Tube bending is an art, and just like any other art, it requires, skill, inspiration, passion, and precision in executing a vision. Otherwise, the finished work comes out underdeveloped.

With tube bending, one of the biggest obstacles you face is flattening of the tube shape. Sometimes, a little flattening can be okay. Around 15%, or so. Other times, you need to maintain that perfect circle with virtually zero flattening.

For this, you’ll need to use a mandrel.

Mandrel Bending Basics

Just to make sure everyone is up to speed, let’s recap what exactly mandrel bending is.

A mandrel is an object, typically a metal rod or ball, that’s inserted into the tube and held at the point of bending. While the tube is pulled and bent, the mandrel holds the interior radius in place, preventing the tube from collapsing on itself.

For particularly tight bends, as well as the bending of tubes with thin walls, a wiper die may be used to prevent buckling.

The end result is a bend that’s superior inside and out.

The Benefits of Mandrel Bending

The benefits of mandrel bending stem from superior shape and structural integrity. Mandrel bent tubes are simply stronger at the points of bending than tubes that have undergone empty bends. They can handle more pressure, and they last longer.

Additionally, because they’re smoother and more open, they perform better in certain uses. Mandrel-bent exhaust pipes, for example, can achieve more horsepower and torque, as well as higher fuel efficiency.

Do I Need Mandrel Bending?

You may think that mandrel bending is a no brainer. While it a superior form of tube bending and a great choice for many situations, it might not always be what you need. Where cost and speed are the highest priority, an empty bend might be the right way to go.

The best way to determine the bending method you need is to consult a professional.

At Ever-Roll, we specialize in all kinds of tube bending, from mandrel bending to CNC bending and beyond. Whether you need springs, piping, or tubular burner rings, we can handle the job efficiently. Contact us today.