Treatment Measures of Quality Defects and Fractured Shaft Wellbore

The defects, cracks, and leakage of the shaft wellbore in Jining No.2 Coal Mine seriously threaten the safety of wellbore operators and equipment. The investigation, field test and water quality were used to show that the poor quality control of concrete pouring in the well wall and the water outlet of the well wall are the main reasons for the defect and fracture of the well wall. In this paper, the overall treatment plan of “leakage point chemical grouting sealing + defect area anchor net injection repair + wall surface silane impregnating corrosion” is developed. At present, the well wall has been repaired for nearly a year, and no new ruptures or leakage occurred. The experience can be used for similar projects.