Reverse Circulation Sand Washer

Abstract

The invention relates to a borehole operation tool, and specifically relates to a reverse circulation sand washing device. The reverse circulation sand washing device comprises a barrel; during sand washing, a sand washing solution passing through the middle of the barrel and the sand washing device is used for impacting the barrel so as to form a sand mixing solution; the sand mixing solution enters into a sand washing passage under the guide of a guide plate; a part of the sand mixing solution in the sand washing passage directly passes through a first filter so as to enter into a sand washing pipe column, and the part of the sand mixing solution is used for taking away tiny impurities; the other part of the sand mixing solution is used for taking large impurities into a crushing cavitythrough holes in a partition board; large sand enters into the crushing cavity along the radial direction of the barrel and collides with crushing teeth inside the crushing cavity; after the tiny impurities are formed by crushing the large sand, the small impurities enter into the sand washing pipe column through a second filter, so that the large impurities inside the sand mixing solution are crushed through the crushing cavity; and therefore, the sand washing device is avoided from being blocked by the impurities, repeated cleaning of the sand washing device is avoided, and the sand washingefficiency is improved.

Description

technical field [0001] The invention relates to a downhole operation tool, in particular to a reverse circulation sand flusher. Background technique [0002] In the process of oil and gas development, horizontal wells are used more and more. In the daily production process, the sand production of horizontal wells seriously affects the production efficiency of oil and gas wells. Especially after the horizontal wells have undergone multi-stage fracturing and acidizing measures, the sand production in the formation is becoming more and more serious. , therefore, sand washing in the horizontal section of the horizontal well is a technical problem that plagues the workover of the horizontal well. [0003] At present, the main problems in the sand washing process of horizontal wells are manifested in two aspects: one is that the sand bed is easy to form in the horizontal section during the sand washing process, and the sand-carrying ability of the deflection section of the horizon...

AI Technical Summary

Problems solved by technology

[0003] At present, the main problems in the sand washing process of horizontal wells are manifested in two aspects: one is that the sand bed is easy to form in the horizontal section during the sand washing process, and the sand-carrying ability of the deflection section of the horizontal well is weak, so that the sand and gravel cannot completely follow the washing process during sand washing. The sand fluid returns to the ground; second, after the horizontal well undergoes multi-stage fracturing, the fracturing sand and fracturing fluid are deposited at the bottom of the well, forming a cemented block. When washing sand with conventional sand washing process, when large cemented blocks or cuttings return to the wellhead, it is easy to block the sand washing pipeline, resulting in the failure of normal and continuous operation of the sand washing operation

[0004] For example, the Chinese invention patent application with the application number of 201610739965.1 discloses a reverse circulation sand flushing column, that is, a sand flusher. The column includes a joint and a cylinder, the joint communicates with the inner cavity of the cylinder, and the end connected There is a filter plate at the bottom, and a fishing basket is installed in the inner cavity of the barrel. When in use, use the sand washing string to lower the sand washing string into the wellbore, and then pass through the annular space between the wellbore and the sand washing string. The sand washing liquid is injected into the sand washing liquid, and the sand washing liquid impacts the sand particles at the bottom of the wellbore to form a sand mixing liquid. The sand mixing liquid enters the shell from the opening at the bottom of the shell, passes through the basket and the filter plate in turn, and returns to the ground through the sand washing pipe string. When the filter plate is used, the sand with a larger diameter is blocked by the filter plate and sinks into the basket, which ensures that the small sand will return to the ground and prevent the large sand or cuttings from blocking the pipe string. However, the large sand and cuttings in the wellbore will There are a lot of them, and these large sand grains and cuttings will quickly fill up the basket and block the sand washer during sand washing, so the sand washer can only be pulled out several times for cleaning, and the sand washing efficiency is very low

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