WELL COMPLETION METHOD Russian patent published in 2019 - IPC E21B43/114 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used in completion of wells. At well completion, drilling is performed with drilling of productive formation, lowering of production string, cementing of annulus space, perforation, treatment with acid and swabbing. During perforation lowering into the production string the assembly from the tubing string with piercing action perforator, performing perforation on process water with piercing perforator of production string and cement in annular space in interval of productive formation, after each actuation of perforator through perforator and formed perforation holes caverns in productive formation are washed in process water in amount of 2.5–3.5 m³ per 1 perforation at pressure 15–16 MPa with flow rate of 3.5–4 l/s. During treatment of the bed with acid, stepped acid treatment of the perforation interval is carried out with acid pumping and organization of acid baths under pressure with process water with stepped pressure increase at each stage until well injection capacity is not less than 0.5 l/s at pressure of 3–5 MPa. Swabbing is carried out in three stages with intensive extraction in amount of 0.5 m³ for 20–30 minutes at first and second stages and low-intensity extraction in volume of 0.5 m³ 45–60 minutes at the third stage. Process water used is water with density which provides back pressure to the formation, which includes a surfactant in amount of 0.1–0.3 wt% and a neutraliser of hydrogen sulphide of 0.08–0.12 wt%.

EFFECT: technical result is reduced risk of water flooding.

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