Fracturing and completion integrated method adopting coiled tubing and production tubing combined tubing string

Abstract

The invention belongs to the technical field of oil and gas field fracturing, particularly relates to a fracturing and completion integrated method adopting a coiled tubing and production tubing combined tubing string. The method specially comprises steps as follows: 1) placing the combined tubing string down to a shaft; 2) setting a first section; 3) performing sand blasting perforation on the first section; 4) fracturing the first layer section; 5) injecting a fracturing fluid; 6) lifting up a fracturing tubular column to a designed perforation position of a second section after the first section is fractured, and repeating Steps 2)-5) to finish the fracturing construction of all construction sections; 7) after construction, placing the fracturing tubular column at the bottom of an artificial well, and throwing steel balls from the wellhead to enable a hydraulic releasing tool to realize release; 8) draining the fluid and putting the oil and gas into production. With adoption of the method, after fracturing, the production tubular column can be placed one less time, so that damage to a reservoir is reduced while the working cycle is shortened.

Description

technical field [0001] The invention belongs to the technical field of fracturing in oil and gas fields, and in particular relates to an integrated method for fracturing and well completion with a combination of coiled tubing and production tubing. Background technique [0002] The hydraulic sandblasting fracturing technology integrates perforation and fracturing, and has become the main technology for developing low-permeability oil and gas fields. Combined with the characteristics of coiled tubing that can be dragged under pressure, it has the advantages of unlimited number of stimulated layers, and the wellbore remains open after fracturing. Incomparable advantages of conventional technology such as diameter. [0003] Among them, coiled tubing perforation, annular fracturing, and anchored mechanical packer isolation methods have the characteristics of reliable isolation, large fracturing displacement, and high construction efficiency, and are widely used. However, after ...

AI Technical Summary

Problems solved by technology

However, when the fracturing string is pulled out after fracturing in this process, on the one hand, there is a large construction risk; on the other hand, for low-pressure and low-production gas wells, hydrocarbon condensate or formation water will flow into the bottom of the well during the production process. Due to the poor liquid-carrying capacity of the large-diameter tubing (produced gas will not meet the requirement of continuous liquid-carrying due to the low flow rate), the liquid accumulation in the wellbore will continue to increase, and the bottom hole back pressure will continue to increase, sometimes even Gas wells are completely crushed and shut down, seriously polluting the fractured layers, causing damage to reservoirs, and directly affecting the production and recovery rate of gas wells

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