Completion Design, Installation, and Performance—Cannonball Field, Offshore Trinidad

Abstract

Summary The Cannonball field is a one-trillion cubic ft gas-condensate development in offshore Trinidad producing at an initial rate in excess of 800 MMcf/D from three wells. The completion design selected was 7"-in. production tubing with an openhole gravel pack (OHGP). The initial well (CAN01) has produced at an initial rate of 320 MMcf/D. The calculated deliverability of this well is 415 MMcf/D. This paper discusses the completion basis of design, detailed engineering assurance of the design, qualification of critical engineered equipment, and actual results. Introduction Trinidad's gas production has increased dramatically over the past 10 years. In 1996, local gas production exceeded oil production for the first time as the twin island Caribbean state of Trinidad and Tobago moved from a predominantly oil-producing country to a major gas producer. The gas growth has been driven by an increase in local demand and construction of a liquefied natural gas (LNG) infrastructure, which now includes four trains. The company's share of the gas supply to the local market has grown from less than 350 MMcf/D in 1994 to over 2 Bcf/D by mid 2007 with production coming predominantly from several prolific gas fields located off Trinidad's east coast (Fig. 1). The Cannonball field is located approximately 35 miles off the southeast coast of Trinidad in 240 ft of water (Fig. 1). The discovery well, Ironhorse-1 ST1, was drilled in 2002. In 2005, a minimal structure (nine-slot, four-pile) production platform was installed, and three development wells were drilled and completed with a jackup-cantilever drilling rig. Initial production commenced on 12 March 2006 following pipeline hookup and commissioning. The Cannonball field was brought on production at a sustained rate in excess of 800 MMcf/D. "Trinidad's First 500 MMcf/D Well: Fact or Fiction" (Kronnah et al. 2003) discussed the Ironhorse discovery well and presented the engineering challenge of an ultrabore completion (9"-in. production tubing). The right scoping process discussed in this paper presents the various tubing sizes evaluated and articulates the decision to select 7"-in. production tubing.