Software-Based Deepwater-Blowout- Preventer Testing

Abstract

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper OTC 21688, ’Advances and Effects of Software-Based Deepwater-Blowout-Preventer Testing,’ by C. Mark Franklin, SPE, IPT Global; Tim Sargent, SPE, Noble Energy; Charles Brown, SPE, Hamilton Engineering; Gary W. Owen, SPE, Devon Energy; Steven Griffith, SPE, Shell; Jerry Osmond, SPE, Hess Corp.; Tore Gronas, Statoil; and Rick Cully, IPT Global, prepared for the 2011 Offshore Technology Conference, Houston, 2-5 May. The paper has not been peer reviewed. To advance the technology of blowout-preventer (BOP) leak detection through a software-development initiative, operators, service providers, and drilling contractors established an industry consortium in early 2009. The initial development focused on testing BOPs in deep water. Upon completion of the pilot program on five deepwater rigs, the results exceeded original expectations. The test results proved the software effective, efficient, and rig friendly. Introduction As drilling moves into deeper water and use of nonwater-based fluids increases, the challenges associated with obtaining effective pressure tests continue to grow. Prevailing interpretations of regulatory requirements to “hold pressure” have been to demonstrate a “flat line” on a pressure chart for a specified period of time. With the relatively low resolution of a circular-chart recorder (CCR), a flat line was produced, essentially, when the resolution of the device was not exceeded (typically 4–6 psi). Also, excessive damping and manipulation would not be recorded. Joint-Industry Project (JIP) During 2009 and 2010, four operators, with the support of several service providers and drilling contractors, participated in a JIP. As the main goal, the consortium wanted to develop state-of-the-art leak detection, with best practices for testing BOPs in deep water. The JIP was set up in two phases. Phase-1 gathered digital data from BOP tests performed in the Gulf of Mexico (GOM) and around the world. Archived data were used as test data, and a library of more than 100 data sets was built. Review of the test results showed that each data set had from 10 to 25 tests, 86% of which represented passing tests. The data archives provided insight into an automated approach for validating deepwater-BOP pressure tests. A software prototype was developed, along with workflow-automation features, and it was refined through multiple design-review meetings with the JIP members and the US Bureau of Ocean Energy Management, Regulation, and Enforcement. Phase-2 field-trial installations commenced on five deepwater rigs in the GOM. The software was also run in the background in a real-time operation center during BOP and manifold testing from multiple rig types (i.e., deepwater, tension-leg-platform, and jackup). The goal of Phase-2 was to validate the software and repair software issues.