Wellhead special for electric submersible pump for geothermal well

Abstract

The invention relates to a special well mouth for an electric submersible pump for a geothermal well, which comprises a well mouth body and further comprises an upper flange positioned above the well mouth body, the upper flange is fixedly connected with the well mouth body, a first short section is arranged in the upper flange and is oppositely connected with the upper flange through a first connecting assembly, and the first short section is connected with the upper flange through a second connecting assembly. A second short section is further arranged in the upper flange, the second short section is relatively communicated with the upper flange through a second connecting assembly, and the first short section is located above the second short section and is relatively communicated with the second short section. The hanger has the advantage that the problem that the hanger cannot be detached due to corrosion, adhesion and other factors of a hanger wellhead is solved.

Description

Technical Field

[0001] This application relates to the field of supporting geothermal energy development, and in particular to a special wellhead for a submersible oil electric pump used in a geothermal well. Background Art

[0002] With the increasing scale of new energy development and utilization, the number of geothermal wells has been increasing year by year, and the demand for wellheads is also increasing. The existing special wellheads for submersible oil electric pumps in geothermal wells mainly consist of a wellhead body, a wellhead cover plate or a hanger. Referring to Figure 1 , the original hanger type structure is as shown in the figure. The hanger is prone to adhesion to the inner wall of the wellhead, which is inconvenient for hoisting.

[0003] The hanger is prone to adhesion to the inner wall of the wellhead, which is inconvenient for hoisting. The wellhead is not pressure-bearing, and the tensile strength of the welded wellhead is insufficient. It cannot meet the requirements of wellhead pressure-bearing sealing and well killing during the maintenance and shutdown of high-temperature geothermal wells. Summary of the Invention

[0004] In order to solve the problem that the hanger of the hanger wellhead cannot be disassembled due to factors such as rust and adhesion, this application provides a special wellhead for a submersible oil electric pump used in a geothermal well.

[0005] A special wellhead for a submersible oil electric pump used in a geothermal well provided by this application adopts the following technical solutions:

[0006] A special wellhead for a submersible oil electric pump used in a geothermal well includes a wellhead body, and also includes an upper flange located above the wellhead body. The upper flange is fixedly connected to the wellhead body. A first short section is arranged inside the upper flange. The first short section is relatively connected to the upper flange through a first connection assembly. A second short section is also arranged inside the upper flange. The second short section is relatively communicated with the upper flange through a second connection assembly. The first short section is located above the second short section and is relatively communicated.

[0007] Optionally, the first connection assembly includes a first internal thread opened on the inner side wall of the upper flange. A first external thread is opened on the outer side wall of the first short section opposite to the first internal thread. The upper flange and the first short section are relatively thread-connected through the first internal thread and the first external thread.

[0008] Optionally, after the upper flange and the first short section are screwed in place, the upper flange and the first short section are welded and fixed.

[0009] Optionally, the second connection assembly includes a second external thread opened on the outer side wall of the second short section. The second external thread is relatively thread-connected to the first internal thread.

[0010] Optionally, after the upper flange and the second short section are screwed in place, the upper flange and the second short section are welded and fixed.

[0011] Optionally, a tubing nipple is provided below the second short section, and the second short section and the tubing nipple are relatively communicated through a third connection assembly.

[0012] Optionally, the third connection assembly includes a first casing collar fixed on the outer side of the second short section. The bottom end of the first casing collar extends out from the bottom wall of the second short section, and the inner side wall of the first casing collar is fixedly connected to the tubing nipple.

[0013] Optionally, multiple tubing nipples are provided below the second short section. The second short section is connected to the uppermost tubing nipple through a first casing collar, and the multiple tubing nipples are connected through a fourth connection assembly.

[0014] Optionally, the fourth connection assembly includes a second casing collar fixed on the outer side wall of the tubing nipple located above adjacent to it. A reducing joint is fixedly connected to the outer side wall of the tubing nipple located below relative to the outer side wall of the second casing collar, and the reducing joint is fixedly connected to the second casing collar.

[0015] In summary, the present application includes at least one of the following beneficial technical effects:

[0016] For the suspended wellhead flange of the present application, the hanger is cancelled, solving the problem that the hanger at the wellhead cannot be disassembled due to factors such as rust and adhesion. The upper part of the flange also adopts threaded connection, so there is no need to disassemble the lifting nipple during operation, facilitating tripping operations and reducing labor intensity; the sealing method between the flanges is changed from a wire-wound gasket to a steel ring seal, solving the pressure-bearing problem during wellhead backflow, well killing and workover operations, and solving the problem that the gasket is a consumable part and needs to be replaced every time during wellhead disassembly. Description of the Drawings

[0017] Figure 1 is a prior art reference diagram in the background art.

[0018] Figure 2 is an overall structural schematic diagram of a special wellhead for a submersible electric pump in a geothermal well in the present application.

[0019] Description of the reference numerals: 1, wellhead body; 2, upper flange; 3, bottom flange; 4, first short section; 5, second short section; 6, tubing nipple; 7, first casing collar; 8, second casing collar; 9, reducing joint. Detailed Embodiments

[0020] In order to more clearly understand the above objects, features, and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0021] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0022] The following is a further detailed description of the present application in conjunction with the attached Figure 2 drawings.

