Research and Application of Casing Leakage Treatment Workover Technology

Research purpose and scope: With the continuous advancement of oilfield development, the interplay of factors such as formation stress changes, corrosion, and high-pressure water injection has led to frequent occurrences of casing leaks in oil and water wells. These leaks jeopardize wellbore integrity, pose safety hazards, and hinder development. This study aims to efficiently address casing leaks through technical means. Methods, steps and processes: To tackle the challenges of casing leak remediation, a comprehensive analysis of key parameters such as the production life of the wells, current casing conditions, and leak depths was conducted. The wells were systematically categorized, followed by the targeted application of three core technologies: shallow casing replacement, casing reinforcement, and cement plugging. These methods precisely address various types of casing leaks and eliminate potential hazards. Fracturing technology. Results, understanding and conclusion: To overcome the difficulties in casing leak remediation and eliminate safety risks, the three technologies of shallow casing replacement, casing reinforcement, and cement plugging were applied. A comprehensive assessment of factors such as the severity of safety hazards, oilfield development needs, and well intervention complexity was conducted, coupled with precise classification based on individual well conditions. For wells with short casing service life, cement plugging was used for rapid leak stoppage; shallow casing leaks were thoroughly resolved with shallow casing replacement; and deep casing leaks that were not suitable for replacement were efficiently repaired with casing reinforcement, ensuring the normal production of oil and water wells. Innovation points, technical contribution and significance: In the maintenance of oil and water wells, the three technologies of shallow casing replacement, casing reinforcement, and cement plugging have demonstrated significant effectiveness. They can quickly eliminate hazards, ensure the safe and stable production of oil and water wells, and promote the sustainable development of oilfields, making them highly valuable for widespread application. These technologies effectively and efficiently address existing safety hazards in oil and water wells, ensuring stable production and fostering the continuous and favorable development of oilfields, thus holding substantial promotion value.