Gold medal fabrication for Olympic ski jump - Company speeds

Tag : Tube Fabrication

"We had to be sure no shrinkage was happening on the tube,"Hildebrand said. "That's why the weld procedures were extremelycritical."
The company developed carefully crafted weld procedures, adheringto the AWS D1.1 structural welding code. Working with structuraltube trusses, welders couldn't use backing bars to dissipate theheat, which can be quite a challenge with full-penetration groovewelds up to 1¼ in. thick. For this reason, the company'swelders were prequalified to ensure they could lay the criticalroot pass without causing distortion.
Welder access also became an issue. The bracing angles from thechord members were sometimes severe, requiring a tremendous amountof weld prep, with some bracing tubes connecting at angles up to 60degrees (see Figure 3 ).
For the most part, the procedure called for open-root groovejoints. The welder would make the critical root pass, which wouldsubsequently be tested before making the remaining passes. Thesewere big welds, too, with some requiring 20 or more passes.
The fabrication of the jump sections steadily progressed, withcurved pieces resting on specially designed cradles, not unlikecradles for shipbuilding (the project was almost to that scale). Toensure smooth field assembly, workers trial-fit the massive pieceson the fab shop floor. Managers set operations within two long"lanes," one to handle the K95 jump, the other handling the K125(see Figures 4 and 5 )
It was a challenge to fit it all," Hildebrand recalled. "We'dfabricate the first section, and then bolt it to the second sectionas [other areas of the second section] were being fabricated. Whenthe first two sections were completed, we'd remove the firstsection, and bolt on the third section."
By the effort's end, the company fabricated six sections for eachski jump, ready for transport: 80 ft. long by 24 ft. wide by 12 ft.deep (24.38 by 7.32 by 3.66 m). And moving structures of that size,Hildebrand recalled, proved to be one of the most challengingaspects of the entire project. Moving to the Mountains