CNC vs. Traditional Machine Tools: Understanding the Differences and Making the Right Choice
With benefits such as: Ensuring high accuracy, quality, uniform design, can process even complex parts,… Therefore, CNC machine tools are increasingly widely used in the precision mechanical industry or in sheet metal processing units, mold processing, machine parts,… It is also thanks to the use of machine tools applying modern CNC technology that has helped the industry in our country have many important developments. However, at present, there are still many individuals and units who still do not understand this technology or how to distinguish it from traditional machine tools, thereby not knowing how to apply it to the company’s production process in the most effective way. Let’s refer to the article “Comparison of CNC machine tools and traditional machine tools” with RX Tradex to clearly distinguish these 2 types of machines!
1. Overview of machine tools and CNC machine tools.
1.1. What is a machine tool?
Machine tools are devices and machines commonly used in the mechanical industry, capable of changing the shape, size and accuracy of machine parts and parts. Popular types of machine tools today such as: Lathes, gear milling machines, drills, boring machines, milling machines, cutting machines, planers … Traditional machine tools are often used to process metal or other solid materials such as wood, glass,…
1.2. What is CNC Machine Tool?
CNC machine tools (CNC machines) are machines that are controlled automatically with the help of computers. The term CNC stands for “Computer Numerical Control”, which can simply be understood as “computer control”. Including numerical control equipment (referred to as CNC for short). CNC machines are capable of performing various machining processes such as: CNC laser cutting, peeling, milling, turning,… These processing processes are often performed to shape machine parts to the desired shape on many different materials such as iron, steel, copper, aluminum,…
For CNC machine tools, the design drawings are pre-programmed, enterprises only need to install the sample on their computer screen and then select the appropriate mode to conduct production processing. Immediately, the computer will send signals to the machine system to create products with high accuracy without spending time and labor like traditional machines before.
2. Differences between CNC machine tools and traditional machine tools
2.1. Advantages and limitations of traditional machine tools compared to CNC machine tools:
| Traditional machine tools | CNC Machine Tools | |
| Advantage: | + Cost savings if production is small.+ Effective use for simple metal shapes. | + Flexibility and consistency.+ Shorten production time. Save labor costs.+ Uniform and safe design.+ High machining accuracy thanks to high machine precision cable (measurement accuracy 1/1000 mm).+ The machine can process many sides of products.+ Low machining time thanks to production organization and better combination of dispersed work steps.+ High machine utilization factor thanks to automatic and repeatable machine operation.+ Reduce waste. |
| Disadvantage | + Slow production speed.+ Not meeting large-scale production needs.+ Low accuracy due to human dependence.+ High waste. | + Costly because of high initial investment.+ Need highly qualified technical staff to program or operate the machine.+ If the machine fails, it takes a long time to repair. |
2.2. Similarities of CNC machine tools and traditional machine tools.
CNC machine tools and traditional machine tools have similarities in basic structure, including: Machine tables, cutters, jigs, spindles,… They are all called mother machines, which are one of the important machines for producing parts of other machines. Besides, CNC machine tools and traditional machine tools also have many differences, mainly in the machine control system.
2.3. The differences between CNC machine tools and traditional machine tools.
Differences in data entry:
Conventional machine tools:
Workers adjust the machine by hand based on production tasks and drawings. Besides, traditional machine tools often use workpiece jigs and cutting tools for adjustment.
CNC Machine Tools:
Programs can be entered into CNC control systems via keyboard, CD or communication port. Many programs are stored in internal memory, and additional memory is used in modern control systems. Engineers or specialists will make adjustments directly at the control panel on the machine or indirectly through software on the computer.
Different in machine control:
Traditional machine tools:
· Engineers have to manually adjust the machinery according to the drawings. Then jig the workpieces, tools and control them. It’s all manual.
· The operator must measure and check the size of the workpiece himself. to ensure its accuracy. If many parts are manufactured, the process must be repeated several times.
CNC Machine Tools:
· Thanks to the built-in measuring sensors, one can check the dimensions during processing. At the same time, the work can be easily performed on the machining process control system.
· The internal memory of the machine will store programs, machine parameters, knife size, calibration values,… Additional error forecasting software can be integrated.
· The size of the workpiece can be automatically measured by the machine’s built-in sensor.
Differs in the drive of the machine:
Traditional machine tools:
· Main drive:
+ Requires a large speed adjustment range with constant power.
+ Small eccentricity.
+ Ability to position angles.
· Driven drive: A servo motor or an inverter motor.
+ Create the border of the product through the movement of the axes.
+ Most are 3-phase synchronous motors with brushless permanent magnets.
+ The rotational speed is controlled by changing the frequency and voltage.
CNC Machine Tools:
· Main drive:
+ 1-way current motor: Stepless speed adjustment by excitation current.
+ AC current motor: Stepless speed adjustment by frequency converter. When changing the applied force, the number of revolutions remains constant.
· Tooling drive: 1-way and alternating current motors with ball nut vitmes for each independent tooling shaft X, Y, Z (depending on the type of CNC machine with corresponding axes such as: 2-axis, 3-axis, 4-axis, 5-axis ,…).
Different in machining benefits on machines:
Traditional machine tools:
· The range of operation is wide and capable of performing a variety of operations.
· The machine can handle a wide range of products. The machine handling size can be adjusted within a certain range with relative accuracy.
· The machine is applied in many industries such as machine building and other engineering disciplines that do not require high precision.
CNC Machine Tools:
· High automation ability: The machine can automatically perform many different operations at the same time. Manipulations such as: Replacing tools, fixing tool errors, checking part sizes, removing workpieces from the cutting area.
· Most CNC machines can perform a variety of operations without changing the position of the part.
· The machine can be processed on many materials such as iron, copper, aluminum, steel, stainless steel and other materials,…
· The machine meets the details that need high precision and applications in many different fields such as: Aerospace, machinery manufacturing, auto parts, medical equipment,…
3. Summarize.
From the above analysis, it can be seen that the application of CNC numerical control technology is very necessary. Compared with traditional machine tools, CNC machine tools have many outstanding advantages. Thanks to technological improvements, machine tools are increasingly evolving from ensuring product accuracy to automating the production process. Shorten processing time and save costs for businesses.
And for a better understanding of the use and functionality of CNC machine tools and machine tools, as well as the opportunity to learn and experience industry-leading technologies, join industry-leading international exhibitions such as the Metalex Expo organized by RX Tradex. In addition, the event also featured many trends and new metal cutting technologies towards mechanical automation. In addition, businesses can refer to other events organized by RX Tradex in 2023 such as Vietnam Manufacturing Expo, Waste and Recycling Vietnam and NEPCON Vietnam to increase learning opportunities and expand trade connections.
