Research On Mechanism And Theoretics Model Of Casing Damage In Water Injection Wells

With the progressing of the oil field development and changing of exploring program, due to various geological, engineering and managing conditions, the working conditions of oil, gas, and water injection wells gets worse or even damaged. As a result, the wells can not work normally and affects the steady production of oilfield. Casing damage is usually started at the water injection wells, whose damage proportion is much higher than that of oil wells, and then the oil wells. Because of all above, understanding the mechanism and factors relates to casing damage in water injection wells, finding out casing damage precautions fits well site will absolutely have significant economic value for the development of oil and gas reservoir. By reading enough documents and papers, along with producing practice of Gudao oilfield, the author analyzed the various causes of casing damage, using multi-professional and multi-subjects methods, introducing statistics of spot casing damage, theoretical analysis and computation methods, thoroughly and systematically study the mechanism of casing damage, put forward the mechanical model of casing damage. The main researches and computation of this paper focus on: earth stress, breakdown pressure, the relation between casing failure and injection pressure, mechanical model of casing damage, the corrosion rate of casing damage in water injection wells.