30-Inch Crude Pipeline Repairs

Sea Engineering, Inc. was contracted to provide engineering design and planning, vessel, and diving services for the installation of a 26-ton (52,000lb) structural clamp onto a 30-inch Crude Oil Pipeline.  SEI worked with the project owner through permitting and installation planning support, providing design and fabrication drawings for the A-frame structures to relocate existing pipeline anchor blocks as well as the pipe clamp halves.  SEI crews also completed excavation and removal of over 40 cubic yards of seafloor material for pipeline access for the clamp design measurements and during installation.  SEI dive crews utilized their 74ft landing craft ‘Huki Pau’ to support the offshore excavation work and initial anchor block relocation efforts.  Clamp halves were placed on the seafloor through a team comprised of Sea Engineering, Inc, Healy Tibbitts Builders (https://www.healytibbitts.com), and Hawaii Resource Group (https://www.pmtugs.com/home/hawaii-resource-group-maritime-division/).  Once clamps were on the seafloor, SEI crews utilized their 84-ft dive support vessel, ‘Kūpa’a’, to locate clamp halves within the future A-frame footprint.  Once relocated, SEI crew loaded the A-frame assembly on-board the ‘Kūpa’a and completed the final fabrication onsite.  The clamp halves were then positioned on the pipeline and tensioned together using an INTEGRA hydraulic bolt tensioning system.  The project was completed over a 2-year period, due to weather constraints at the site, with zero injuries or un-scheduled shutdowns to the pipeline.