Practice and Analysis of Plugging Horizontal Wells in the Chang-7 Section of the Dingbian Qingyang Area of the Ordos Basin

Abstract

Lost circulation can cause formation pollution and pressure imbalance, leading to various accidents in drilling engineering. It is necessary to have clarify the mechanism of drilling fluid leakage during the drilling process and the nature and condition of the leakage Analyze the different types of leakage in the Chang7 section of typical leakage wells in the Dingbian and Qingyang areas of the Yishan Slope in the Ordos Basin of Changqing Oilfield The research results indicate that: Permeable leakage is Leakage type with low leakage volume and low leakage rate, Plugging while drilling can be used until completion of the well.Large loss of reactivity requires multiple pumps of a large amount of plugging slurry to stop the leak, the required plugging slurry equivalent is closeLeakage caused by improper cementing due to engineering factors cannot be stopped by pumping the plugging slurry, This type of leakage situation requires cementing to achieve the goal of preventing leakage, And this kind of leakage will occur repeatedly. The leakage situation will evolve from initial permeable leakage to large-scale leakage The research results indicate the basic conditions for the occurrence of well leakage, combined with specific measures for plugging, Experience in providing leakage prevention and plugging techniques.