• Sawing: A type of cutting in which the cutting tool is a blade that has series of teeth, with each tooth removing a small amount of material. Sawing is typically used to shape raw material to the approximate size of the part, prior to additional processes.

• Tapping: An operation in which a tap enters the workpiece axially and cuts internal threads into an existing hole. The existing hole is typically drilled by the required tap drill size that will accommodate the desired tap. On a milling machine, the threads may be cut to a specified depth inside the hole (bottom tap) or the complete depth of a through hole (through tap).

• Broaching: Broaching involves use of a long multi-tooth cutting tool that makes successively deeper cuts. Broaching is used for machining internal and external surfaces such as key slots.

• Boring: An operation in which a boring tool enters the workpiece axially and cuts along an internal surface to form different features. The boring tool is a single-point cutting tool, which can be set to cut the desired diameter by using an adjustable boring head. Boring is commonly performed after drilling a hole in order to enlarge the diameter or obtain more precise dimensions. On a turning machine, a variety of features can be formed, including steps, tapers, chamfers, and contours.

• Turning: A turning operation in which a single-point tool moves axially, along the side of the workpiece, removing material to form different features, including steps, tapers, chamfers, and contours. Turning rotates the workpiece about its axis while applying cutting tools to create a desired shape.

• Drilling: Drilling produces holes in a workpiece using a fluted cutting tool. Hole-making is a class of machining operations that are specifically used to cut a hole into a workpiece. Machining, a material removal process, creates features on a part by cutting away the unwanted material and requires a machine, workpiece, fixture, and cutting tool. Hole-making can be performed on a variety of machines, including general machining equipment such as CNC milling machines or CNC turning machines.

• Milling: Milling is the most common form of machining, a material removal process, which can create a variety of features on a part by cutting away the unwanted material. The milling process requires a milling machine, workpiece, fixture, and cutter. The workpiece is a piece of pre-shaped material that is secured to the fixture, which itself is attached to a platform inside the milling machine. The cutter is a cutting tool with sharp teeth that is also secured in the milling machine and rotates at high speeds. By feeding the workpiece into the rotating cutter, material is cut away from this workpiece in the form of small chips to create the desired shape.

• Grinding: Grinding is a chip removal process in which the cutting tool is an abrasive grain wheel. Different types of grinding include Surface grinding, cylindrical grinding, internal grinding and center-less grinding.

• Sawing: A type of cutting in which the cutting tool is a blade that has series of teeth, with each tooth removing a small amount of material. Sawing is typically used to shape raw material to the approximate size of the part, prior to additional processes.

• Tapping: An operation in which a tap enters the workpiece axially and cuts internal threads into an existing hole. The existing hole is typically drilled by the required tap drill size that will accommodate the desired tap. On a milling machine, the threads may be cut to a specified depth inside the hole (bottom tap) or the complete depth of a through hole (through tap).

• Broaching: Broaching involves use of a long multi-tooth cutting tool that makes successively deeper cuts. Broaching is used for machining internal and external surfaces such as key slots.

• Boring: An operation in which a boring tool enters the workpiece axially and cuts along an internal surface to form different features. The boring tool is a single-point cutting tool, which can be set to cut the desired diameter by using an adjustable boring head. Boring is commonly performed after drilling a hole in order to enlarge the diameter or obtain more precise dimensions. On a turning machine, a variety of features can be formed, including steps, tapers, chamfers, and contours.

• Turning: A turning operation in which a single-point tool moves axially, along the side of the workpiece, removing material to form different features, including steps, tapers, chamfers, and contours. Turning rotates the workpiece about its axis while applying cutting tools to create a desired shape.

• Drilling: Drilling produces holes in a workpiece using a fluted cutting tool. Hole-making is a class of machining operations that are specifically used to cut a hole into a workpiece. Machining, a material removal process, creates features on a part by cutting away the unwanted material and requires a machine, workpiece, fixture, and cutting tool. Hole-making can be performed on a variety of machines, including general machining equipment such as CNC milling machines or CNC turning machines.

