What Types of Parts are Commonly Used for CNC Machining?

1. Depending on the part material, what materials can CNC process?

Almost all machining materials can be used on CNC machines. It really depends on the application. Common materials include metals such as aluminum, brass, copper, steel and titanium, as well as wood, foam, fiberglass and plastics such as polypropylene, ABS, POM, PC, nylon, etc. But some materials are too soft or too soft and rigid to be machined on CNC machines. For example, materials like rubber or silicone are too soft to CNC, and ceramics are too hard to precision machine.

2. According to the structure and shape of the parts, it can be divided into:

CNC machining occupies a very high position in CNC equipment. Many parts processing companies use CNC machining centers. So what types of parts can be processed by CNC machining? As we all know, CNC machining centers are suitable for processing parts that are complex, have many processes, have high requirements, require multiple types of ordinary machine tools and multiple tool fixtures, and require multiple clamping adjustments before they can be processed. Its processing objects are mainly box parts, complex curved surfaces, special-shaped parts, plate-clad parts and special processing.

(1) Box parts.

Box parts generally refer to parts with multiple hole systems, cavities inside, and a certain proportion of length, width, and height. Such parts are mostly used in machine tools, automobiles, aircraft manufacturing and other industries. Box-shaped parts generally require multi-station hole making and surface processing, and the tolerance requirements are relatively strict, especially the geometric tolerance requirements are relatively strict. They usually need to go through milling, drilling, expanding, boring, reaming, countersinking, tapping and other processes, which require More knives. For machining centers that process box parts, when there are many processing stations and the parts require multiple rotations of the worktable to complete, a horizontal boring and milling machining center is generally selected.

(2) Complex surfaces.

Complex curved surfaces occupy a particularly important position in the machinery manufacturing industry, especially in the aerospace industry. It is difficult or even impossible to complete complex curved surfaces using ordinary machining methods. In our country, the traditional method is to use precision casting, which can be imagined to have low precision. Complex curved surface parts, such as: various impellers, guide wheels, spheres, various curved surface forming molds, propellers and underwater vehicle propellers, and some other free-form surfaces. The following are more typical:

(3) Special-shaped parts.

Special-shaped parts are parts with irregular shapes, and most of them require multi-station mixed processing of points, lines, and surfaces. The rigidity of special-shaped parts is generally poor, the clamping deformation is difficult to control, and the processing accuracy is difficult to guarantee. Even some parts of some parts are difficult to complete with ordinary machine tools. When processing with a machining center, reasonable process measures should be taken, one or two clampings, and the characteristics of the machining center’s multi-station point, line, and surface mixed processing to complete multiple processes or all processes.

(4) Disks, sleeves and plates.

The end face has keyways, or radial holes, or distributed hole systems, crank sleeves or shaft parts, such as flange sleeves, keyways or square-head shaft parts, etc., as well as porous processed plates, such as various motor end faces with distribution Vertical machining centers should be selected for disc parts with holes and curved surfaces, while horizontal machining centers with radial holes should be selected.

(5) New product trial parts

The machining center has wide adaptability and high flexibility. When changing the processing object, you only need to compile and input the new program to realize processing.

3. According to the precision of parts and application industry, it can be divided into:

CNC precision machining can produce a variety of parts with high precision requirements, including but not limited to the following:

High-precision mechanical parts: These parts usually require high-precision cutting, drilling, milling and other processing operations to achieve high-precision fit and surface finish requirements.

Mold parts: including the punch, concave mold, core, cavity and other parts of the mold. These parts usually require high-precision processing and grinding to ensure the dimensional accuracy and surface finish of the mold.

Optical parts: including optical lenses, prisms, reflectors and other parts. These parts usually require high-precision grinding and polishing to ensure optical performance and surface quality.

Aerospace parts: The aerospace field has very high requirements for the accuracy and strength of parts. CNC precision machining can produce a variety of high-strength, high-precision aerospace parts, such as engine turbine blades, shafts, gears, etc.

Medical device parts: The field of medical devices has very high requirements on the accuracy and surface quality of parts. CNC precision machining can produce various medical device parts, such as surgical instruments, implants, etc.

Precision instrument parts: Precision instruments have very high requirements on the accuracy and stability of parts. CNC precision machining can produce various precision instrument parts, such as sensors, controllers, etc.

Microelectronic parts: The field of microelectronics has very high requirements on the size and accuracy of parts. CNC precision machining can produce various microelectronic parts, such as chips, lead frames, etc.

In short, CNC precision machining can produce a variety of parts with high precision and high quality requirements, and is widely used in machinery manufacturing, aerospace, medical equipment, precision instruments, microelectronics and other fields.

4. According to the common uses of parts, they can be divided into:

CNC precision parts processing products that can be turned “

In the CNC machining industry, CNC lathes are used to process straight cylinders, inclined cylinders, arcs, and various threads, grooves, and worms. They can also process some complex rotating surfaces, such as hyperboloids, etc. Typical CNC turned parts include shift knobs, knobs, pulleys, shafts, hubs, bushings, flywheels, etc.

CNC precision parts processing products that can be milled”

CNC milling machines are mainly used to process various complex plane, curved surface and shell parts. For example, various cams, molds, connecting rods, blades, propellers, boxes, and shell-shaped parts are all processed by CNC milling. In summary, typical CNC milled parts can be divided into three categories: flat parts, surface parts, and angle parts.

Each machine has its own accuracy level and processing sequence. Sometimes, some processing equipment will be used to manufacture certain components.

5. What can’t CNC machining do?

Almost any part can be made on a CNC machine, but there are some limitations. Parts with certain features are not suitable for CNC machining, including:

1. Internal vertical angle

Since the CNC milling tool has a cylindrical shape, it will leave a radius at the vertical corner when cutting the inner wall. While it is possible to reduce the nose radius by using a smaller diameter tool, internal vertical corners cannot be made no matter how small the diameter of the tool used.

2. Precision parts with deep cavities

Due to the limited cutting length, tools often work best when the cutting depth reaches a mold cavity 2-3 times its diameter. A milling cavity whose depth exceeds 4 times the tool diameter will greatly increase processing difficulty and tool breakage.

3. Thin-walled precision parts

Thin walls are difficult to machine and can easily deform or break during CNC machining. Thin-wall machining requires multiple passes at low depths of cut, and thin features are also prone to vibration, making it challenging to machine them accurately and adding to machining time.

4. Precision parts with cutouts

Some of the cuts on the inner walls of the part are difficult to CNC because the cutting tool cannot get there to do any machining.

Therefore, it is recommended to avoid using these features before designing for CNC precision part machining.

CNC machining provides precise cutting and manipulation capabilities and it is easy to say that almost any product made of wood, metal, aluminum, alloys and various other materials can be completely constructed or improved by using CNC machine tools. CNC has its limitations, so before designing a CNC to machine precision parts, it is recommended to avoid shortcuts.