Fitness for Purpose Sulfide Stress Corrosion Testing For Alloys In Existing Wells in Deep Water Gulf of Mexico

摘要

Initial production in the deep water Gulf of Mexico has been underway for nearly 10 years. Secondary recovery methods are now in the planning stage. One of these methods is seawater injection. A number of operators in the North Sea have already started using this technique. Consideration of a water flood brings on the possibility of reservoir souring. For the Gulf of Mexico, a review of the materials of construction for existing wells found that well casing and completions were designed for sweet service, consequently a fitness for purpose testing qualification approach was undertaken. A fitness for purpose approach addressed approx 20 ppm H_2S in a condensed water phase (1 percent sodium chloride) and a number of alloys including P110, Q125, 8630M, 4130M. NACE TM 0177 test methods were utilized: uniaxial tests, double cantilever beam (DCB) fracture toughness test and bent beam tests, also known as Sc. Results and discussion are presented.