Two platforms, pipelines, injection add 16 million bbl to Trinidad's annual production Installation commissioning of waterflood facilities on the Soldado Main Field offshore Trinidad is nearing completion. The purpose of the turnkey project, awarded to Houston division of Healy Tibbitts Builders by Trinmar in April 1991, was to recover an additional 16.8 million bbl of oil over ten years. Based on studies completed in 1989, Trinmar projected that, with waterflooding, the field would continue to produce at economical levels for another 20 years. Without the projected waterflooding, production would continue to rapidly decline. Located 15 miles west of Point Fortin in the Gulf of Paria, the Soldado Main Field turnkey project included engineering, fabrication, transportation, installation, hook-up, and commissioning of a 35,000 b/d water treatment and injection platform, a 36 MMcf/d gas compression platform, 15 miles of underwater pipeline and upgrading of associated offshore and onshore facilities. The construction program required five separate 2,100-mile ocean tows from the Gulf Coast to supply crane barges, materials, equipment, and the precommissioned assembled platforms to the site. The first tow, a tandem tow of two crane barges, the 110-ton capacity HT-541 and the 75-ton capacity HT-539, delivered bulk materials, equipment, and tools needed for offshore pipelines, onshore facilities and upgrading existing platforms. The second tow, the Weeks W-297 launch barge carried both jackets and their piles to the site and returned home to Louisiana for outfitting for the task of transporting the completed platforms to Trinidad. The 350 ton derrick barge, Weeks W-532, carried crew boats, pile driving hammers, and miscellaneous material and equipment to the site on the third tow. The Weeks W-297 was used in round trips four and five to transport and install the completed 550 ton water injection platform deck and the 900 ton gas compressor platform deck. The new platform sites are adjacent to existing operating platforms. A site-specific seismic hazard analysis revealed that the platforms are located in an intense seismic area. All structural elements were designed and fabricated to withstand high seismic loading. Geophysical investigations disclosed very poor bottom surface soils at each platform location. Due to the condition of the ocean floor, and the need to accurately position the structures, the water injection and gas compression platform jackets were hung on temporary piles until the jackets were permanently anchored in place by 180 to 195 ft long, 42-in. diameter steel pipe piles. Due to the seismic loading, pile wall thickness was up to 13/4 in. Healy Tibbitts elected to forego the more conventional installation procedure of using a heavy lift derrick barge, choosing instead to set both decks using a float-in technique. The structures were designed to allow the transport barge to be docked within the legs of the respective jackets. The decks were floated into position on a rising tide, the barge then ballasted down on a falling tide setting the deck legs on the jacket piles, and after further ballasting, the barge was withdrawn from under the deck. Research of weather and site-specific tide data provided definition of the environmental windows that minimized the motions of the barge and deck with respect to the jacket. Healy Tibbitts installed a supplemental ballast system on the cargo barge and cushioning assemblies, mounted on the jacket piles, to absorb the interactive forces between the deck legs and jacket piles during deck installation. The water injection deck was set in November 1992 and the gas compressor was set last February. Healy Tibbitts Builders is headquartered in San Francisco and is an affiliate of Weeks Marine.
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AuthorI'm Bruce O. Pratt, who thoroughly enjoys researching about Power & Hand Tools. I hope my reviews can help you to choose the right products fit with your needs. Archives
November 2017
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