CNC Machining is a generic term used for various machining applications. "CNC" stands for Computer Numerical Control and refers to the programmable functions of a machine that allow the machine to perform many functions with minimal human control. CNC machining is the manufacture of parts using CNC-controlled machines. The term describes a range of subtractive manufacturing processes that remove material from bar stock or blanks to produce finished parts. There are 5 different types of CNC equipment to perform 5 common types of CNC Precision Machining.
CNC precision machining is widely used in medical, aerospace, industrial, oil and gas, hydraulic, and other industries. A wide range of materials can be CNC machined and can machine metal, plastic, glass, composites and wood.
Precision Cnc Machining offers many advantages over machining without CNC programmable capabilities. Significantly reduced cycle times, improved surface smoothness, and improved quality and consistency.
The 5 most common Precision CNC Machining methods are described below:
1 – CNC Lathe Machining
CNC lathes feature the ability to rotate (turn) material during machining operations. The cutting tool of a lathe is fed in a linear motion along the rotating bar; this removes material around the circumference until the desired diameter and features are achieved.
A subset of CNC lathes are CNC Swiss lathes (also called automatic lathes). With a CNC Swiss lathe, the bar is rotated and slid axially through a guide bush into an automatic lathe, and the cut parts are then machined automatically. Generally speaking, CNC automatic lathes are suitable for machining small diameter parts.
CNC lathe machining can create internal and external features on parts: including drilling, broaching, reaming, grooving, tapping, threading. Components manufactured by CNC lathes and turning centers include screws, bolts, shafts, joints, and more.
2 – CNC Milling
CNC milling machines feature the ability to rotate the cutting tool while keeping the workpiece/block of material stationary. They can produce a variety of shapes, including face milling (shallow, flat surfaces and cavities in workpieces) and perimeter milling (deep cavities such as slots and threads).
Parts suitable for production on CNC milling machines are usually square or rectangular shapes with various features.
3 – CNC Laser Machining
CNC laser machines have a pointed router with a highly focused laser beam for precisely cutting, slicing or engraving materials. The laser heats the material and melts or vaporizes it, creating cuts in the material. Typically, the material is in sheet form. The laser beam moves back and forth across the material to create precise cuts.
Compared to conventional cutting equipment (lathes, turning centers, milling machines), this process allows for wider design freedom and often produces cuts and/or edges that do not require additional finishing processes.
CNC laser engravers are often used for marking (and decorating) machined parts. For example, logos and company names are difficult to machine with CNC turning or CNC milling. However, it is very easy to engrave with a CNC laser, and even after the machining operation is complete, it can be added to a component using laser engraving.
4 – CNC Electrical Discharge Machining (EDM)
CNC Electrical Discharge Machining (EDM) uses a highly controlled electrical discharge to machine material into the desired shape. It can also be called spark corrosion, spark machining, or wire burning.
A component is placed under the electrode wire, and the machine is programmed to emit an electrical discharge from the wire, producing intense heat (up to 11,700°C). The material is melted or washed away by the liquid to create the desired shape or feature.
EDM is most commonly used to create precise micro-holes, grooves, tapered or angled features, and a variety of other more complex features in parts or workpieces. It is often used for difficult shapes and sizes, and is often used for very hard metals. such as gears.
5 – CNC Plasma Cutter
CNC plasma cutters are also used to cut materials. However, they did this using a high-power plasma (electron-ionized gas) torch controlled by a computer. Similar in function to hand-held pneumatic torches for welding (up to 5500 degrees Celsius), plasma torches can reach up to 27500 degrees Celsius. The plasma torch melts through the workpiece to create cuts in the material.
Whenever CNC plasma cutting is used, the material being cut must be conductive. Typical materials are conductive metals such as steel, stainless steel, aluminum, brass and copper.
Precision CNC machining offers a wide range of production capabilities for manufacturing components and finishing. Depending on the usage environment, required materials, lead times, quantities, budget, and required features, there is usually an optimal method that will provide the desired results.
More information
At Ningbo Tianhui Machinery Co., Ltd., the types of machines we use are CNC lathes and CNC machining centers. Our machines can perform some milling operations and cutting operations. We can process a variety of metals and thermoplastics to produce the parts our customers need.
If you need CNC precision machining services, please feel free to contact us. Our team is happy to review your drawings and provide feedback and comments on features in your designs.
