Case Study

Amethyst Semi-Submersible
Oil Drilling Rig
Portland Harbor, Maine




High Resolution 3D laser scanning technology was used to digitally map the vertical interior of containment vessels on the oil rig to facilitate structural modifications. The accurate determination of structural spans prior to fabrication minimizes costly field fit modifications. Rapid conversion of field data to as-built drawings was essential to avoid schedule delays.

Petrodrill is the first U.S. company to employ the "floatover" mating process. Cianbro, one of the East Coast's largest construction and construction services companies, submerged the pontoons while moving and aligning the 5,500-ton deck box onto the columns to successfully complete the mating phase of construction. Cianbro completed the construction of two, 12,000-ton offshore, semi-submersible, oil drilling vessels for Petrodrill.