Mechanical Tube Expansion

There are many cases when it is necessary to expand a metal tube. It may be to create a mechanical joint or allow the section of tube to attach to a certain fixture. In either case, it is a challenging process and must be precise to ensure a snug fit that won’t allow leaks or cause instability. At Multiform Tubes Engineering Ltd we have a lot of experience in this area. In fact, we are an authority on mechanical tube expansion.


Mechanical Tube ExpansionTo expand tubes accurately you need to begin by measuring the wall thickness, inner diameter, and outer diameter. You can then determine exactly how much you need to expand the ID to get the right fit.

It is also vital that you consider the type of material you are dealing with. Metals have different characteristics and behave differently when you work them. For example copper is soft and easier to work with. As a result you can expand the ID by up to 10%. Stainless steel on the other hand is much harder and hardens as you work it. Therefore you may only be able to expand the ID by 4-5%.

Methods of expansion

Tube bending servicesWe use two different methods in our mechanical tube expansion services. Firstly we can use static tapered dies. The die will be the exact size and diameter for the project, made to expand the tube by the precise amount. Substantial pressure slowly forces the die into the end of the tubing. Because of the shape, it expands the tube by compressing the wall. This is a cost effective method but it can only expand the tubing as wide as the die.

The second option is using a hydraulic expanding die. This is different to the static one because it has segments that can open. The hydraulics control these, opening them slowly to expand the tube. This option offers a much wider range than a static die because the segments can open as much or as little as you decide.

We choose the right method for each project, ensuring we can expand the tube accurately to the exact dimensions. We always consider the material we are working with so we know how to deal with it.

Work with a top provider of mechanical tube expansion

If you want a first rate service, we are the team for you. We have the capacity to handle any order size and always ensure consistent quality. In addition, we work very hard to offer excellent customer service. As part of this we can answer questions, offer advice, and cater for special requests.

To learn more about our services or arrange one, please contact us today.