Machining

General Knowledge

Machining is a material removal process used in manufacturing, where high precision and tight tolerance parts are required.
The key operations involved in machining include turning, milling, drilling, and grinding.
Traditional machining involves the manual operation of tools, but CNC (Computer Numerical Control) machining has increased automation and precision significantly.

Turning is a machining process where the workpiece rotates against a cutting tool, which moved in a linear motion.
It is especially used to create cylindrical parts and features such as holes.
Examples of turned products include screws, metal spindles, and motor shafts.

Milling is a machining process which involves rotating multi-toothed cutter and lateral movement of the workpiece in relation to the cutter.
This process can create a variety of features including slots, pockets, and complex contoured surfaces.
Milling can be done manually, but it is mainly performed on CNC machines for precision.

Drilling is a machining operation that produces cylindrical holes in a workpiece. It is carried out by a rotating tool, the drill.
Variations of drilling includes counterboring, countersinking, and reaming.
Automated processes, like CNC drilling, create holes rapidly and to high levels of precision.

Grinding is a finishing operation that uses a rotating abrasive wheel to smooth or flatten the surface of metallic or nonmetallic materials.
This process can achieve high accuracy and surface finish, but it results in high temperatures and requires coolants.
Common grind processes include surface grinding, cylindrical grinding, and creep feed grinding.

The shape complexity of the product heavily influences the chosen machining process. Parts with intricate detailing often require techniques such as milling.
Material type is a critical setter. Certain materials are better suited to specific processes.
Volume of production: Turning and milling are suitable for small to medium production size, whereas drilling and grinding are typically used for high volume production.
The ultimate quality and finish of the product will dictate the best machining process. For high precision requirements, processes like grinding may be preferable.
The available machinery can also determine the process used. For instance, companies with CNC milling machine are likely to use milling process for manufacturing.