Simple repair type water injection well packer

Abstract

The invention relates to the technical field of oil and gas field mining equipment, and discloses a simple repair type water injection well packer. The packer comprises a central pipe, the upper end of the central pipe is provided with an upper joint, the lower end of the upper joint is provided with a sealing head, and the central pipe is movably sleeved with a sliding pipe located below the upper joint. The water injection pressure of the upper layer is preferentially applied to upper piston colloid to push the upper piston colloid to move downwards, the upper piston colloid pushes an upperpressing piece to move downwards, an extrusion head moves towards the interior of a special rubber cylinder, the special rubber cylinder is spread and radially deformed, the acting force between the special rubber cylinder and the inner wall of a casing pipe is increased, so that the resistance to the downward movement of the special rubber cylinder is increased, the extrusion force of the specialrubber cylinder to an ordinary rubber cylinder is reduced accordingly so that the ordinary rubber cylinder cannot slide in the casing pipe, the purpose that the acting force between the special rubber cylinder and the casing pipe is increased along with the increase of the water injection pressure of the upper layer is achieved, the movement difficulty of the packer is improved, and the probability of sealing failures is reduced.

Description

technical field [0001] The invention relates to the technical field of oil and gas field exploitation equipment, in particular to a simple and repairable water injection well packer. Background technique [0002] In the process of oil field exploitation, it is necessary to inject a large amount of water into the oil reservoir through a special water injection well to maintain or restore the pressure of the oil layer, so that the oil reservoir has a strong driving force, so as to improve the production speed and recovery rate of the oil reservoir, usually in The inner wall of the oil injection well is sealed with a casing, and the wellhead is equipped with a control device and a string suspension device. A string is installed at the bottom of the string suspension device, and a packer is installed at the corresponding part of the string. The annular space between the pipe strings is sealed to realize layered water injection. The existing packer is mainly composed of upper and...

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Problems solved by technology

[0003] 1. After the packer is seated, the force between the rubber sleeve and the inner wall of the casing is fixed and cannot increase with the increase of the upper layer water injection pressure. During the layered water injection process, the upper layer water injection pressure and the lower layer water injection pressure exist. Pressure difference, when the water injection pressure of the upper layer is higher than the water injection pressure of the lower layer, the packer receives a downward thrust, which is greater than the sum of the force between the slips and the inner wall of the casing and the force between the rubber sleeve and the inner wall of the casing At this time, the packer moves down and the pipe string is stretched. When the well is shut down frequently, the pipe string frequently wriggles under the force, causing abnormal deformation of the rubber sleeve and causing pack failure.

[0004] 2. After the packer is seated, the force between the slips and the inner wall of the casing is fixed and cannot increase with the increase of the water injection pressure of the lower layer. When the water injection pressure of the upper layer is lower than the water injection pressure of the lower layer, the packer will be affected. Upward thrust, when the thrust is greater than the sum of the force between the slips and the inner wall of the casing and the force between the rubber sleeve and the inner wall of the casing, the packer moves upwards, causing the pipe string to produce the Hooke effect, and the helical bending shortens , the rubber tube is abnormally deformed, resulting in failure of the seal

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