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Abstract The word "integrity", is defined as: "the state of being whole, complete and entire, in an undiminished or unbroken condition". Well Integrity Remediation, therefore, is maintenance of well quality to insure such totality and undiminished condition. Well integrity has received a significant attention these days, from well conception to well abandonment. The driving factors such as the high oil price along with new techniques for Enhanced Oil Recovery (EOR) make it feasible and profitable to prolong the field life beyond original design. However, an extended well life has led to a higher probability of well integrity related problems e.g. Fatigue, Erosion and Corrosion. As case in point, PTTEP S1 - Sirikit Oilfield, experiences unavoidable well integrity problems, primarily relating to corroded casing due to water encroachment. In this respect, it is the sub-surface challenge to minimize the shut-in time and prolong overall well life. To address these problems, swelling elastomer was considered for a remediation work by isolating leak casing from production system, and thereby preventing further well integrity failure. Properties of inherent elastomeric substances is designed such that, when in contact with the wellbore fluid, will react and swell against the contacted surface providing long-term isolation with no mechanical intervention. The known product e.g. Swellable Packer has been proven for many years mainly for open-hole applications, until such a time as cased-hole remediation techniques are implemented by PTTEP. This paper examines case histories and demonstrates the practicality of Swellable Packer in the cased hole application which aging casings wall were chronically corroded by water encroachment. Two different types of wells: producer and injector, which casing confirmed failure by Production Logging tool (PLT) and Ultra Sonic Imager tool (USIT), were selected as candidates. The background, operation sequence and performance evaluation methodology are detailed on the following sections in this paper. |
