Pressure self-balancing double-barrier blanking plug for high-pressure gas well under-pressure well completion

Abstract

The invention discloses a pressure self-balancing double-barrier blanking plug for high-pressure gas well under-pressure well completion, and relates to the field of oil-gas well under-pressure operation downhole tools. The blanking plug mainly comprises a positioning cylinder, an upper rupture disk and a lower rupture disk, wherein a limiting end surface for fixing the upper rupture disk and the lower rupture disk is arranged in the positioning cylinder; the upper rupture disk and the lower rupture disk are both of U-shaped structures; the convex directions of the U-shaped structures are downward; a one-way valve is fixedly arranged on the positioning cylinder; the one-way valve is positioned between the upper rupture disk and the lower rupture disk; and the one-way valve communicates with the interior of a pipeline above the upper rupture disk. According to the blanking plug, the upper rupture disk and the lower rupture disk form a double-barrier sealing structure, so that the reliability of under-pressure operation downhole plugging is improved, and the blanking plug is suitable for high-pressure gas well operation; and a one-way passage for connecting the upper space and the lower space of the upper rupture disk is established through the one-way valve, so that the self-balancing of the upper pressure and the lower pressure of the upper rupture disk is realized, and the problem that the upper rupture disk fails in advance due to screw thread leakage can be solved.

Description

technical field [0001] The invention relates to the field of downhole tools for oil and gas wells under pressure, in particular to a pressure self-balancing double-barrier plug for high-pressure gas well completion under pressure. Background technique [0002] In the process of oil and gas production, the snubbing operation has the characteristics of no snubbing and blowout, which can greatly shorten the operation cycle and save capital investment for well killing. The most important thing is that the snubbing operation can protect the production layer and maintain the pressure of the production layer. The long-term continuous exploitation of the oil field provides the conditions. During the completion operation of high-pressure gas wells under pressure, due to the light density, flammable and explosive physical properties of the gas, plugging devices are often used in the tubing operation to ensure that the inside of the tubing is blocked and the pressure is not released to...

AI Technical Summary

Problems solved by technology

The tool only relies on the concave rupture plug to seal, so the plugging effect is still unreliable

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