Research and Application on Countermeasures for Reducing the Termination Rate of Minor Repairs

During the oilfield development process, due to factors such as the increasing service time of tubing strings in oil and water wells, uneven cementing quality, and differences in geological structures, the casings of oil and water wells will inevitably suffer varying degrees of damage. These casing damage phenomena can cause casing deformation or sand accumulation inside the pipes. During operation, such casing damage or sand return is likely to lead to sticking of downhole pipe strings and failure to fish out complex fallen objects, resulting in the termination of minor repair operations and their conversion to major repair operations. This will prolong the shutdown time of individual wells and increase maintenance operation costs. To improve the success rate and efficiency of minor repair operations, reduce additional costs caused by the conversion from terminated minor repairs to major repairs, and lower the maintenance operation costs of oilfield development, a combination of technical and management methods was adopted in the research. Classification governance principles were formulated for different types of difficult wells in minor repairs, and corresponding technical processes and tools were applied for research. The results show that the application of relevant countermeasures has significantly improved the construction capacity of minor repairs, markedly increased the success rate of handling terminated wells, and obviously reduced the termination rate of minor repairs, providing strong support for the efficient advancement of oilfield development.