Laser Welded 347H Beams for Desert Solar Fields
A solar field built in a high desert has to survive intense radiation, wide daily temperature swings and abrasive dust for decades, with almost no opportunity for maintenance once the arrays are in place. For a large photovoltaic project of this kind, Montanstahl supplied 67 tons of IPE profiles measuring 270x135x6.6×10.2 mm in 347H stainless steel, produced by laser welding in accordance with ASTM A1069, with full weld penetration, precisely machined edges and a grit blasted and pickled surface finished to a roughness of Ra 3 to 5 micrometres.
A Framework Built to Outlast the Panels It Carries
In vast, sun-drenched desert terrain, an ambitious project is under way to harness solar energy and turn abundant sunlight into a sustainable source of power. Realising it means building an extensive field of solar panels, and that field needs a robust and reliable framework to carry the technology mounted on it. The project therefore called for high quality structural components able to withstand harsh desert conditions while providing the stability and durability the arrays depend on. The demands are unusual for a support structure. Ultraviolet exposure and temperature cycling work the connections continuously, wind-driven dust abrades any coating, and the mineral content of desert soils and occasional condensation attack the base of the structure, so a solution based on painted or galvanised carbon steel commits the operator to inspection and repainting across a site where access alone is expensive. Projects in the energy and power generation sector are increasingly resolved by moving that cost into the material itself.
Standards, Weld Penetration and a Defined Surface Class
Supplying supports for a project of this scale meant satisfying four requirements together. The quantity was 67 tons of IPE profiles, all produced by laser welding in accordance with ASTM A1069, the product standard covering laser and laser hybrid welded stainless steel shapes for structural use. The material had to be a stainless steel grade compliant with ASTM A240, which governs the plate the sections are built from. The welds themselves had to achieve full penetration, with the precision needed to manufacture sharp-edged profiles, because a partially penetrated joint in a structural member exposed to cyclic wind loading is a fatigue initiation site. The last requirement concerned the surface, specified as grit blasting followed by pickling to a roughness of Ra 3 to 5 micrometres, since a smoother and chemically clean surface strengthens the passive layer and improves corrosion resistance in service, and it also gives dust less to hold onto.
Application Context
Montanstahl produced 104 bars of 9,500 mm and a further 106 bars of 9,700 mm in 347H stainless steel, a stabilised austenitic grade that keeps its properties under prolonged thermal exposure. Each profile was designed to achieve full laser weld penetration with precisely machined edges, delivering the structural integrity the assembly required and letting the sections bolt together on site without adjustment. After production the profiles were shot blasted and pickled, giving a strong and durable finish that met the Ra 3 to 5 micrometre roughness the customer specified. Continuous dimensional and weld checks throughout manufacturing are part of Montanstahl quality management, which is what makes a supply of this size consistent from the first bar to the last. Sections of this family belong to the range of IPE beams, available in standard and custom dimensions and in a wide choice of grades, and further details are covered in the technical Q&A.