Ram/Powell deepwater tension-leg platform: Horizontal-well design and operational experience

A key focus of the Ram/Powell project is to utilize high-rate (>20,000 BOPD ), high-volume wells (i.e., reserves several times greater than that of she lf wells) to enhance project profitability. Completions with large 51/2-in. production tubing and horizontal openhole gravel packs (OHGP's) exceeding 2,000 ft in length have been implemented successfully. The horizontal OHGP design, the first implemented in the deepwater Gulf of Mexico (GOM), was se lected as a means to improve well reliability over prior horizontal complet ion designs and sustain high production rates without plugging. A high rate of sand-control failure and plugging have plagued prior GOM horizontal non -gravel-packed completions. Achieving high-quality completions is a major p roject emphasis. Drilling, completion design, and operational experience of the horizontal wells are discussed. Production from the Ram/Powell tension-leg-platform (TLP) development, Shel l's third TLP, began in September 1997. The TLP is located at Viosca Knell Block 956 in 3,214 ft of water. Four wells were predrilled prior to TLP ins tallation. Ten wells are completed. Five are horizontal OHGP's, one is a si ngle-zone cased gravel pack, and the remainder are two- and three-zone-sele ctive cased gravel-packed completions. Rig operations concluded in January 2000.