Fracturing method for preventing casing deformation and application thereof

Abstract

The invention relates to a novel fracturing method for preventing casing deformation, belongs to the field of oil exploitation, and is suitable for shale oil and gas reservoirs. The method adopts the integrated design technology of drilling, well completion and fracturing, the horizontal wellbore passing direction is optimized, the plane perforation technology is adopted, the type, formula, injection technological parameters and the like of pretreatment acid are reasonably optimized, the supercritical CO2 fracturing fluid is matched for rock breaking, and 70-140 mesh self-suspension propping agents and other technological technologies are applied in the whole process, so that casing fracturing deformation is prevented, and the fracturing crack transformation volume is fully increased. According to the method, the fracturing transformation effect is greatly improved, the optimization result can effectively guide fracturing construction, the transformation size is greatly increased, the construction effect is obviously improved, and therefore the maximum economic benefit is obtained.

Description

technical field [0001] The invention belongs to the field of petroleum exploitation, and in particular relates to a new method for preventing deformation of casings by deep shale gas fracturing. Background technique [0002] At present, deep shale gas fracturing technology is being applied more and more, but due to the substantial increase in burial depth, the three-dimensional stress also increases correspondingly, and the stress concentration effect caused by horizontal wellbore and perforation is obvious during drilling. The combination of the high construction pressure in the wellbore during the hydraulic fracturing construction and the pressure pulse effect generated in the variable displacement construction that is often used, etc., all aggravate the damage to the strength of the casing, and even cause casing deformation in severe cases The passive situation caused many negative impacts on the follow-up bridge plug perforation joint operation and post-press drilling pl...

AI Technical Summary

Problems solved by technology

However, when the fractures extend to a certain extent, due to the strong heterogeneity of shale, some fractures will always extend more fully, and because the length of a single cluster of perforations is long, the final number of fracture extensions may need to be appropriately increased. The extension displacement of each fracture is reduced, therefore, the width of the fracture is also reduced correspondingly, which may induce early sand plugging, resulting in a continuous and rapid rise in construction pressure, which is not conducive to the protection of casing