What is Metal Fabrication All About?Central Mobile Welding
What is Metal Fabrication?
This is a topic most perplexing for many newcomers to the welding industry. Often times, people have difficulty understanding the difference between welding and fabricating. Simply put, welding involves joining metals with high heat. Metal fabrication on the other hand, involves forming metals to various shapes, cleaning and preparing the metals before welding, flame cutting or drilling holes, and fitting component pieces into place before welding.
Different Types of Fabrication
Fabrication occurs in many different industries and in many different varieties. Some companies focus solely on fabrication, however many also provide welding services as well. This is because fabricated metal parts almost always need to be joined to other parts via bolting, clamping, or welding. Metal fabrication can be divided into two major categories: sheet metal fabrication, and heavy gauge fabrication.
Sheetmetal fabrication generally involves working with any metal that is under 1/8th of an inch thick. Metal thicker than that is usually considered a plate rather than a sheet, and would fall into the category of heavy gauge. Common processes for sheetmetal fabrication are rolling flat sheets into round shapes like cans or cylinders, plasma cutting patterns into sheets to create uniquely shaped parts, bending metal to create flanges, brackets or boxes, and drilling or punching holes into the metal. Some examples of sheetmetal fabrication are building exhaust systems for vehicles, making industrial molds, and fabricating some types of boilers on the smaller side. There are also endless applications of custom sheetmetal fabrication in industrial plants. This is because, often times parts will break through everyday use and need to be remade.
Heavy Gauge Fabrication
There are some metal fabrication shops that specialize in custom fabrication, and these are the most likely business to take on both sheetmetal and heavy gauge work. That said, most companies choose one or the other as the equipment required can be somewhat different. When getting into heavier gauge work, it becomes more common to have entire crews of people working on one project simply because of its size and weight. These materials can easily weigh hundreds, if not thousands of pounds, and usually require overhead hoists or forklifts to lift and move them from one area of the plant to another.
Some examples of heavy gauge fabrication include building heavy equipment like excavator booms and front loader buckets, fabricating heavy duty ceiling joists and trusses, making industrial staircases, building bridges, and preparing structural “I” beams with holes, brackets, and copes.
More Details on Metal Fabrication
While heavy gauge fabrication does use many of the processes used in sheetmetal fabrication, the equipment often differs because is it built to handle much heavier and stronger material. An example would be needing a hydraulic brake press to bend thick metal, opposed to using a manual bender to bend a thin sheet. Also, the expertise required to work with sheetmetal varies greatly from working with thicker metal. While thin metal can easily be hammered into new forms, thick metal often needs to heated before becoming more malleable. Sheetmetal also is much more susceptible to distortion when being welded, and therefore requires certain restraints or heat sinks put in place beforehand.
One process in fabrication that applies to both sheetmetal and heavy gauge work is the use of jigs. In order to speed up production, jigs are used to reduce the amount of time spent getting parts into the correct position. Essentially, a jig is a tool designed to allow multiple parts to fit inside it in a very specific orientation to one another. Jigs
are often used to orient parts before welding.
When multiple parts are merged into one final product, it is called an assembly. Individual materials that have to be modified in some way, or joined to other materials before becoming part of the final assembly, are called subassemblies.
Overall, metal fabrication is so varied that many companies focus on one specific niche due to the specialized skill required. For instance, there are only two major companies that manufacture steel ceiling joists in Canada, and their plants are over 700 feet long just contain the operations for that product line. This is a common trend with larger companies. It is more apt for smaller companies to have the flexibility to take on more varied work, though it is usually on a much smaller scale. As mentioned above, the extent of what a company can do is dependent entirely on the equipment, facility size, and skill of the workers that they possess.