As children, most of us liked to bend metal. It might have been in the form of paper clips, or even some of your parent's cutlery. Some of us like making pipe-cleaner clowns. Or some just stuck to bending the toothpaste tube - as they used to be made out of metal then. One thing is for certain, and it is that the metal you were bending as a child was not steel beams or steel tubes. It also wasn't strong enough to maintain a stadium roof or a roller coaster in a fun park. Tubing benders are strong, sophisticated machinery.
All of us rely on curved metal beams, pipe, tubes, and angles in everything from a simple park bench to spiral staircases to some parts of modern skyscrapers. Visit any airport or museum built in the past couple decades and count the number of curved metal structures you find. Most of us never wonder how this is done - bending a steel beam and still keep the strength to support an airport roof. There are several ways that tubing benders operate.
Rolling is the best known tubing benders, perhaps because it is the least costly. Rolling uses an appropriate size die that adjusts to the steel tube, angle, pipe, channel, bar or steel beam and revolves at the same peripheral speed, turning in opposite directions. As the metal passes through the roll, the machine applies pressure as tubing benders or the beam to the desired radius. Rolling is effective when the material - metal, plastic, glass, whatever - must be bent a great deal. For instance, it can produce bends up to 360 degrees. This method is ideal for producing steel coils, spiral staircases and the like.
Mandrel tubing benders is also fairly well known. In this process, a metal shaft, or mandrel, is fitted inside the steel tube or pipe. As the mandrel moves, it bends the metal around the appropriate sized die to form the radius. Mandrel works best when the steel tube or pipe has a heavy wall and/or requires a tight radius because it prevents the material from rippling. Mandrel can only bend steel tubing up to 180 degrees, but it produces a bend that is uniform all the way up and down the pipe or tube.
The Press method is the third way that acts as tubing benders. The steel tube, pipe, channel, bar or steel beam is fed through the press, which applies pressure every 6 or 7 inches until the material is bent to specifications. Press is used to bend bigger, heavier beams, pipes, channels, bars or tubes that do not require a very tight radius. This is a less common process than rolling or mandrel. However, it is capable of producing large, load-bearing steel support beams used for schools, roofing, skyscrapers, gymnasiums, malls and bridges.
Table forming is the fourth process of tubing benders. The steel tube, pipe, or beam is laid out straight and the ends are pulled around the appropriate sized die to form the radius. Table forming is used primarily to bend smaller, heavier steel tubes, pipes, channels, bars or steel beams that require a tight radius.