What are the differences between CNC turning processing and CNC milling processing?

CNC turning (numerical control turning) and CNC milling (numerical control milling) are two common types of numerical control processing methods. They have significant differences in processing principles, workpiece movement methods, processing objects, and tool types, among other aspects. The following is a detailed explanation comparing the two from multiple dimensions:

1.Processing principle

CNC machining:

Working principle: The workpiece rotates while the cutting tool cuts the material of the workpiece along the designated path.

Main movements: The workpiece rotates around its axis (primary motion), and the tool moves in a straight line (secondary motion).

CNC milling processing:

Working principle: The cutting tool rotates, and the workpiece moves relative to the tool through the movement of the worktable for the cutting process.

Main movements: Rotation of the cutting tool (primary movement), movement of the workpiece or the cutting tool along the X, Y, and Z axes (feed movement).

2. Processing Object

CNC turning processing:

Typical application: Primarily used for processing rotational body parts, such as shafts, discs, and sleeve-type parts.

Shape characteristics: Suitable for processing cylindrical surfaces, inner holes, conical surfaces, spherical surfaces, threads, and other rotational symmetrical parts.

CNC milling processing:

Typical application: Suitable for processing planes, grooves, holes, complex curved surfaces, contours, etc.

Shape characteristics: Widely used in the processing of complex geometric shapes, such as molds, complex curved surfaces and grooves on parts, etc.

3. Tool Type

CNC turning processing:

Common cutting tools: The main tools used are turning tools, including external cylindrical turning tools, internal hole turning tools, slotting tools, and thread turning tools, etc.

Tool fixation method: The tool is generally fixed on the tool holder. The tool holder can be replaced or an automatic tool changing device can be used.

CNC milling processing:

Common tools: Utilize a variety of milling cutters, such as end mills, face mills, ball nose mills, and angle mills, etc.

Tool fixation method: The tool is fixed on the spindle. Usually, it is clamped using a tool holder and can be automatically changed through the tool magazine.

4. Processing accuracy and surface quality

CNC turning processing:

Accuracy: Suitable for the processing of high-precision rotating body parts, and it can usually achieve very high dimensional accuracy.

Surface quality: By optimizing the cutting parameters, excellent surface roughness can be achieved.

CNC milling processing:

Accuracy: Suitable for precise processing of complex-shaped parts, especially performing exceptionally well in three-dimensional curved surface machining.

Surface quality: By appropriately selecting milling parameters and tools, high-quality surface effects can be achieved. However, in extremely detailed surface treatments, it may be slightly inferior to turning.

5. Processing Efficiency

CNC turning processing:

Efficiency: For rotating body parts, the machining efficiency of turning is relatively high. Especially for long shaft parts, the advantages of turning are particularly prominent.

Production cycle: Suitable for mass production of rotary body parts. The time for tool change and machine adjustment is relatively short.

CNC milling processing:

Efficiency: Suitable for processing various geometric shapes, especially for complex parts that require multiple tool changes and multiple processing steps.

Production cycle: For complex parts, milling may require longer setup and programming time, but multi-axis coordinated milling can enhance processing efficiency.

6. Equipment Structure

CNC Lathe:

Main components: These include the bed, spindle box, tool holder, tailstock (or center rest), and the numerical control system, etc.

Design feature: Emphasizes the rotational movement of the workpiece and the linear feed movement of the cutting tool.

CNC Milling Machine:

Main components: These include the bed, spindle, worktable, tool magazine, and CNC system, etc.

Design feature: Emphasizes the rotation of the cutting tool and the multi-axis coordinated movement of the worktable (or the cutting tool).

7. Application Scope

CNC turning processing:

Application industries: Widely used in the processing of shaft and disc parts in industries such as automobiles, aerospace, and mechanical manufacturing.

Typical components: engine shaft, wheels, flanges, shaft sleeves, etc.

CNC milling processing:

Application industries: Applied to industries such as mold manufacturing, processing of complex parts, medical devices, aerospace, etc.

Typical parts: mold cavities, complex curved surface parts, electronic product casings, medical equipment parts, etc.

In summary, CNC turning and CNC milling each have their own unique advantages and applicable scopes. The choice of which processing method to use depends on the shape, size, precision requirements of the specific part, as well as the production batch. The two methods are often used together to meet the comprehensive processing needs of complex parts.