Currently, ultradeepwater single-trip multizone completions are commonly run (Techentien et al 2016). Looking forward, improvement and progress can be achieved by using run history, lessons learned, and best practices. In the Lower Tertiary of the Gulf of Mexico, multizone completions in which differential pressure ratings of 15,000 psi are necessary, all operational stages should be considered, including stimulation treatments and production depletion. To date, little information is published about specific downhole component design methods or standard qualification processes required by operators and/or service companies. The objective of this paper is to help educate the industry by presenting the approach of one service company to address the 15,000 psi Lower Tertiary challenge.
This paper discusses the innovative qualification processes of all subsystems, including the intelligent upper completion, interfacing intermediate completion, and the sandface lower completion. The proven success of the industry-standard 10,000-psi generation IV (Clarkson et al. 2008) multizone frac-pack system (Grigsby et al. 2016) provides an installation and operating standard that is used as a basis for a 15,000-psi pressure-rated multizone system. Operators were interviewed, internal discussions with all stakeholders were conducted, and thorough reviews of current and future regulatory standards were completed to develop this methodology. This paper presents the results of these discussions and reviews the downhole components using a detailed qualification process. It also discusses the test procedures for full system validation to satisfy operator and regulatory requirements. The result is a reliable 15,000-psi differential, single-trip multizone system that incorporates an intelligent completion string for interventionless zonal isolation, control, and monitoring over the life of the well.