Investigation Of Formation Fluids Effect On Casing String Corrosion While Drilling

The casing of the well is the most important part of the process of drilling wells for crude oil becauseof its great importance, it is the spine of the continuity of the production processes in oil and gas wells.Previous research has led to the conclusion that failure due to the external wall of the production casingaccounts for the majority of failures in oil wells. The corrosion of iron (casing) types K-۵۵ and N-۸۰was examined in various fluid circumferences, such as salt water (SW), formation fluid (FF), sulfuricacid concentration ۱M (SA), and two types of drilling mud related to formation fluids drilling mudpolymer lime-based (MU۱) and (MU۲). It was determined that corrosion occurs more quickly in theacidic fluid circumference, and this is why the corrosion rate values indicate this. Then we investigatedthe effect of time on iron (casing) corrosion in each of the fluid circumferences studied. We observedthat corrosion rates decreased over time. The effect of pH on iron (casing) corrosion was alsoinvestigated. The highest corrosion rates were found in the acidic fluid circumference. In an acidic fluidsolution of (۱M) sulfuric acid, the effect of temperature on iron (casing) corrosion was investigated, andthe corrosion rates were observed to increase with the high temperature of the corrosive fluidcircumference.

Keywords:

Casing Corrosion Rate , Casing Grades , Loss Weight Method , Drilling Fluids , Formation Fluids , Sulfuric Acid , Formation Fluid Acidity