CNC stands for "Computer Numerical Control" or "Computerized Numerical Control," referring to the use of computers to control machine tools. By automating machine tool movements (direction, speed, amount of material to be processed, etc.) through programming, CNC enables the efficient and safe production of high-quality products.
In the past, equipment like milling machines and lathes were manually operated by workers. However, this method faced challenges such as:
- Variability in product quality due to differences in operator skills.
- Difficulty in machining complex shapes.
- Limitations in improving work efficiency.
The introduction of automated machine movements via digital control addressed these issues. Today, many machine tools incorporate CNC technology. Moreover, combining CNC machines with CAD (Computer-Aided Design) and CAM (Computer-Aided Manufacturing) systems enables seamless integration of design and machining within a computer.
Applications of CNC Machines
CNC machines are widely used across industries for manufacturing components in automobiles, medical devices, airplanes, molds, and more. They excel in precision machining tasks that are difficult to achieve with manual (non-NC) machine tools, such as freeform surface machining or complex 3D shapes. Additionally, some CNC machines can process non-metal materials, such as plastics and wood, expanding their versatility.
Difference Between CNC and NC
A similar term to CNC is NC, which stands for "Numerical Control." The key distinction lies in the absence of "Computer" in NC.
NC refers to a method of controlling machine tools using only hardware, such as transistors or arithmetic circuits, without involving a computer. Developed in the 1950s, NC technology relied on combinations of multiple boards, such as data reading, calculation, and servo control boards, to function.
In contrast, CNC replaces NC's hardware-based control mechanisms with computer-based (microcomputer) control, using specialized programming languages to manage operations such as tool speed, type, and path through software.
In recent years, many NC systems have been equipped with computers, blurring the distinction between NC and CNC.
How to Use CNC Machines
When processing materials with CNC, the workflow generally involves the following steps:
- Create 3D data: Use 3D CAD software to design the product.
- Generate NC program data: Use CAM software to create the NC program based on the 3D CAD data.
- Prepare tools: Set up the necessary cutting tools and secure them in the tool holder.
- Install materials: Mount the material on the machining table.
- Start machining: Begin the CNC machining process.
CAD is a tool for creating 3D design data, while CAM generates the NC program based on the CAD data. The NC program controls aspects such as tool speed, type, replacement timing, and tool paths in the form of code. CAM software can automatically create NC programs by inputting tool and machining conditions, making CNC machining accessible even to users without programming expertise.
