Horizontal well cementing anti-plug fluid and preparation method thereof

Abstract

The invention discloses cementing and anti-blockage fluid for horizontal wells and a method for manufacturing the cementing and anti-blockage fluid. The cementing and anti-blockage fluid comprises, by weight, 3-5% of low-polymerization-degree celluloses, 2-4% of filtrate loss reducers, 4-6% of sustained release treating agents, 0.5-1% of particle dispersing agents and the balance water. The cementing and anti-blockage fluid and the method have the advantages that the cementing and anti-blockage fluid mainly solves technical problems that cement slurry is retained in a casing after a single side of a rubber plug is abraded and the bottom of a well cannot be measured; the cementing and anti-blockage fluid is easy to prepared in a field and is good in flowing property and high in cement particle suspending and dispersing capacity; deposited cement can be stopped from blocking a channel in a casing; a construction procedure for drifting and drilling a plug by the aid of a small drilling tool can be omitted.

Description

technical field [0001] The invention relates to the technical field of oil field drilling and completion engineering, in particular to an anti-clogging fluid for horizontal well cementing used to prevent cement deposition from clogging channels during on-site construction of horizontal well cementing. Background technique [0002] With the in-depth development of low-efficiency oil and gas reservoirs, the recovery rate of vertical wells and directional wells can no longer meet the needs of society for energy. Horizontal well drilling has been widely used in major oil fields; Changqing Oilfield belongs to the above-mentioned "three low" oil and gas fields. With the continuous improvement of equipment and drilling technology, horizontal well drilling has shown a leapfrogging and increasing trend in recent years. Before 2010, the total number of horizontal wells developed in this block was less than 50. From 2010 to 2012, the number of horizontal wells has reached more than 300...

AI Technical Summary

Problems solved by technology

Before 2010, the total number of horizontal wells developed in this block was less than 50. From 2010 to 2012, the number of horizontal wells has reached more than 300, which has greatly improved the recovery rate of oil and gas; New technical problems, the horizontal well casing is bent and deformed, and when the cementing is completed, the dirty cement slurry remains in the casing and accumulates to block the channel, causing the logging to fail to measure to the bottom. Plug handling

[0004] 1. The rubber plug is severely worn during operation, and cement slurry channeling occurs;

[0005] 2. The force of the rubber plug is not uniform, resulting in unilateral displacement and retention of cement slurry;

[0006] 3. The quality of the rubber plug may be not wear-resistant, not pressure-resistant, and poor in temperature resistance, resulting in the cement slurry not being replaced cleanly

However, this technology cannot fundamentally solve the above problems, and there is still a technical problem that the cement slurry is retained in the casing after the rubber plug is unilaterally worn, causing the logging to fail to measure the bottom.

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