• Milling: Milling is the most common form of machining, a material removal process, which can create a variety of features on a part by cutting away the unwanted material. The milling process requires a milling machine, workpiece, fixture, and cutter. The workpiece is a piece of pre-shaped material that is secured to the fixture, which itself is attached to a platform inside the milling machine. The cutter is a cutting tool with sharp teeth that is also secured in the milling machine and rotates at high speeds. By feeding the workpiece into the rotating cutter, material is cut away from this workpiece in the form of small chips to create the desired shape.

• Grinding: Grinding is a chip removal process in which the cutting tool is an abrasive grain wheel. Different types of grinding include Surface grinding, cylindrical grinding, internal grinding and centerless grinding.

• Conventional Shearing: The metal cutting process in which flat surfaces cut using a scissors-like action; usually in straight line is known as conventional shearing.

• Turret Punching: Turret Punching creates shapes in sheet material by successively punching a series of basic shapes. Edges are cut by the shearing action of a punch and die.

• Blanking: During blanking, different shaped parts are created in sheet metal by applying a punch and die.

• Forging: The shaping of metal using localized compressive forces. Forging is often classified according to the temperature at which it is performed (i.e. cold, warm, or hot forging)

• Rolling: The process in which metal stock is passed through a set of roll to reduce the thickness is known as rolling. Rolling is classified according to the temperature of the metal rolled. If the temperature is above its recrystallization temperature then the process is known as hot rolling and if below then cold rolling.

• Extrusion: The process of creating objects of a fixed cross-sectional profile is known as Extrusion. A material is pushed or drawn through a die of the desired cross-section.

• Drawing: The process of forming sheet metal into shapes or stretched over a form is known as drawing. Deep drawing is a type of drawing where the depth of the part can be greater than its diameter. Deep drawing is generally done in multiple steps called draw reductions.

• Bending: The process of producing V-shape, U-shape, or channel shape along a straight axis in ductile material, most commonly Metal is known as bending. During bending, the workpiece is bent to form flanges, contours, curls, seams, corrugations and other geometries by means of applying force through hydraulic, pneumatic and electrical machines.

• Spinning: The process in which a disc or tube of metal is rotated at high speed and formed into an axially symmetric part is known as spinning. Spinning can be performed by CNC lathe.

Fabrication includes several processes of manufacturing metal components by changing the raw material using various tools. Metal fabrication processes can be classified as cold, warm, and hot working depending on the temperature at which the material is processed. The factors influencing the metal fabrication process included the type of material being machined, the rate of production, the desired geometry and other physical requirements of the part. The emergence of CNC (Computer numerical control) technology brought automation and greater accuracy to these techniques.

Metal fabrication can be divided into the following categories:

1) Metal Forming: Any manufacturing process by which parts of components are fabricated by shaping or molding a piece of metal is known as metal forming.

2) Shearing: The process in which machines equipped to perform shearing action on metals cuts can create strips and free-form shapes for use in the manufacturing process, or shearing action can make holes within metal sheet to create ventilation covers or other specialized equipment from one metal sheet instead of distinct parts.

3) Material Removal: The process in which a cutting tool removes unwanted material from a workpiece to produce the desired shape. The workpiece is typically cut from the larger piece of stock, which is available in a variety of standard shapes.

4) Advanced Methods: There are some of the advance methods which are used for metal fabrication. They are

a) Laser Cutting: Laser cutting involves focusing a beam of high density energy on the surface of the workpiece. The beam evaporates portions of the workpiece in a controlled manner.

b) Electro Discharge Machining: Electro discharge machining is based on erosion of metal by spark discharges. This process can be used for machining any material which is an electrical conductor.

c) Wire EDM: The wire EDM or Electro Discharge Machining produces part shapes by cutting a metal work piece with a continuously moving wire by means of rapid, repetitive spark discharges. This process is used to cut thin and thick metal and is often used to make punches, tools and dies from hard metals.

d) Waterjet Cutting: In this process, the force of a water jet is used to cut material. The water jet acts like a saw and cuts narrow kerfs in the workpiece. Most of metals, plastics, fabrics, wood products, rubber, insulating material, leather, brick and composite materials can be cut using the waterjet process.