What is CNC Machining? | Definition, Processes, Components & More What is CNC Machining?
CNC 101: The term CNC stands for 'computer numerical control', and the CNC Vertical Machining Center
definition is that it is a subtractive manufacturing process that typically employs computerized controls and machine tools to remove layers of material from a stock piece—known as the blank or workpiece—and produces a custom-designed part. This process is suitable for a wide range of materials, including metals, plastics, wood, glass, foam, and composites, and finds application in a variety of industries, such as large CNC machining, machining of parts and prototypes for telecommunications, and CNC machining aerospace parts, which require tighter tolerances than other industries. Note there is a difference between the CNC machining definition and the CNC machine definition- one is a process and the other is a machine. A CNC Lathe
(sometimes incorrectly referred to as a C and C machine) is a programmable machine that is capable of autonomously performing the operations of CNC machining.
Subtractive manufacturing processes, such as CNC machining, are often presented in contrast to additive manufacturing processes, such as 3D printing, or formative manufacturing processes, such as liquid injection molding. While subtractive processes remove layers of material from the workpiece to produce custom shapes and designs, additive processes assemble layers of material to produce the desired form and formative processes deform and displace stock material into the desired shape. The automated nature of CNC machining enables the production of high precision and high accuracy, simple parts and cost-effectiveness when fulfilling one-off and medium-volume production runs. However, while CNC machining demonstrates certain advantages over other manufacturing processes, the degree of complexity and intricacy attainable for part design and the cost-effectiveness of producing complex parts is limited. Overview of CNC Machining Process
Evolving from the numerical control (NC) machining process which utilized punched tape cards, CNC machining is a manufacturing process which utilizes computerized controls to operate and manipulate machine and cutting tools to shape stock material—e.g., metal, plastic, wood, foam, composite, etc.—into custom parts and designs. While theCNC Compound Machining Center
process offers various capabilities and operations, the fundamental principles of the process remain largely the same throughout all of them. The basic CNC machining process includes the following stages:
Designing the CAD model
Converting the CAD file to a CNC program
Preparing the CNC machine
Executing the machining operation Types of CNC Machining Operations CNC Engraving Machine
is a manufacturing process suitable for a wide variety of industries, including automotive, aerospace, construction, and agriculture, and able to produce a range of products, such as automobile frames, surgical equipment, airplane engines, gears, and hand and garden tools. The process encompasses several different computer-controlled machining operations—including mechanical, chemical, electrical, and thermal processes—which remove the necessary material from the workpiece to produce a custom-designed part or product. What is a CNC Machine? Types of CNC Machines and Machine Tools
Depending on the machining operation being performed, the CNC Tapping Center
process employs a variety of CNC machines and machine tools to produce the custom-designed part or product. While the equipment may vary in other ways from operation to operation and application to application, the integration of computer numerical control components and software (as outlined above) remains consistent across all CNC machining equipment and processes. The Laser Cutting Machine and Process
Laser cutting is a non-contact, thermal-based fabrication process suitable for metal and non-metal materials. For the laser cutting process to run smoothly and at optimum capacity, several factors should be taken into consideration, such as the laser cutting machine’s configuration and settings, the material being cut and its properties, and the type of laser and assist gas employed. Overview of Laser Machine Components and Mechanics
In contrast to mechanical cutting, which utilizes cutting tools and power-driven equipment, and waterjet cutting, which utilizes pressurized water and abrasive material, laser cutting employs a Laser Machine
to produce cuts, engravings, and markings. While laser cutting machines vary from model to model and application to application, the typical setup includes a laser resonator assembly, mirrors, and a laser cutting head which contains a laser focusing lens, a pressurized gas assembly, and a nozzle. What is a Hydraulic Press?
A Hydraulic Press
is a mechanical device that uses the static pressure of a liquid, as defined by Pascal‘s principle, to shape, deform, and configure various types of metals, plastics, rubber, and wood. The mechanism of a hydraulic press consists of a mainframe, power system, and controls.
Pascal‘s principle states that when pressure is applied to a confined liquid, a pressure change occurs in the liquid. For a hydraulic press, the pressure in a liquid is applied by a piston that works like a pump to create mechanical force. How a Hydraulic Press Works
The process of a hydraulic press begins when a hydraulic fluid is forced into a double acting piston. The compressive force inside the small hydraulic cylinder pushes the fluid into a larger cylinder where more force and pressure are applied. The movement of the larger piston forces the fluid back into the smaller piston cylinder.
The passage of the fluids between the two pistons creates increased pressure that produces mechanical force to drive the anvil on a hydraulic press downward onto a workpiece that is deformed to produce a desired shape. Once the movement is complete, the pressure is released and the anvil returns to its original position.