Sheet metal fabricating usually begins with a large sheet of galvanized metal. This sheet is measured and marked according to the purpose it will serve. Fabricators then cut the metal to the desired size using a variety of tools. This process is also known as shearing as it involves applying force to cause the metal to shear. Sheet metal cutters and shears are also used at this stage. Other tools include powered and non-powered saws, chisels and torches. CNC plasma cutters are also commonly used to produce quick and precise cuts.
Once the sheet metal pieces are cut to the right size, the next step is forming them to the desired shape. Each piece must have a specific shape depending on its function and location within the larger system. Some shaping can be done by using hand tools, but mechanical equipment is often required. A fabricator has many tools at their disposal to help them achieve exactly the shape they need. Here are just a few of the tools that may be used during fabrication.
Folding machines are used to fold sheet metal at sharp and precise angles. Flange forming machines press flanges into sheet metal to make joining easier. Notching machines can shear sheet metal at precise angles to create corners. Pneumatic corner mounting machines are used to form corners from rectangular ducts. Shrimp bending machines bend pipes and ducts to create elbow-shaped “shrimp” bends.
The goal of forming is to apply pressure to deform the metal without shearing. The forming process is where flat, cut sheets of metal are transformed into the parts needed for the job. Fittings and other necessary pieces are also formed at this stage.
Once all the necessary pieces have been formed, the final task is to put them all together. This stage is particularly important to ensure that every piece works as intended. A single misaligned duct section or poorly installed plenum can hamper an entire HVAC system. The assembly stage is also the time for any final adjustments to maximize fit and efficiency.
The actual process of assembling varies depending on the application. Often, the pieces are joined together by welding. Other applications may use threaded fasteners, rivets, powerful adhesives or some combination of the above. Sometimes, pieces are joined together by crimping specially made seams. Some assemblies may also require a final step called finishing. This involves applying a durable powder coat treatment.
A well-designed HVAC system is an important component of any business. A system that’s tailored to meet your specific needs can lower utility costs and save a lot of headaches long-term. Sheet metal fabrication is an essential part of ensuring the perfect fit and function.
To learn more about how you can benefit from HVAC fabrication and design, get in touch with our team at Jarrow’s office.