A detachable casing protection setting water injection string and structure optimization method

Abstract

Provided is removable casing protected and packers sealed a water injection pipe column, and belongs to the technical field of water injection pipe columns. The removable casing protected and packerssealed water injection pipe column comprises an oil pipe (9), and is characterized in that the oil pipe (9) is provided with a clamping device, the outer portion of the oil pipe (9) is sleeved with acasing (7), and through a plurality of clamping devices, between the casing (7) and the oil pipe (9), the oil pipe (9) is removably sleeved with a hydraulic anchor (1), packers, water distributors anda bottom ball. According to the removable casing protected and packers sealed water injection pipe column, other components outside the oil pipe are installed in a removable mode, clamping devices are arranged on the oil pipe for disassembly and assembly, through the clamping devices, the other components can be quickly installed and disassembled, and through the clamping devices, flexible adjustment of mounting parts with different sizes can be conducted, each structure can be assembled according to different size requirements, so that the application is improved, at the same time, an integral structure of the water injection pipe column can also be formed, fishing out and throwing a dead core are not needed, the field operation is simple; the removable casing protected and packers sealed water injection pipe column can adapt to a variety of working conditions, the adaptability is high, and then the work cost is reduced.

Description

technical field [0001] A detachable casing protection setting water injection pipe string and a structure optimization method belong to the technical field of water injection pipe strings. Background technique [0002] Oilfield water injection string plays a very important role in oilfield production, but the wear of the packer and the creep of the string are important problems that need to be solved urgently. In recent years, some newly proposed improvement schemes are gradually solving these problems, but the effect is not good. [0003] During the field application of conventional stuck-sealed layered water injection strings, it was found that, on the one hand, the string creep caused by downhole water injection pressure fluctuations and other causes easily damaged the rubber sleeve of the packer at the upper end of the casing string, thus reducing the sealing capacity. The airtightness of the packer prevents the normal water injection work and greatly reduces the servic...

AI Technical Summary

Problems solved by technology

In recent years, some newly proposed improvement schemes are gradually solving these problems, but the effect is not good

[0003] During the field application of conventional stuck-sealed layered water injection strings, it was found that, on the one hand, the string creep caused by downhole water injection pressure fluctuations and other causes easily damaged the rubber sleeve of the packer at the upper end of the casing string, thus reducing the sealing capacity. The airtightness of the packer prevents the normal water injection work and greatly reduces the service life of the pipe string; on the other hand, conventional water distribution tools need to go downhole with a dead core, but after the packer is pressed and set, It is necessary to remove the dead core to inject water, which makes the whole water injection process very cumbersome and cannot be carried out smoothly, and a lot of time is wasted; in addition, an integrated water injection string has appeared at present, but due to the packer The relatively fixed positions of components such as water distributors and hydraulic anchors make the device unable to cope with all water injection conditions, and the application value is not high

[0004] The instability and stress of the injection well string were analyzed and studied, and some improved measures were proposed, including the use of small diameter strings, etc., such as Chinese patents CN206158707U, CN206158709U and CN203756146U, etc., among them, CN206158707U records The technical solution is to improve the water injection effect by increasing the sealing. In essence, it is a method to improve the effect by increasing the amount. It only helps the sealing to a certain extent, but the structure is complicated and the cost is high.

[0005] The technical scheme recorded in CN206158709U is to increase a compensator, so that the pipe string has a certain improvement effect in the anti-creep, but the structure is more complicated, and the cost has a certain increase. Only relying on the compensator cannot cope with various working conditions, and the actual effect is not particularly obvious

[0006] The technical solution recorded in CN203756146U is to integrate the entire water injection string, thereby solving a series of effects caused by the peristalsis of the string at the root, but the mutual fixation between the parts makes the adaptability of the structure greatly reduced, and also Indirectly increases the cost of using

It can be seen that although the technical solutions in the prior art have improved the water injection string, they are all aimed at specific creep reasons, unable to adapt to various working conditions, complex in structure, and high in cost

However, these measures cannot improve the peristalsis of the pipe string, the sealing of the packer and the adaptation to the working conditions.

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