About Metal Fabrication
Metal fabrication is a process in which metal is cut, shaped, and assembled into a finished product. The various stages of metal fabrication may be manual or mechanized. To start fabricating, a design is created that conceptualizes the build using either 3D or 2D design, then construction begins.
After a design has been created, the next step in metal fabrication depends on what the part being created requires. One or more of the following steps may be implemented to create the finished unit.
- Cutting – Usually the first step in metal fabrication, raw material like sheet metal, wires, rods, or bars, are cut to size by sawing, shearing, or torching. When a job requires precision, cutting will be done using either lasers, plasma beams, or waterjet to create exact cuts quickly and efficiently.
- Forming or Folding – force is applied to the metal material to alter its shape to the specified 3D design. The metal is bent by hammer or press brakes. These manufacturing processes include cold and hot heading.
- Casting – liquified metal is poured into a mold and with enough time or the proper chemical mixing, the metal becomes solid in the shape of the mold. Casting is used for more complex pieces and creates a more homogeneous microstructure.
- Deep drawing – a metal blank is stretched into a new shape and length with compression forces being applied. The metal can be a sheet, bar, or wire and is usually done at room temperature.
- Forging – metal is formed using compression forces like hammers, presses and rolls. Forging can be done hot or cold and creates metal with a higher strength.
- Stamping – a metal sheet is hit with a die at high pressure to create a specific shape in the metal. A specific form of stamping, punching is when a press is used to force a die into metal creating a hole, many holes, embossing, or other shapes. The piece that is removed from punching is called the scrap slug and while normally performed on sheet metal, can also be done on rolled materials.
- Welding – when two piece of metal are joined together using fusion. Different types include oxy acetylene, tungsten inert gas, shield metal arc, and gas metal arc welding. Welding is done at a high temperature often with a filler metal material and can involved a chemical flame, electricity, pressure, or lasers to achieve the heater needed to join the metals.
- Machining – tools are used to remove pieces of metal from the piece being worked on. This can include drilling, filing, or grinding. Tools used to machine metal in the fabrication process include lathes, drills, and mills. Lathes are used to turn the metal piece against the cutting tool, drills use a rotating cutter to refine or create holes, and mills involve turning the cutting tool instead of the metal piece being worked on.
After a metal part goes through all of the metal fabrication steps required to create the desired shape and purpose, the piece is usually sand blasted and painted before being inspected and shipped to the customer. Metal fabrication is used across many industries employing over 1 million workers as welders, ironworkers, blacksmiths, machine setters and operators, assemblers, solderers and managers.