Duplex 2205 T-Section for the Tintagel Castle Footbridge
The Tintagel Bridge is a footbridge at the historic heritage site of Tintagel Castle, replacing a crossing lost between the 14th and 17th century and reconnecting the mainland to the headland where the castle ruins stand. The bridge consists of two independent cantilevers that nearly touch in the middle, designed to ease access for visitors to this legendary site, associated by tradition with King Arthur. The structural T-sections forming the bridge were specified in duplex stainless steel 1.4462 (2205) for their combination of high yield strength and corrosion resistance in a permanently exposed coastal environment. Montanstahl produced the custom 70×60×15×10 mm T-section using laser-hybrid welding technology, compliant with EN 1090 EXC3, grit shot blasted, and delivered in special lengths to minimise off-cuts on site.
Why Duplex 2205 for a Coastal Footbridge Structure
Tintagel is a headland on the Atlantic coast of Cornwall, fully exposed to salt spray, wind-driven moisture, and the aggressive marine atmosphere of the North Atlantic. For a structural element in this environment with a design service life measured in decades, material selection is a long-term engineering decision. Duplex stainless steel 1.4462 (2205) combines the corrosion resistance of an austenitic grade with a yield strength approximately twice that of standard 304L or 316L. The higher yield strength allows slimmer structural sections for the same load capacity, which was relevant for a bridge designed to be visually minimal at a sensitive heritage site. The duplex microstructure also provides excellent resistance to stress corrosion cracking, a failure mode that can affect austenitic grades in chloride-rich environments under sustained tensile stress.
Laser-Hybrid Welding, EN 1090 EXC3, Grit Shot Blasted, Special Lengths
Montanstahl produced the T-section using laser-hybrid welding technology with a 5-axis robot, a process that combines the precision and low heat input of laser welding with the deposition capability of a conventional arc process. This allows production of almost any section geometry and size with minimal raw material waste, because the process works from commonly available stock sizes rather than requiring purpose-rolled input material. The approach directly supports short delivery times, which was a project requirement. Structural execution was to EN 1090 EXC3, the execution class applicable to structures with high consequence of failure where fatigue or dynamic loading is a design consideration. The finished sections were grit shot blasted to the specified surface condition before delivery. UK partner Millstock Stainless Ltd arranged prompt and safe delivery to the Tintagel site.
Application Context
This project sits within Montanstahl’s architecture, building and construction segment, where laser welded special profiles in duplex and stainless steel are specified for bridges, public infrastructure, and architecturally exposed structural applications in demanding environments. Coastal and marine-exposed bridges represent one of the most technically challenging procurement contexts for structural steel, combining corrosion exposure, structural loading, fatigue considerations, and heritage sensitivity. Montanstahl supplies custom duplex and stainless steel structural sections for bridges and public infrastructure projects worldwide, with EN 1090 EXC3 execution capability and grit blast or other surface finishing included as part of the supply package.