Steel for hydrogen and the CO2 pipes of the future

Steel grades for the transportation of hydrogen must provide high analytical and internal purity. The low sulphur and phosphorus contents set in the steelworks, in combination with the reliable casting of the slabs, are essential so as to ensure a high degree of microscopic and macroscopic purity. The aim is to produce materials that are as homogeneous as possible and do not present any points of attack for hydrogen, the smallest known element. 

As opposed to hydrogen, the aggregate state of carbon dioxide plays a decisive role. The transportation of carbon dioxide is particularly challenging when the medium is transported as a supercritical fluid. This refers to the state of matter that is neither liquid nor gaseous. In this state, large quantities of carbon dioxide can be pumped in connection with low flow resistance. Due to the physical properties of supercritical carbon dioxide, however, increased demands are made on the strength and low-temperature toughness of the pipes. In order to meet these requirements, steel grades are being developed that are characterized by their particularly fine-grained microstructure. For this purpose, the concept of so-called grain refinement is implemented by way of reliable and precise thermomechanical rolling. The aim is to produce a material that is as resistant as possible while countering crack propagation to the furthest possible extent.
 
Salzgitter Flachstahl is already supplying hot-rolled strip up to a thickness of 25.4 mm, which meets these demanding requirements. 
Thanks to the strengths of the Group’s tube mills, the Salzgitter Group is making decisive contributions to the transformation of infrastructure and industry.