Single-Trip Multizone Gravel-Packing Case History Improves Anticipated Production from the Berantai Field

Abstract

The Berantai Field is a marginal sand-prone formation located offshore in the Malaysian Peninsula, and its development was chosen for Malaysia's first and second Risk Service Contracts (RSCs) to provide gas production within two years of the Field Development Project (FDP)'s execution. This field was initially considered as marginal with only an estimated 44 mmstb of oil and 440 mmscf of gas. A key performance requirement was to complete and produce the gas wells, sand free at the targeted production rate of 150 mmscfd. However, during development of the field, up to twenty multilayered, unconsolidated sand formations that had not been forecasted in the FDP were discovered, increasing the challenges for the completion strategy. The dual-string single-trip multi zone (STMZ) system was selected for the completions, as this technology had been proven to provide cost-effective, single-trip gravel-pack applications that could reduce overall cost, since the gravel packing for multiple zones could be performed in a single trip. Although completing long intervals has unique challenges for fixed- interval spacing, and the initial campaign presented other challenges, all seven wells were successfully delivered. A total of thirty one zones were treated. One of the wells not only had six gravel-packed zones completed in one trip, but also had the world's longest concentric wash pipe used in any dual string STMZ completion. This paper will show how proper completion planning and dual string STMZ technology enabled the operator to deliver the committed gas production, saved ~150K USD per gravel-packed zone, and reduced approximately 2.2 days in average rig time per well. The challenges addressed during this campaign, the methodology followed in the completion design, detailed completion and pumping strategy success factors, and the production results obtained from this marginal field development will be presented.