As a rule, tube forming machinery must maintain a high level of accuracy. For this reason, tube forming machines are usually either automated manufacturing cells or dedicated machines. The main difference between the two is that automated manufacturing cells can be programmed to work on any number of applications, whereas dedicated machines are designed for specific jobs and cannot accommodate design alterations.
In general, tube forming machinery is quite diverse; among its ranks are: tube cutting machines, tube end forming machines, bending machines, tube notchers, tube rollers, and tube swaging machines.
Tube cutting machines are fairly self-explanatory: they cut tubing into different lengths and produce ends. They are very precise, allowing for both circular and square ends that are burr-free.
Tube end forming machines also perform cutting tasks, but they are created specifically to produce a tube end. As such, they can also perform chamfering, end expansion roll beading, end reduction, flanging, flaring, and notching.
Bending machines, which may also be called tube benders or tube bending equipment, curve and twist lengths of tube. Within this large group of machines are many smaller groups of machines, such as roll benders, rotary draw benders, and mandrel benders. During the process of roll bending, a tube is sent through a series of pressure-applying rollers that gradually change its bend radius. Likewise, pipe benders can perform a similar procedure on pipes.
Tube notchers, as their name implies, create notches in tubes. They do so by cutting down vertically and perpendicularly into the surface of the tubing.
Tube rolling is a process akin to tube fabrication that rolls strips of metal into tubing of all diameters. Almost identical and sometimes described interchangeably are tube mills, also known as tube mill equipment, which produce tubing or piping when they take a strip of metal and roll form it continuously until its edges meet, where they are welded.
Finally, tube swaging machines, or swaging machines, are cold metalworking machines that use high pressure or high pressure and a die to permanently join multiple tubes.
Other processes performed by tube forming machinery include packing, tube flaring, threading, coining, and nitinol heat setting. Packing is a bending process that works by filling, or packing, a tube with material that helps form it. One example of this is ice packing. During ice packing, a tube is filled with a water solution, frozen and then bent. This is made possible by the solution, which is equipped with properties that make the ice flexible. This technique is used to make trombones.
Another packing method is sand-packing/hot-slab forming. During this procedure, a tube is filled with fine sand then capped at its ends and placed in a furnace, where it is heated up to at least 1600℉. Once appropriately heated, the tube is placed on a slab with built-in pins. Here, it is bent around the pins using a mechanical force like a crane or a winch. The sand, which is removed once the tube has cooled, decreases distortion in the tube’s cross-section.
The objective of tube flaring is to form the end of a length of tubing into a funnel shape. This straightforward process is performed by tube end forming machines. Next, tube threading is the process by which the end of a tube acquires raised helical ribs, or threads. Tubes may receive external threading or internal threading. Either way, internal threading and external threading are designed to connect to each other and allow separate pieces of tubing to connect as well. In the context of tube forming, to coin means to flatten. So, coining is actually a process during which tubing is flattened by custom tools and dies.
Finally, nitinol heat setting is a much more specific process than those above. Performed only on nickel titanium, which is a half nickel, half titanium shape-memory alloy, in nitinol heat setting, tubing is forced through a die then baked at high temperatures. Baking is repeated several times until the shape is heat-set.