Offshore oil extraction is advancing into ever deeper regions of the sea. As the connection of the boreholes with the production platforms is not possible with rigid piping, flexible hose lines were developed.
These so-called flexible pipes have to withstand the water pressures at depths of 2000 m and more. Consequently, one or two layers of profiled steel wire are integrated into the hose as pressure reinforcement. Here, typically C or Z profiles (figure, right) are used.
In addition to this pressure reinforcement, flat wires are used for tension reinforcement to accomodate the weight forces.