Preset plugging device for steam injection tubular column

Abstract

The utility model discloses a preset plugging device for a steam injection tubular column, and belongs to the technical field of oil production engineering. According to the technical scheme, the device comprises a preset working barrel arranged in the steam injection tubular column and a plugging sealing body which is anchored and sealed with the preset working barrel after entering the preset working barrel. The utility model has the beneficial effects that the plugging in the high-temperature pipe can be realized, well washing and killing are not needed before operation, fluid entering the well is reduced, an oil layer is protected, and the risk of high-temperature operation is reduced.

Description

Technical Field

[0001] The utility model relates to a pre-placed plugging device for a steam injection pipe column, belonging to the technical field of oil production engineering. Background Art

[0002] Heavy oil development techniques primarily include steam flooding, SAGD, fire flooding, and steam stimulation. Steam stimulation accounts for a significant portion of this, and well-washing and killing operations are typically employed. As oilfield recovery increases, reservoir pressure drops significantly, leading to significant kill fluid losses and sudden well control safety hazards such as dissolved gas migration and interwell steam channeling. This also prolongs post-operation fluid drainage time and, in severe cases, can block the oil formation. High-temperature in-line plugging, a core technology for thermal well snubbing, is currently immature and presents significant challenges in high-temperature sealing.

[0003] CN115478823A discloses a pipe string for integrated steam injection and production operations, which uses a valve body assembly with a torsion spring to seal the central pipe port. The sealing area is a replacement surface and the sealing performance cannot be guaranteed. Utility Model Content

[0004] In view of the defects of the prior art, the utility model provides a pre-set plugging device for a steam injection pipe column which can realize plugging in a high-temperature pipe.

[0005] The technical solution of the utility model is: a steam injection pipe column pre-sealing device, comprising a pre-sealing working cylinder arranged in the steam injection pipe column, and a sealing body which is anchored and sealed with the pre-sealing working cylinder after entering the pre-sealing working cylinder.

[0006] The preset working cylinder is located at the bottom end of the steam injection pipe column.

[0007] The preset working cylinder is provided with an anchoring groove, a limiting step and a sealing surface in sequence from top to bottom.

[0008] The blocking seal comprises a main body, the bottom of which is connected to the seal, an anchor unit which cooperates with the anchor slot is movably provided on the main body, and a sealing unit which cooperates with the sealing surface is provided on the outer periphery of the seal.

[0009] A weighting rod is provided at the bottom of the sealing body, and an air compression buffer hole is opened at the bottom end of the weighting rod.

[0010] The weighting rod is threadedly connected to the sealing body.

[0011] The main body and the sealing body are threadedly connected.

[0012] The anchoring unit includes locking blocks symmetrically arranged on both sides of the main body. The locking blocks are engaged with the anchoring slots. The locking blocks are rotatably connected to the main body through a pin shaft. The end of the locking block is connected to a torsion spring, and the other end of the torsion spring is connected to the main body.

[0013] The sealing unit includes a rubber cylinder and a rubber cylinder ring which are sleeved on the sealing body. The rubber cylinder cooperates with the sealing surface for sealing. The rubber cylinder ring is located on both sides of the rubber cylinder. A limiting ring is fixed on the sealing body on the side of the rubber cylinder ring. A limiting sleeve for limiting the rubber cylinder ring is fixed on the main body.

[0014] There are two rubber cylinders and three rubber cylinder rings, and the three rubber cylinder rings are spaced apart from the two rubber cylinders.

[0015] The beneficial effects of the utility model are as follows:

[0016] (1) The utility model provides a pre-set plugging device for a steam injection pipe column, which can achieve in-pipe plugging of a high-temperature well.

[0017] (2) The pre-set plugging device achieves plugging inside the pipe by delivering the plugging sealant to the wellhead, which is simple and convenient to operate.

[0018] (3) Anchoring and sealing are reliable, and the sealing effect is good. The device forms a seal by cooperating with the pre-set working cylinder and the sealing body, and the structure is reliable.

