Study on the cause classification and prevention methods of casing damage

No. 5 Production Plant of Daqing Oil Field Daqing, Heilongjiang 163513, China

^* Corresponding author: 458116900@qq.com

Abstract

The casing damage wells in non oil layers are mainly distributed in the N2 and SI-SII oil shale interlayer, and the casing damage types are mainly deformation and dislocation. The main reason is that the injected water enters into the oil shale, the cementing quality is poor, and it is easy to form an invasion water area after invading along the channeling channel, which reduces the stability of the formation. Under the effect of geostress, the force generated by the formation sliding along the weak surface is directly applied to the casing, causing shear casing damage; The casing damage in the oil reservoir is mainly concentrated in SII1-5 layers, which is analyzed as a result of high pressure water injection and large difference in plane and interlayer pressure; The casing damage on the fault plane is mainly caused by slip caused by water softening on the fault plane and fault activity caused by excessive difference in pore pressure of oil layers on both sides of the fault. This paper expounds the measures taken in daily management from the aspect of casing damage prevention, which provides a basis for the prevention and control of casing damage wells in the future.