DNV GL: New approach to valve testing in subsea wells
DNV GL and ExproSoft are working together to offer a new approach to testing barrier valves in subsea completed wells that could reduce downtime, cost, and risk related to shut-in and restart of wells.
“In Norway, today’s current prescriptive approach to well testing can result in up to 3 days lost production per test, equivalent to $10M per asset.
“Changing today’s prescriptive test intervals and leak criteria to a risk and reliability-based approach, will achieve substantial year-on-year cost savings for operators in Norway and elsewhere,” said Kjell Eriksson, Regional Manager – Norway, DNV GL – Oil & Gas.
“Our experts can use established methodologies from the process industry and safety systems to reduce the number of shut-ins and well downtime, thus lowering the need for expensive interventions and work-overs. All this can be attained while maintaining acceptable risk levels and meeting regulatory requirements.”
Currently, the NCS regime refers to NORSOK D-010 for well barrier testing and testing frequencies, and leak criteria for well barrier valves are determined by API 14B/ISO 10417. The NORSOK standards are developed by the Norwegian petroleum industry to ensure adequate safety, value adding and cost effectiveness for petroleum industry developments and operations. The NORSOK standards are prepared and published with The Norwegian Oil Industry Association’s support.
DNV GL and Exprosoft will undertake a project to develop the risk based approach which will identify failure modes and causes, failure rates, analyze the consequences, establish a risk picture and translate the results into a recommended test frequency. The results can be applied globally and will be available in Q1 2016, DNV GL says.
DNV GL adds that its cooperation with Exprosoft brings together ExproSoft’ s WellMaster, a repository of data for wells based on more than 40,000 well years of historical data, with DNV GL’s risk management expertise.
“For an offshore platform with 25 wells producing 50 000 barrels a day, the average annual intervention cost is $26 Million,” said ExproSoft’ s CEO, Odd Are Svensen. “We are looking forward to working closely with DNV GL to combine our equipment reliability services with DNV GL’s risk management expertise to reduce intervention cost.”