Simply put, when any component is made out of metal, it is done by various methods that all fall under a process known as Metal Fabrication. There are various pieces of equipment utilized in metal fabrication including welding machines, rollers, press brakes, machine centers, turret punches, water jets, laser slicing machines, and simple metal shears. The metal fabricator will normally purchase the metal in the form of sheet bars or metal tubes and the metal used is usually stainless steel, carbon steel, or aluminum.
Sheet metal pieces are also a fairly common starting material, and this comes in various different thickness or "gauge". When a sheet metal piece is as thick or thicker than three sixteenths of an inch, it is known as a plate. The fabrication of these sheets can lead to components for countless various machines including, kitchen appliances, brackets, conveyors, augers, and many more.
Step one of the fabrication process is cutting the metal to size using a turret punch, metal shears, or a laser cutter. These shaping procedures take place with the metal still in it's flat form. Step two in the process involves bending the metal or "Forming". Forming is done with a "press brake" that is fitted with the correct die to make the needed bends in the metal called for by the pieces design. Depending on product, forming may be the final step, but some pieces still need to be welded.
The final step in the fabrication process is welding, which some consider to be an art form. Expert welders will create the finalized product by carefully welding all of the formed parts together to match the design plans. Experienced welders are trained in a number of welding techniques, and must decide which type of weld will have the greatest penetration for each joint and therefore be the strongest. The exact expansion and contraction tolerances of different types of metal as it heats and cools is also vital for the welder know. One of the most important tool used by a welder is the fixture, which holds the metal pieces together while being welded.
Besides sheet metal, two other types of starting metal forms used in fabrication are Tubing and Barstock. These are used to make a number of things including machine frames and railings. Tubing can come in several different shapes, including rectangular, square, and circular, and are normally about one eighth of an inch thick. This is know in the fabrication world as Schedule Forty Pipe or 10 gauge. metal tubing is used quite a bit in the industry because it is strong and light. The railing that you see on the side of a road or bridge is generally fabricated from metal tubing that is two to four inches thick and is incredibly strong. Although metal tubing is much lighter and less expensive than barstock, because there is less metal involved, the are cases where a solid bar is still needed. An instance where barstock is needed is in the production of shafts for screw conveyors. These shafts must be solid, because of the extraordinary pressure and torque that put on it by the conveyors motor while it is operating. Another example of when barstock is used is in railings for residential and commercial buildings. These railings do not have to have huge weight tolerances, and can generally be as thin as a half or an inch thick. When railings are fabricated from painted, galvanized, or stainless steel, it takes very little to maintain them, and they will last for decades.
Metal is used to make so many products because it is strong, long lasting, and requires very little, if any, maintenance. The metal that is produced by steel factories is taken by knowledgeable metal fabricators who use high tech machinery to form needed products that will stand the test of time.