[0019] (4) The sealing section adopts high temperature resistant sealing rubber tube, which has good high temperature resistance effect.

[0020] By using the plugging device described in the utility model, high-temperature pipe internal plugging can be achieved, and there is no need to wash and pressurize the well before operation, which reduces the fluid entering the well, protects the oil layer, and reduces the risk of high-temperature operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural diagram of the sealing body;

[0022] Figure 2 This is a structural diagram of the preset working cylinder;

[0023] Figure 3 This is the application view of the utility model;

[0024] Figure 4 Pre-set plugging flow chart for steam injection string.

[0025] The reference numerals in the figure are as follows: 1.1, anchoring slot, 1.2, limiting step, 1.3, sealing surface, 2.1, main body, 2.2, sealing body, 2.3, weighting rod, 2.4, locking block, 2.5, pin shaft, 2.6, torsion spring, 2.7, rubber cylinder, 2.8, rubber cylinder ring, 2.9, limiting ring, 2.10, limiting sleeve. DETAILED DESCRIPTION

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below in combination with the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] Next, the present invention is described in detail with reference to schematic diagrams. For ease of illustration, cross-sectional views of device structures may be partially enlarged and not to scale when describing the embodiments of the present invention. Furthermore, the schematic diagrams are merely illustrative and should not limit the scope of protection of the present invention. Furthermore, in actual production, three-dimensional dimensions, including length, width, and depth, should be included.

[0030] Example 1

[0031] A steam injection string pre-sealing device comprises a pre-sealing mandrel disposed at the bottom of the steam injection string and a sealing body that is anchored and sealed with the pre-sealing mandrel after entering the pre-sealing mandrel. The pre-sealing mandrel is provided with an anchoring groove 1.1, a limiting step 1.2, and a sealing surface 1.3 in sequence from top to bottom.

[0032] The plugging seal comprises a main body 2.1, the bottom of which is connected to a sealing body 2.2. An anchor unit movably mounted on the main body 2.1 engages with the anchoring slot 1.1. A sealing unit is disposed on the periphery of the sealing body 2.2, which engages with the sealing surface 1.3. The upper and lower ends of the sealing body 2.2 are threadedly connected to the main body 2.1 and the weighting rod 2.3, respectively. The weighting rod 2.3 has an air compression buffer hole at its bottom, which is sealed at the top. During the drop of the plugging seal from the wellhead, the air in the air compression buffer hole is compressed, providing a buffering effect and preventing the sealing rubber sleeve from being dislodged by water erosion.

[0033] The anchoring unit includes locking blocks 2.4 symmetrically positioned on either side of the main body 2.1. These lock blocks 2.4 engage with the anchoring slots 1.1 and are rotationally connected to the main body 2.1 via a pin 2.5. The ends of the lock blocks 2.4 are connected to a torsion spring 2.6, the other end of which is connected to the main body 2.1. Under the elastic force of the torsion spring 2.6, the lock blocks 2.4 tend to rotate outward from the main body 2.1. When the lock blocks 2.4 move downward to the anchoring slots 1.1, the elastic force of the torsion spring 2.6 forces the ends of the lock blocks 2.4 into the anchoring slots 1.1, locking them together. This prevents the main body 2.1 from moving upward relative to the pre-set mandrel, ensuring structural stability and reliability under high pressure downhole.

[0034] The sealing unit comprises a rubber sleeve 2.7 and a rubber sleeve ring 2.8, which are mounted on the sealing body 2.2. The rubber sleeve 2.7 seals against the sealing surface 1.3. The rubber sleeve rings 2.8 are located on either side of the rubber sleeve 2.7. Limiting rings 2.9 are fixed to the sealing body 2.2 on either side of the rubber sleeve rings 2.8. A limiting sleeve 2.10 is fixed to the main body 2.1 to limit the position of the rubber sleeve rings 2.8. The rubber sleeve 2.7 is a high-temperature resistant sealing rubber sleeve. There are two rubber sleeves 2.7 and three rubber sleeve rings 2.8, which are spaced apart from the two rubber sleeves 2.7. The outer surface of the high-temperature resistant sealing rubber sleeve is in close contact with the sealing surface 1.3, ensuring a good seal even in high-temperature environments.

