Sheet Metal Fabrication Process and Techniques
The sheet metal fabrication process is a vital part of the many technological advancements. We’ve seen these advancements in fields like aerospace, electronics, medicine, and many more. Metal fabrication is key in producing aviation gauges, such as the casing for these meters. Metal fabrication is also key in aviation instruments. These necessary tools for aviation rely heavily on sheet metal fabrication for housing and operation. Sheet metal fabrication is largely responsible for the production of metal devices, particularly electronic ones. Most of the equipment in a hospital or doctor’s office is dependent upon metal fabrication–from apparatus to monitor the heart to x-ray machines to look inside the body.
These processes and techniques include cutting, bending, assembling, welding, powder coating, turret & laser automation, sub-contract manufacturing, prototyping, machine design, and technical drawing. These processes and techniques require extreme precision and have little tolerance for error. Advancements in the previously mentioned industries are only made possible through the ingenuity and dedication of fabrication professionals like Midwest Metal Products.
Forming
Taking a closer look at the process of metal fabrication, we’ll examine the forming press Midwest Metal Products. A press takes on many forms but the general function of this machine is to transform metal into the general structure of the product being developed. A press operator relies on the machine to perform three basic mechanisms of hydraulic, mechanical, or pneumatic.
- Forging – Forging presses are those that shape and distribute weight across a sheet metal much like a blacksmith would hammer out metal into the rough shape of a product.
- Braking – Press braking is the tool responsible for producing predetermined bends during custom sheet metal fabrication.
- Stamping – Stamping is the process of using a press with a mold to create specific shapes during sheet metal fabrication.
- Punching – Punching is the forming press responsible for producing the holes necessary during sheet metal fabrication such as those through which a screw will adhere to two metal structures.
Sheet Metal Fabrication Cutting
After the general shape is achieved with the sheet metal fabrication tools of pressing, the task of cutting can begin to get the sheet metal into a more desired size. The cutting process of sheet metal fabrication can be accomplished through multiple methods, including sawing, torching, or numerical control cutting. Each of these methods has multiple possible tools that can be selected depending on the particular specifications of a custom metal fabrication job.
- Chopping – The traditional chopping methods include sawing, shearing, or chiseling. Sawing is the use of a blade, chain, or wire to make cuts in metal.
- Sawing – Sheet metal fabrication tools used for sawing can include: a hacksaw, chop saw, jigsaw, and band saw.
- Shearing – Shearing is the use of a sheet metal fabrication tool that functions as a pair of scissors, including alligator shear, bench shear, guillotine, power shears, throatless shears, and tin snips.
- Chiseling – Chiseling is a sheet metal fabrication tool that comes in a variety of shapes with the designed goal of pushing through sheet metal.
Torching
It is also useful to note another technique in metal fabrication called torching. Torching is a form of chopping which relies on the principles of welding. Torching consists of two major forms of hand-held torches: oxy-fueled and plasma torches which are explained below.
- Oxy-fueled. Oxy-fueled torches combine oxygen with a fuel gas to maintain a heat that cuts through metal by melting it.
- Plasma. Plasma torches are a similar product. But, instead of relying on the relationship between oxygen and particular gases, this cutting torch relies on the heat produced by turning a gas into a plasma.
- Numerical Control cutting. Numerical control cutting is a state-of-the-art form of cutting which relies on computer-programmed cutting technologies for precise and accurate custom metal fabrication. The numerical control cutting can be a modified version of other forms of cutting. Firstly, torches, or can incorporate different cutting technologies. For instance, lasers, water jets, or mill bits. Finally, most sheet metal fabrication tools that rely on numerical control cutting incorporate multiple forms of cutting (e.g., saws, lasers, chisels, and torches among others) into a single cell or unit.
Finishing
After shaping, cutting, and forming, a metal fabrication product is finished. The main focus of finishing is giving the sheet metal product a smooth finish and a nice look. The first tool is designed to smooth the finish of the sheet metal: an abrasive blaster. Pressurized air or fluid propels a variety of abrasives against the surface of the metal. Those abrasives blasters can include bead blasting, soda blasting, and sandblasting. Below is an explanation of the finishing process that makes each final product look its best.
- Bead blasting – A bead blaster uses fine glass beads to clear debris.
- Sodablasting – Sodablasting is the release of sodium bicarbonate through pressurized air to smooth a metal surface.
- Sandblasting – Sandblasting sends grains of sand against a metal fabrication product to smoothen out the surface.
As you can see, there’s a complex process and sophisticated techniques that go into sheet metal fabrication. When you need answers, turn to Midwest Metal Products.