Study on wellbore annular sealing technology based on the influence of fracturing operation in low permeability oilfield

Abstract

At present, the fracturing technology has been very mature and is widely used in oil and gas field production operation. However, the fracturing operation will cause periodic changes in wellbore internal pressure and generate alternating stress. Due to the material factors of casing and cement sheath, the deformation of the two is inconsistent after stress, and then the damage of cement sheath and the failure of wellbore annulus seal occur. After water injection development, it is easy to produce channeling risk, so the performance of cement sheath is crucial. In view of this problem, through the theoretical analysis, experimental analysis and organic combination analysis of wellbore annulus cement ring sealing, the critical failure threshold of wellbore annulus cement ring under fracturing operation is given, which provides certain guidance for improving wellbore annulus sealing and reducing the risk of channeling after fracturing operation in the future.

Keywords

• fracturing operation
• cement ring for borehole
• alternating stress
• sealability