Hardox overview Docol R8 Tube - Racing just changed forever - Docol
Docol R8 tubes


Docol® R8 Tube is a high strength steel that is stronger, safer and more consistent to work with. It allows you to create racing chassis and components that deliver the highest performance.

Tight tolerances, consistent performance

Other materials often contain variations that behave differently, even if they have the same design. The uniform properties of Docol® R8 tubes makes it possible to develop structures and chassis that deliver the same high performance, over and over again.

Uncompromised safety

Docol® R8 Tube features excellent ductility, which leads to a reduced risk of fracturing – something not only beneficial during a crash, but also in the event of driver rescue. Tests have shown that cutting through a crashed chassis is easier with Docol® R8 tubes. The Docol® R8 structure has a greater fatigue cycle and is less likely to stress fracture in the heat affected zone.

Easy to weld

One of the advantages that Docol® R8 Tube can offer racing engineers and mechanics is its weldability. Due to low alloy counts and a clean oxide-free surface, Docol® R8 Tube is easily welded to other types of steel. Pre-heating is not necessary and the characteristics of the weld zone are close to the parent material.

Reviewed and approved

The Docol® R8 Tube has been extensively tested and reviewed, and is SFI approved. The Docol® R8 Tube is formally approved by NHRA, SCCA, BMW Car Club, Powri and Can Am Sprint Series. It is used in drag cars, sprint cars, midget cars, motorcycles, sports cars, late models, modifieds and go karts.

Docol® R8 Tube hard facts

How to weld

Docol® R8 Tube features excellent weldability and has a low risk of welding defects due to the low CE-value, low amount of impurities and a clean oxide-free surface. To reduce the width of the HAZ as much as possible, we recommend that you keep the heat input as low as possible.
For both TIG/GTAW and MAG/GMAW the following filler material is recommended: AWS A5.28 ER80X.-X and AWS A5.28 ER110X.-X. Welding parameters might need to be adjusted.

Roll-formed and welded

Docol® R8 Tube is roll-formed and welded. Due to the low alloy content, the characteristics of the weld seams are very close to the parent material. On most dimensions the weld beads are removed, leaving the tubes in perfect circular shapes that can be handled regardless of the location of the weld seam. This allows for the tubes to telescope inside each other. 
The cross section of Docol® R8 Tube provides consistent wall thickness and a well-centered hole.

Bending circular tubes

Bending of Docol® R8 Tube can be done with commonly used bending tools. Depending on the diameter and thickness of the tube, a mandrel and ball may be needed to avoid buckling or wrinkling. 
The minimum bending radius for a 90° bend is 2.5 x ø. The maximum allowable diameter reduction in the bend is 5 %.
See where to use Docol