Question:
(a) NACE MR0175/ISO 15156-3, Sub-clause A.4.2, Table A.14 permits sulfur at 300°F in any H2S partial pressure, but not at 425°F. Where, if anywhere, between 425°F and 300°F are alloys in this category sulfur-resistant? If an oil-company client has a well with bottom-hole temperature of 350°F with produced brine that contains sulfur, will an alloy like 2550 (UNS N06975) be sufficiently resistant,
(b) must C-276 (UNS N10276) be deployed?
Answer
(a) In some cases the comparisons you make are not strictly valid because the data sets for the materials considered vary in the H2S limits, in the temperature limits, and in the metallurgical limits that are imposed. It is thought that the limits given are conservative and further testing could demonstrate that the true limits are less restrictive than those shown.
(b) UNS N10276 would be acceptable.
This question is in relation to NACE MR0175/ISO 15156-3 A.4.2, Table A.14 and A.33
Reference: ISO 15156 Maintenance Panel Inquiry #2003-13 Q4
With a wealth of experience in the oil and gas industry, we provide independent materials and corrosion consultancy to help companies reduce risk, save money and apply best practice in their oil and gas businesses.
Find out more by getting in touch – you’ll get an answer from a qualified, experienced materials engineer every time.
US: 877-399-1010 (toll free)
UK: +44(0)1144000850
66 Eldon St
Sheffield
S1 4GT
United Kingdom