Hydraulic Shaping Technology of Deformed Casing after Fracturing in Horizontal Shale Oil Wells

Shale oil reservoirs need large-scale volume fracturing to obtain industrial oil flow. However, volume fracturing with a large fluid amount and large displacement is easy to cause casing deformation and borehole shrinkage, and it is hard to run fracturing and production tools into the well section below casing deformation. Conventional hydraulic shaping technologies have shortcomings such as poor repair ability, easy ball drop, and short validity period and thus fail to meet the technological requirements. In view of these problems, a series of hydraulic casing expansion tools were designed, such as expandable casing swage. Through laboratory tests, the casing expansion technology was perfected, and the hydraulic shaping technology of the deformed casing after fracturing in horizontal shale oil wells was formed. Field tests in Cangdong Sag show that the technology has a long validity period and can successfully solve the casing deformation problem in shale oil development, and it can restore the energy of the bottom well section by coiled tubing drilling out the multi-stage fracturing bridge plug (sweeping plug) when put into production.