[0035] Example 2

[0036] like Figure 4 As shown in the figure, for the pre-installed plugging device of the steam injection column, the specific operation steps are as follows:

[0037] 1. Before lowering the pre-installed plugging device into the well, check whether it functions normally and whether the threaded connection is reliable;

[0038] 2. The pre-set working cylinder is connected to the lower end of the steam injection string and lowered into the designed depth along with the steam injection string;

[0039] 3. After the steam injection is completed, when the steam injection string needs to be lifted, the plugging seal is delivered from the wellhead, and the seal enters the working cylinder under the gravity of the weighted rod;

[0040] 4. Observe that there is no pressure at the wellhead, which proves that the plugging and sealing body has been delivered to the right place and has been anchored and sealed with the working cylinder;

[0041] 5. Combined with pressure operation, the pressure at the wellhead and inside the pipe can be controlled. The pre-set plugging tool is pulled out with the pipe string, the plugging seal is unsealed and removed, and the integrity of the high-temperature rubber sleeve is checked.

[0042] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A steam injection column pre-plugging device, characterized in that: It includes a preset mandrel arranged in the steam injection pipe column, and a plugging and sealing body which is anchored and sealed with the preset mandrel after entering the preset mandrel; The preset working cylinder is provided with an anchoring groove (1.1), a limiting step (1.2) and a sealing surface (1.3) in sequence from top to bottom; The blocking seal comprises a main body (2.1), the bottom of the main body (2.1) is connected to a sealing body (2.2), an anchoring unit that cooperates with the anchoring slot (1.1) is movably provided on the main body (2.1), and a sealing unit that cooperates with the sealing surface (1.3) is provided on the outer periphery of the sealing body (2.2).

2. The steam injection column pre-plugging device according to claim 1, characterized in that: The preset working cylinder is located at the bottom end of the steam injection pipe column.

3. The steam injection column pre-plugging device according to claim 1, characterized in that: A weighting rod (2.3) is provided at the bottom of the sealing body (2.2), and an air compression buffer hole is opened at the bottom end of the weighting rod 2.

3.

4. The steam injection column pre-plugging device according to claim 3, characterized in that: The weighting rod (2.3) is threadedly connected to the sealing body (2.2).

5. The steam injection column pre-plugging device according to claim 1, characterized in that: The main body (2.1) and the sealing body (2.2) are threadedly connected.

6. The steam injection column pre-plugging device according to claim 1, characterized in that: The anchoring unit comprises locking blocks (2.4) symmetrically arranged on both sides of the main body (2.1); the locking blocks (2.4) are engaged with the anchoring slots (1.1); the locking blocks (2.4) are rotatably connected to the main body (2.1) via a pin shaft (2.5); an end of the locking block (2.4) is connected to a torsion spring (2.6); and the other end of the torsion spring (2.6) is connected to the main body (2.1).

7. The steam injection column pre-plugging device according to claim 1, characterized in that: The sealing unit comprises a rubber cylinder (2.7) and a rubber cylinder ring (2.8) sleeved on the sealing body (2.2); the rubber cylinder (2.7) cooperates with the sealing surface (1.3) for sealing; the rubber cylinder ring (2.8) is located on both sides of the rubber cylinder (2.7); a limiting ring (2.9) is fixed on the sealing body (2.2) on the side of the rubber cylinder ring (2.8); and a limiting sleeve (2.10) for limiting the rubber cylinder ring (2.8) is fixed on the main body (2.1).

8. The steam injection column pre-plugging device according to claim 7, characterized in that: There are two rubber cylinders (2.7) and three rubber cylinder rings (2.8), and the three rubber cylinder rings (2.8) are spaced apart from the two rubber cylinders (2.7).

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