Pipe column and method used for layered chemical sand prevention

Abstract

The invention discloses a pipe column and a method used for layered chemical sand prevention. The pipe column comprises an upper layer filling assembly, an interlayer packer and a lower layer filling assembly which are connected in sequence from top to bottom; the upper end of the upper layer filling assembly is connected with an upper connector; the lower end of the lower layer filling assembly is connected with a lower connector; the upper layer filling assembly comprises an upper inner sliding sleeve and an upper outer sliding sleeve which are arranged in an internal-external sleeving mode; the lower end of the upper inner sliding sleeve is connected with an upper inner pressure spring; the upper end of the upper outer sliding sleeve is connected with an upper outer pressure spring; and an upper layer filling channel is formed between the upper inner sliding sleeve and the upper outer sliding sleeve. The lower layer filling assembly comprises a lower inner pipe and a lower outer sliding sleeve which are arranged in an internal-external sleeving mode; the lower end of the lower outer sliding sleeve is connected with a lower outer pressure spring; and a lower layer filling channel is formed between the lower inner pipe and the lower outer sliding sleeve. Layered sand consolidating agent injection of the immovable pipe column can be achieved, and the immovable pipe column can completely conduct reverse well washing at any time according to the needs, so that a sand consolidating agent is prevented from being regurgitated and solidified in the well.

Description

technical field [0001] The invention relates to sand control technology in oil field development, in particular to a pipe string and method which can be used for layered chemical sand control. Background technique [0002] The chemical sand control technology achieves the purpose of sand control by extruding sand-consolidating agent or coating proppant around the wellbore and consolidating in the near-wellbore zone at the bottom of the well to form an artificial well wall with a certain strength and permeability. For heterogeneous multi-layer reservoirs, it is difficult to realize the uniform transformation of each small layer in one general chemical sand control, and the effect of chemical sand control is not ideal. The existing layered sand control string has problems such as lifting and lowering the string to achieve layered injection during construction, and backwashing cannot be achieved without moving the string, which easily causes problems such as sand consolidation ...

AI Technical Summary

Problems solved by technology

For heterogeneous multi-layer reservoirs, it is difficult to realize the uniform transformation of each small layer in one general chemical sand control, and the effect of chemical sand control is not ideal

The existing layered sand control string has problems such as lifting and lowering the string to achieve layered injection during construction, and backwashing cannot be achieved without moving the string, which easily causes problems such as sand consolidation agent vomiting and consolidation in the wellbore , there are potential safety hazards, affecting the effect of chemical sand control

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