A manufacturing process in which an item is made from raw or semi finished materials instead of being assembled from ready- made components or parts is called Fabrication. It is used to manufacture steelwork components that will, when assembled and join, form a complete frame. The Different machines and structures are constructed through fabrication. Fabrication has a great scope in the industrial world.
There are different kinds of Fabrication. Such as:
Cutting is a process in which the different structures are cut to the required length and the different plates are profiled to desired size and shape.
Where curved steel work is required, the steel will be sent to a specialist Fabricator. Here curves and bendings are created by the use of roller bending or press breaking equipment. This process is called bending.
Welding is a core activity in the fabrication factory, undertaken by skilled, qualified operatives working to a welding quality management system under the control of a Responsible Welding Coordinator. It is used to prepare joints for connection in the shop and on site, and for the attachment of other fixtures and fittings. Different welding techniques are used for different activities within the fabrication factory.
Essentially, the welding process uses an electric arc to generate heat to melt the parent material in the joint. A separate filler material supplied as a consumable electrode also melts and combines with the parent material to form a molten weld pool. As welding progresses along the joint, the weld pool solidifies fusing the parent and weld metal together. Several passes or runs may be required to fill the joint or to build up the weld to the design size.
Machining is the process of removing unwanted material from the block of metal to get the desired shape. Machining is a trade, in and of itself, although Fab shops will generally entail a limited machining capability including; metal lathes, mills, magnetic based drills, along with other portable metal working tools.
Forming is a process of material deformation. Forming is typically applied to metals. To define the process, a raw material piece is formed by applying force to an object. The force must be great enough to change the shape of the object from its initial shape. The process of forming can be controlled with the use of tools such as punches or dies.
Shearing is the process of making a long cut on a piece of metal. It is, in effect, just like the action of one of those paper cutters with the long chop-handle. This is done on sheet metal.
Stamping is very similar to punching, except the material is not cut. The die is shaped to make a raised portion of material rather than penetrating.
There are many other types of fabrication processes that are less common than the ones in the list above. There are also constantly new types of fabrication methods being developed with the passage of time.