Abrasive Water Jet Cutting: Energy Resources Technology A CASE STUDY www.intermoor.com Abstract InterMoor’s abrasive water jet cutting system has been used for decommissioning of offshore platforms in the Gulf of Mexico since 2003. In July 2009, InterMoor crews removed a Guardian Platform in 88 ft of water. Site Details Location: ST138 Distance: 115.2 miles south of New Orleans Water Depth: 88 ft Operating Barge: D-85 Crane Capacity: 500 tons Platform Details Platform Type: Guardian Estimated Weight: 549 tons Conductors: 13 3/8 in, 20 in, 30 in Pin Piles: 2 each, 48 in Caisson: 48 in diameter opening up to 60 in diameter at mudline The Arrival Upon arrival at South Timbalier Block 138, the topsides had been loaded onto the materials barge. InterMoor personnel were transferred to the barge and set up their equipment while the structural supports were removed and sea-fastened for transport. When the barge captain was ready to begin the cut, the crew and equipment were standing by. Preparing for the Cut Prior to deploying the tool, a sounding was taken. The pile needed to be cleaned to a depth of at least 16 ft below the mudline so that the cut could be made at the regulation depth of 15 ft below the mudline. Barge personnel deployed the airlift and began jetting out the pile. As the pile was being jetted, InterMoor personnel pressure tested the tool to ensure the nozzle, hoses and pumps were functioning properly. In addition, they prepared the rigging to deploy to a depth of 103 ft from the pile top. Following the jetting, the depth of the sea floor within the pile was confirmed by another sounding.