Massive Infrastructure. Zero Compromises.
Fabricating steel structures for highway bridges, railway crossings, and massive pedestrian overpasses represents the peak of structural metalworking. Bridges are subjected to dynamic vehicular loads, high wind stresses, and relentless environmental corrosion, demanding flawless execution in both materials handling and deep-penetration welding.
The Project Scope
For this specific heavy infrastructure project, Openex was tasked with manufacturing multiple spans of massive steel box girders and truss bridge assemblies. Due to the extreme lengths involved, field welding had to be minimized. Openex fabricated complete drop-in segments in our shop, verifying complex structural geometries and required camber through our vast indoor floor space.
Engineering Challenges & Manufacturing Solutions
Challenge: Gigantic Proportions
Bridge girders run exceptionally long and are notoriously difficult to maneuver. Keeping the segments aligned for pristine welding pools is extremely challenging.
Utilized 250-ton overhead cranes alongside massive automated head-tailstock turning rolls. This allowed operators to rotate whole bridge girders 360°, maintaining high-deposition 1G (flat) Submerged Arc Welding.
Challenge: Stringent Welding Codes
Bridge construction typically mandates absolute compliance with AWS D1.5 Bridge Welding Code, demanding zero internal defects under heavy vehicular cyclic loading.
Our on-site Level III NDT team administered 100% Phased Array Ultrasonic Testing (PAUT) and Radiographic Testing (RT) on all primary structural load-bearing seams.
Bridge Fabrication Parameters
| Metric | Project Specification |
|---|---|
| Total Structural Weight | Excess of 3,500 Tons |
| Material Graded Utilized | ASTM A709 Grade 50W (Weathering Steel) & Grade 50 (HSLA Carbon Steel) |
| Certifications & Standards | AWS D1.5 (Bridge Code), CE EN-1090-2 EXC4 |
| Advanced Finishes | Full enclosed grit-blasting (Sa 2.5) followed by multi-coat marine-grade epoxy systems. |