Flat-sided oval tube

Flat-sided oval tube (FSO) is a hollow structural section with two curved ends joined by two parallel flat faces. The profile combines the material efficiency of a tubular section with fixing convenience typically associated with box section — making it easier to integrate into fabricated assemblies than standard circular tube.

Essentially yes, it has significantly superior deflection strength when load bearing on the minor axis. In our own comparative testing, flat-sided oval tube has demonstrated up to 54% greater strength than an equivalent round tube. The advantage arises from the distribution of material in the cross-section relative to the bending axis. Contact us for test methodology details if you need to support a material specification or design submission.

FSO tube offers better ergonomics and grip comfort, a less visually heavy profile, and a radiused internal hollow section that can accommodate cable routing and inserts more effectively than square box. Its radiused corners make for a more friendly profile than sharply angled box section. Timeless Tube is able to form FSO in a wide range of sizes and finishes allowing you to select a tube that is fit for purpose (by contrast, box section is limited to a smaller selection of sizes and materials). Box section retains advantages for applications requiring maximum flat bearing surface or pure compressive load.

Yes — bending is available in selected sizes, and our capability continues to expand as we develop new tooling for fixed radius bending and continuous curves on our triple roller. We have also successfully coiled flat-sided oval in both planes, and folded FSO at acute angles using a press. Contact us with your profile size, wall thickness and required bend radius to confirm feasibility. If you only require a small amount of bending it may be more appropriate to mitre join the tubes at or use 3D-printed stainless steel connectors.

Yes. Flat-sided oval tube can be successfully laser cut or cold-sawn using standard equipment. As our tubes are cold formed from circular tube there is the possibility that the tube ends will spring open slightly when cut, so speak to us if you require the tubing to fit with other components and we can advise how to counter any spring back. We have also successfully laser-cut sections out of the centre of larger flat sided oval profiles to accommodate lighting and other electronic hardware.

Yes. If your required size is not in our standard range, contact us with your dimensions. We can discuss tooling options and lead times for custom profiles. Prototype quantities are available from one length, which is typically 5.7m for most stainless steel tube sizes in this profile.

Although we state an official ratio that we can comfortably achieve between the major and minor dimensions, we have exceeded this on multiple occasions to produce some surprisingly flat FSO tube. Send us your drawings or dimensions for advice, or read about the ratios for new sizes.

No, but we can produce a radiused rectangle profile — a variation with four flattened sides, created by processing FSO tube through a further forming stage. The result is a more angular profile with softened corners, well-suited to applications where the visual weight of box section is undesirable but a flatter fixing face is needed on all four sides. This is also known as oblong tube.