In most circumstances, metal that is used for pipe fabrication needs to be heated before it can be bent into shape. However, there are some instances when heating metal isn’t an option. Some metals can be bent cold if the right process is used. It isn’t recommended for certain metals such as brass as it can cause them to crack or even shatter. In addition, it isn’t recommended for smaller bends since it can cause smaller bends to kink. Most of the time, cold bending is used for pipes or tubes that require larger bends.
Cold bending is also known as roll bending because of the process most commonly used to bend metal that hasn’t been heated. Roll bending is accomplished using a mechanical jig that uses three rollers to bend metal into a circular arc. The two outer rollers are usually immobile and are used to hold the metal in place, while the third roller places pressure on top of the metal, creating the large bend that is needed for the project. The process is particularly useful when bending sheet metal. Bending pipes and tubes in this way is more difficult, but it can be done.
Other Cold Bending Methods
Cold bending can also be done through other methods, although it isn’t always recommended. Bending metal that hasn’t been heated is as difficult as it sounds, and there’s a reason why most professional companies use roll benders. However, cold bending metal is possible with a vise and a pair of tongs. The metal is held tightly in place by the vise, and the tongs are used to grip and bend the metal. Alternatively, some metalworkers like to bend sheet metal or rods around an anvil. Neither method provides as smooth or precise a bend as roll bending, but they are also used when it isn’t possible to bend heated metal. For the best results, cold bending is the way to go.
Why Cold Bending is Necessary
Cold bending, particularly when it is done using a roll bender, can be used when there is no way to heat metal before it can be bent. It is also utilized when it is necessary to have a large, smooth bend in a pipe or with sheet metal. Pipes in particular, need to be have gentler curves in order to accommodate water or other fluids that may pass through them, and cold bending is sometimes the only way to create these curves and large bends. Cold bending is also cheaper in many cases; the equipment and materials needed to work with heated metal are expensive. By working with cold metal whenever possible, pipe fabricators and metal workers can save on production costs. Finally, some metalworkers find that cold bending creates more aesthetically pleasing final products, with smoother finishes and gentler curves that often aren’t possible through other methods.
In general, working with heated metal is much easier than cold metal, and it is usually the preferred method for most metalworkers. However, those who want to create large bends with gentler curves when fabricating pipes or bending sheet metal find that cold bending is often necessary.