Abstract:
Corrosion is the deterioration of the metals due to interaction with its environment. Most metals corrode because they are thermodynamically unstable in their environment and tend to return to their stable form: oxides, sulfides or other salts. Corrosion attacks every component at every stage in the life of an oil or gas field: from drilling platform, to production string, to storage and transportation facilities. It is estimated that costs related to corrosion are on the average 3% of all operational costs; up to 50 % of these costs can be saved through proper planning. This case study investigates the corrosion mechanism for two Qadirpur wells, Qadirpur-1 and Qadirpur-6, for tubing integrity. A high resolution multi-finger caliper tool was deployed for this purpose. A standalone corrosion monitoring was performed along with time lapse comparison with the base log conducted in 2005. The standalone analysis highlighted the occurrence of pitting corrosion commonly found in gas producing wells with Hydrogen sulphide (H2S) presence./ the time lapse analysis revealed the rate of corrosion occurring in the above mentioned two wells. A detailed analysis indicated that almost all the observed damage was caused by localized defects such as pits. Finally the results of both the standalone and the time lapse analysis were complied in order to determine possible root causes of the corrosion occurring in both of the tubing strings. It was also attempted to see what other elements might be contributing to the corrosion mechanism like CO2 percentage and produced water to determine future remedial plan.
Page(s):
209-218
DOI:
DOI not available
Published:
Journal: Proceedings SPE-PAPG Annual Technical Conference, Volume: 0, Issue: , Year: 2008