While metal tubes can be formed into a variety of shapes, square and round tubes are two of the most common for a variety of applications.
Getting an answer isn't as simple as looking at the space where the tube will be installed or just considering what the tube will be used for.
While shape is the obvious difference, there are some key factors to consider when deciding which tube style is best when bent and subsequently put into service.
There are three important factors to consider when comparing square vs. round tubing.
Although its shape does not lend itself to the impression of a tube, square tubing does perform better in some applications. Because of its flat surface, square tubing makes it easy to attach bolts and other objects to it. It can also be made to fit closer to nearby objects, thus reducing wasted space.
As with its cylindrical counterpart, square tubing has a variety of applications. It is commonly used for fencing, railings and building construction.
Square tubing requires more fabrication work, but it does not require as many specialized measurements as round tubing.
Metal coils are machined into a flat plate through a series of molds. The metal is then bent four times and welded from the inside to form a square.
In a single, unbent part, square tubing offers superior strength. This is why it is used in building construction or to create barriers.
Its vertical edges combined with the way it distributes tension cause square tubing to lose some of its strength under pressure. The stresses on square tubing make it more susceptible to deformations such as rippling and buckling.
Square tubing is more likely to yield under pressure than round tubing.
However, its shape does allow for better fabrication - it is easier to cut and weld into specific shapes to fit into unique spaces.
When most people think of tubing, they immediately think of round parts. And for good reason too - round metal tubing is used in a variety of applications, but it is most commonly used to move fluids.
Because of its shape, round tubing requires less material to produce, making it lighter in weight and less expensive to manufacture. Metal coils are machined into thin sheets and formed into circles before being welded.
Round tubes are also easier to thread, seal and insulate.
Unlike rectangular tubing, round tubing has a continuous surface with no edges. When subjected to pressure, the pressure is evenly distributed. This reduces the chance of unwanted bending, breaking and curling.
Compared to rectangular tubing, cylindrical tubing is stronger because it has no weak points at corners and has consistent strength along its internal and external surfaces. It is also more resistant to bending and twisting under weight.
Round tubing is the best choice for bending and forming.
Due to its cylindrical shape, the metal will flow evenly in all directions when bent. When bent properly, there is little risk of denting or warping.
The simple answer to this question: Round tubing is ideal for bending.
Its strength and formability make round tubing significantly better than square tubing. Other attributes, such as ease of fabrication and manufacturing, make it an attractive choice.
However, when considering which shape of tubing to use, it is important to remember that every project and application is different.
When manufacturing cost, strength and bendability are key issues for a project, round tubing is the clear choice.
In some applications, square tubing makes more sense - especially if you are installing it where the shape of the tube is important. Think about it: a tight space with a sharp turn, such as inside an appliance.
Ready to learn more about tube bending services?