Performing your calculations for tube bending before you bend is a necessary, and sometimes tedious, part of the bending process. We’ve created a tool to help you navigate the bending calculations you’re likely to need, but it’s also important to understand why your calculations need to be correct.

What you need to know to perform tube bending

tubebendingequipment-300x200.jpgThere are a couple of pieces of important information you will need to calculate before you begin bending.

To perform a bend, the tube bender must have enough bend arm torque to overcome a material’s section modulus. If the bender does not have enough torque, the bend will fail to be permanent, or the material will be distorted or deformed. This is why calculating the section modulus as well as the torque is so vital for performing bends correctly.

The material composition is also important because it determines the deforming of the tubing material past the given material’s modulus of elasticity and into the yield strength of the material.

Some of the information you should know before you attempt your calculations for tube bending include the tubes outside diameter, the wall thickness, and the centerline radius. Of course, this is only a partial list so it’s important to refer to the formulas you will be using before beginning your calculations.

All in all, there are many variables that go into performing a successful tube bend. The calculations for CNC tube benders get even more tricky when dealing with non-round shapes.

Can you bend non-round tubes?

Yes. To understand how your bender will bend square, rectangular, and other non- round shapes you first need to calculate the section area moment of inertia for the round material and then compare it to the non-round material. As long as the round material number is higher than the non-round material, then that particular bender will be capable of bending your part shape.

It can be confusing to know which formulas and information you’ll need to perform these calculations, which is where our tube bending section modulus calculator can help.

What is the tube bending section modulus calculator?

The tube bending section modulus calculator allows you to input the tube specifications into an easy to use calculator. It then calculates the section area moment of inertia properties of common shapes.


Some of the most common shapes covered by the calculator are:

  • Square
  • Round
  • Half rounds
  • Triangles
  • Rectangles
  • Trapezoids
  • Hexagons
  • Octagons

What is in the Guide?

The Tube Bending Calculator Guide that is bundled with the calculator covers some of the most common tube bending formulas, including:

  • Tube inside diameter
  • Wall factor
  • Mandrel nose radius
  • Clamp length

Where can you find both the calculator and the guide?

Click here or follow the link below to download the updated Tube Section Modulus Calculator.

Related Articles
The ROI Of Tube Bending Automation Calculator

The ROI Of Tube Bending Automation Calculator

When considering a large capital equipment purchase, there are always a number of things that...
Read More
Tube Bending Calculator

Tube Bending Calculator

If you’ve ever had to perform the calculations necessary to properly bend tube and pipe you know...
Read More
Tube Bending Formulas Guide and the Section Modulus Calculator Together at Last

Tube Bending Formulas Guide and the Section...

Calculating the many variables needed to properly bend tube and pipe can be time-consuming. Finding...
Read More
Section Modulus Calculator Update: Tube Bending Calculations

Section Modulus Calculator Update: Tube Bending...

Earlier in the spring we offered our readers a Section Modulus Calculator to help with calculating...
Read More