time, facilitating production scheduling and quality monitoring by managers. At the same time, the management and transmission of numerical control programs can also be carried out through the network, improving production efficiency and management level.
(1) Adapt to multi-variety and small-batch production
With the diversification of market demand, multi-variety and small-batch production has become an important characteristic of modern manufacturing. CNC machine tools can quickly change the machining program of parts to adapt to the machining requirements of different parts without the need for complex machine tool adjustments and tooling changes. This gives CNC machine tools obvious advantages in multi-variety and small-batch production, which can greatly shorten the production cycle and reduce production costs.
(2) Strong processing ability for complex parts
For some parts with complex shapes and high precision requirements, CNC machine tools have strong processing capabilities. CNC machine tools can achieve high-precision processing of complex parts through technologies such as multi-axis linkage and complex tool path control. When general machine tools process complex parts, multiple processes and multiple clampings are often required, making the processing difficult and the accuracy difficult to guarantee.
(3) Improve product quality consistency
CNC machine tools have high machining accuracy and good stability, which can ensure product quality consistency. In batch production, CNC machine tools can ensure that the dimensional accuracy and geometric accuracy of each part are within a strict control range, avoiding product quality differences caused by human factors and unstable machine tool accuracy. This is of great significance for improving the market competitiveness of products.
(4) Facilitate the realization of production management informatization
CNC machine tools can be connected to computer networks to realize the informatization of production management. Through the communication interface of the numerical control system, information such as the running status and machining progress of the machine tool can be transmitted to the production management system in real time, facilitating production scheduling and quality monitoring by managers. At the same time, the management and transmission of numerical control programs can also be carried out through the network, improving production efficiency and management level.
IV. Conclusion
In summary, compared with general machine tools, CNC machine tools have significant advantages in terms of machining efficiency, machining accuracy, and degree of automation. The emergence and development of CNC machine tools have greatly promoted the progress of the mechanical processing industry and provided strong support for the development of modern manufacturing. With the continuous progress of technology, the performance of CNC machine tools will continue to improve, and the application range will also continue to expand. In the future manufacturing industry, CNC machine tools will continue to play an important role and become one of the key equipment for realizing intelligent manufacturing.
In summary, compared with general machine tools, CNC machine tools have significant advantages in terms of machining efficiency, machining accuracy, and degree of automation. The emergence and development of CNC machine tools have greatly promoted the progress of the mechanical processing industry and provided strong support for the development of modern manufacturing. With the continuous progress of technology, the performance of CNC machine tools will continue to improve, and the application range will also continue to expand. In the future manufacturing industry, CNC machine tools will continue to play an important role and become one of the key equipment for realizing intelligent manufacturing.