Abstract:In the Shunbei block drilling work, there are many wells with complicate circulation loss in the Permian formation, such as large amount of leakage, second or multiple leakage. In some worse cases, it leads to collapse of the borehole and bit sticking, causing frequent down hole difficulties, bringing losses to the drilling project, and inhibiting the speed of exploration and development of the block. The down hole complex conditions exhibit mainly in the manner of leakage due to development of Permian igneous rock and strata fracture. In order to solve this problem, analysis of the complex Permian well leakage in the Shunbei area was carried out, and the Permian drilling difficulty in the area was analyzed in the light of the actual drilling situation in the Shunbei block and the characteristics of the Permian strata. This paper summarizes the concrete plugging-while-drilling measures and plugging schemes for leakage at different rates. Field results have proven that this comprehensive leak plugging strategy can effectively reduce complex leakage and improve the leak plugging efficiency.