Horizontal well repeated fracturing device and method based on open-hole preset tubular column well completion

Abstract

The invention relates to a horizontal well repeated fracturing device and method based on open-hole preset tubular column well completion. Firstly, an original fracturing sliding sleeve ball seat in apreset pipe column is grinded and milled to achieve the full diameter of a well shaft and provide a passage for a repeated fracturing device to enter; impurities such as steel slag and the like remained in the grinded and milled ball seat on the sleeve wall are cleaned through two well passing procedures, and the resistance risk of a repeated fracturing device is reduced; because the sand blasting port in the sleeve is in an open state after the primary fracturing, the gap between an oil pipe and a tail pipe is blocked by an oil pipe packer, the tail pipe is blocked by a sealing piece, and the oil pipe packer and the sealing piece are respectively positioned at two sides of the same nozzle, the liquid outlet of the oil pipe is positioned in the sealed space, and after the packer is set and sealed, the repeated fracturing transformation is finished according to the pump injection procedure; and then the tool is released when the internal pressure difference and the external pressure difference are consistent, and the pipe column is lifted. The method achieves the purpose of repeated fracturing modification under the condition of open-hole prefabricated tubular column well completion, prolongs the service life of an oil well and increases the yield.

Description

technical field [0001] The invention relates to a horizontal well refracturing device and method based on open hole preset pipe string completion. Background technique [0002] At present, the staged fracturing technology of horizontal wells has become an important means for the development of tight and low-permeability oil and gas reservoirs. For different completion methods of horizontal wells, such as open hole prefabricated string or casing cementing, there are corresponding mature fracturing technologies. Among them, the open-hole packer staged fracturing process matched with the prefabricated string completion method, as shown in the attached figure 1 As shown, a three-stage wellbore structure is adopted, only the vertical section a is cemented, and the horizontal section b is not cemented. The liner 4, the packer 3 and the ball sliding sleeve 1 are combined in the horizontal section of the open hole, and the liner is used. 4. Suspension way to complete the well. Dur...

AI Technical Summary

Problems solved by technology

However, if the production condition of the horizontal well deteriorates and you want to refracture the horizontal section, due to the variable diameter of the ball seat of the sliding sleeve in the well, it is difficult to run conventional fracturing tools, which brings difficulties to the refracturing

[0004] The refracturing technology of horizontal wells in the prior art is generally used in cementing and completion horizontal wells, but the refracturing technology under the condition of open hole prefabricated string completion has not yet appeared

Images