Perpustakaan Digital ITB

Since 2009, well integrity has cost operators over $75 billion with many well-publicized high-profile incidents. These accidents prompted the industry to evaluate and revise international guidelines for well integrity management. Well integrity issues are commonly associated with cement quality, casing corrosion, vigorous drilling and production pressures, also completion and abandonment complexities. The harsh conditions encountered in downhole environments unavoidably degrade the integrity of the well construction, for example, by corrosion or deformation of the steel pipes and mechanical or chemical deterioration of the annular cement sheath. (Nelson and Guillot, 2006; Kiran et al., 2017; Yousuf et al., 2021). The consequence of these well integrity issues is mainly the fluid migration over time within or escaping from the wells which can lead to production shut-down, explosion, and high-risk impact. A SINTEF study (SPE no.112335) from the North Sea in 2006 found that 18% of the wells surveyed are leaking. Furthermore, almost half of these 18% had the wells shut-in due to integrity issues. Managing the integrity of mature well inventory to avoid unwanted movement of fluids within a well, failure of sealing elements, corrosion, and especially leak has been no less crucial than any other activity to maximize production and injection. It needs a system to facilitate the decision-making process of managing well integrity issues. This study analyses well integrity problems that occurred in a well using well integrity management system in a form of a risk assessment matrix as a decision-making tool through a series of qualitative and quantitative analyses. Monitoring data analysis identifies casing leak as the main well integrity problem that occurs in X well. A bow tie diagram is created to visualize the possible path of hazard and consequences. The risk assessment is then carried out and shows that the well can be operated under several evaluations with squeeze cementing being the right repair solution to solve the well integrity issue. The economic analysis further confirms squeeze cementing as a cost-effective repair solution, allowing the well to resume production.