Tube bending services are a fantastic option for different types of tubing. With high quality benders, you can adapt the tubes efficiently and accurately. This provides big advantages over other options, including cutting and welding. However, you need to think about a number of key factors. One of the most critical is tube wall thinning. If you aren’t careful, it could result in serious issues in the future.

What is it?

The most important thing to remember is how tube bending works. It’s a mechanical process that physically deforms the product. You don’t add any additional material, so how does it work? Crucially, the elongation occurs by spreading out the material in the wall of the tubing. So, naturally there will be thinning on the extrados (the outer part of the tube bend). At the same time, the intrados (the inner part of the tube bend) compresses and the wall thickens.

In many cases the wall thinning will be acceptable. However, there are situations where it is actually a major defect. Keep in mind that the thickness of the tube wall has a direct impact on the strength. If it is too thin, it may not be strong enough to withstand the load. This can end in tube failure and big accidents. It’s a particular concern for things like boiler tubing.

What causes it?

To get the most from tube bending services, you need to understand how wall thinning happens and what you can do to prevent it. This can be the difference between wasting resources and energy to make products that will go right to the scrapheap and producing reliable tubing.

There are several key things to think about here. For starters, the rate of thinning will differ by materials. It will also be impacted by the equipment and tooling you use. The specifications matter too, particularly the wall thickness, outer diameter, and centreline radius.

A crucial thing to keep in mind is the importance of the centreline radius. The size has a direct impact on the level of stress on the tube. Critically, the smaller the CLR, the higher the stress. It will lead to a higher volume of wall thinning.

The choice of tooling and set-up also has a big affect. It is one of the main reasons to opt for professional tube bending services rather than attempting free bending. Using a mandrel is a good idea to support the tube as you bend it, but it can cause more wall thinning. It depends on the positioning of the mandrel relative to the bend die tangent and the tightness of the fit.

What to do?

If you want the best results, it’s a good idea to work with experts. Specialists like us know how to set up equipment properly for each job. This reduces the extent of the wall thinning. Most importantly, it ensures the final tube will still be thick enough to provide the required mechanical properties.

One thing to consider is whether to use a booster. It helps to move the tube forward during bending, reducing the stress on the outside radius. As a result, it will reduce wall thinning. However, you need to be careful, ensuring the boost won’t cause surface damage or issues with the clamp die.

Speak to us and discover how we provide exceptional tube bending services

Multiform Tubes Engineering Ltd understands the science behind tube bending and other processes. Therefore, we know what happens to the tubing and the impact it can have, including wall thinning and other flaws like inner wall wrinkling. We do everything we can to prevent these problems, providing quality tube for projects.

So, if you want to organise tube bending services, contact us. We provide drilling, end forming, and other solutions too if you want the same exceptional standards.