Metal fabrication is much more than just welding, although the two terms often get confused. Metal fabrication involves the entire creation of a product made from metal. Fabrication involves all the steps in making a product including: cutting, bending and assembling structures.
Normally a fabrication shop will win jobs by studying engineering drawings, and bidding on the job. If the fabrication shop and employer can come to an agreement the fabrication shop will often utilize several different tools and specialists to create the product. In order to build the finished metal product both human labour and automation will most likely be used.
A fabricated product is referred to as a fabrication, and the places that specialize in creating metal structures are often called fab shops. The end products of other common types of metalworking such as machining, metal stamping, forging, and casting, may be similar in design and purpose, but while those individual processes may overlap with fabrication the terms are not interchangeable.
Processes
- Variations of Cutting include: sawing, shearing, or chiselling with manual and powered labour.
- Torching with handheld torches (such as oxy-fuel torches or plasma torches); and via numerical control computer operated (CNC) cutters using a laser, mill bits, torch, or water jet.
- Variations of Bending include: hammering or via press brakes, tube benders and similar tools. Today metal fabricators use press brakes to coin or air-bend metal sheets into a form. CNC-controlled backgauges use hard stops to position cut parts to place bend lines in specific positions.
- Variations of Assembling include: welding, binding with adhesives, riveting, threaded fasteners, or crimped seams. See our structural steel fabrication for more details.
Fabrication comprises or overlaps with various metalworking specialities:
- Fabrication shops and machine shops often have overlapping capabilities and processes, but fabrication shops generally concentrate on metal preparation and assembly. Machine shops cut metal, but focus primarily on machining of parts. Some companies offer both fab work and machining.
- Blacksmithing historically has been a part of fabrication.
- Welder-produced products are usually called weldments, and are products of fabrication. See our steel fabrication services.
- Boilermakers originally specialized in fabricating boilers, but the term is now used more broadly.
- Millwrights originally specialized in setting up grain mills and sawmills, but now perform a wide range of fabrication.
- Ironworkers also participate in fabrication. They generally work with prefabricated segments, produced in fab shops, delivered to site. Learn more about our construction steel.
Raw materials
Standard metal fabrication materials are:
- Plate metal
- Formed metal
- Expanded metal
- Tube stock
- Welding wire
- Welding rod
- Casting materials — see our casting guide.
Cutting/Burning Process
There are a variety of tools that can be used to cut metal, these include: cutting torches, band saws, chop saws, plasma, laser and water jet cutters. Commonly, metal is cut through burning or melting (shearing).
Unique band saws for cutting metal have hardened blades and feed mechanisms to ensure straight cutting. Chop saws are similar to mitre saws but use abrasive disks suitable for cutting steel. Cutting torches use heat to easily cut large sections of metal. Burn tables are a type of CNC cutting torch powered by natural gas.
Plasma cutting uses a stream of hot plasma. Laser cutting uses a laser to slice materials. Water jet cutters use high-pressure water with abrasive. Higher-end tables may use CNC punch technology or robots. Learn more about our sheet metal fabrication.
Forming Metal
Forming includes rolling, bending, deep drawing, extrusion, drop forging and open die forging. It changes metal shape without altering mass. Forming is used in jewellery, aerospace, automotive and architectural work. Forming may also combine with welding to produce large lengths of fabricated sheeting. Read more about structural steel.
Machining Metal
Machining involves removing material using lathes, mills, drills and handheld tools. Machine shops perform machining, though many fab shops also have machining capability. Small metal parts such as bolts, screws and nuts are machined components. Related: universal steel beams.
Welding Metal
Welding is generally the main focus in steel fabrication, but welding and fabrication are not interchangeable. Parts are usually formed, machined and assembled before welding occurs. The parts are tack-welded, checked for precision, then finally welded. More on metal fabrication.
Welding can be complex due to warping. Sometimes products need redesigning to reduce welding. If warping cannot be avoided, post-weld straightening may be required. This requires skilled welders and tools such as oxyacetylene torches. Residual stresses can be relieved by annealing in a low-temperature oven.
Assembling
After welding, the product may need sandblasting, priming and painting. All extra manufacturing occurs before final inspection. Explore our powder coating services.
Uses
Fabricated products are essential in the construction of steel frame buildings, mezzanine floors, and steel balustrade.