[0023] An embodiment of the present application discloses a special wellhead for a submersible electric pump used in a geothermal well. Referring to Figure 2 , a special wellhead for a submersible electric pump used in a geothermal well includes a wellhead body 1. A top flange 2 is fixedly connected above the wellhead body 1, and the top flange 2 and the wellhead body 1 are relatively fixedly connected by bolts. A bottom flange 3 is fixedly connected below the wellhead body 1, and the bottom flange 3 and the wellhead body 1 are relatively fixedly connected by bolts.

[0024] A first short section 4 is coaxially arranged inside the top flange 2. An external thread is provided on the outer sidewall of the first short section 4, and an internal thread is provided inside the top flange 2 at a position corresponding to the external thread. By inserting the first short section 4 into the top flange 2, the internal thread and the external thread are threadedly connected to each other, and thus the first short section 4 is installed inside the top flange 2. And the bottom wall of the first short section 4 is higher than the bottom wall at the connection position of the top flange 2. After the top flange 2 and the first short section 4 are threadedly connected in place, the top flange 2 and the first short section 4 are relatively fixedly connected by welding.

[0025] A second short section 5 is arranged below the first short section 4. The second short section 5 is coaxially arranged with and abuts against the first short section 4, and the first short section 4 and the second short section 5 are relatively communicated. An external thread is provided on the outer sidewall of the second short section 5. When the second short section 5 is installed inside the top flange 2, the top wall of the second short section 5 abuts against the bottom wall of the first short section 4, so that the first short section 4 and the second short section 5 are relatively communicated. The external thread on the outer sidewall of the second short section 5 is threadedly connected and fixed to the internal thread of the top flange 2. After the top flange 2 and the second short section 5 are threadedly connected in place, the top flange 2 and the second short section 5 are relatively fixedly connected by welding.

[0026] Below the second short section 5, there are multiple tubing short sections 6 arranged in sequence. The multiple tubing short sections 6 are connected to each other in turn, and the tubing short section 6 at the top is oppositely connected and communicatively connected to the second short section 5. At the bottom end of the second short section 5, there is a first casing coupling 7. The first casing coupling 7 is located on the outer wall of the second short section 5, and the first casing coupling 7 is fixedly connected to the outer wall of the second short section 5 relatively.

[0027] Between two adjacent tubing short sections 6, there is a second casing coupling 8. The second casing coupling 8 is located on the outer wall of the upper tubing short section among the two adjacent tubing short sections 6, and the second casing coupling 8 is fixedly connected to the tubing short section 6.

[0028] On the outer wall of the lower tubing short section 6 among two adjacent tubing short sections 6, there is a reducer sub 9 fixedly connected. The top end of the reducer sub 9 extends into the interior of the second casing coupling 8, and the reducer sub 9 is fixedly connected to the second casing coupling 8. Through the second casing coupling 8 and the reducer sub 9, two adjacent tubing short sections 6 are fixedly connected relatively and communicatively connected relatively.

[0029] In the present invention, the term "multiple" means at least two or more than two, unless otherwise clearly defined. Terms such as "installed", "connected", "joined", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "joined" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In the description of this specification, the description of terms such as "one embodiment", "some embodiments", "specific embodiments" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

Claims

1. A special wellhead for a submersible oil electric pump used in a geothermal well, including a wellhead body (1). Characterized in that: It further includes an upper flange (2) located above the wellhead body (1). The upper flange (2) is fixedly connected to the wellhead body (1). A first short section (4) is arranged inside the upper flange (2). The first short section (4) is relatively connected to the upper flange (2) through a first connection component. A second short section (5) is also arranged inside the upper flange (2). The second short section (5) is relatively communicated with the upper flange (2) through a second connection component. The first short section (4) is located above the second short section (5) and is relatively communicated.

2. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 1. Characterized in that: The first connection component includes a first internal thread opened on the inner side wall of the upper flange (2). A first external thread is opened on the outer side wall of the first short section (4) opposite to the first internal thread. The upper flange (2) and the first short section (4) are relatively threadedly connected through the first internal thread and the first external thread.

3. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 2. Characterized in that: After the upper flange (2) and the first short section (4) are screwed in place, the upper flange (2) and the first short section (4) are welded and fixed.

4. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 2. Characterized in that: The second connection component includes a second external thread opened on the outer side wall of the second short section (5). The second external thread is relatively threadedly connected with the first internal thread.

5. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 4. Characterized in that: After the upper flange (2) and the second short section (5) are screwed in place, the upper flange (2) and the second short section (5) are welded and fixed.

6. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 1. Characterized in that: An oil pipe short section (6) is arranged below the second short section (5). The second short section (5) and the oil pipe short section (6) are relatively communicated through a third connection component.

7. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 6. Characterized in that: The third connection component includes a first casing coupling (7) fixed on the outer side of the second short section (5). The bottom end of the first casing coupling (7) extends out from the bottom wall of the second short section (5). The inner side wall of the first casing coupling (7) is fixedly connected to the oil pipe short section (6).

8. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 7. Characterized in that: Multiple oil pipe short sections (6) are arranged below the second short section (5). The second short section (5) and the uppermost oil pipe short section (6) are connected through a first casing coupling (7). The multiple oil pipe short sections (6) are connected through a fourth connection component.

9. The special wellhead for a submersible oil electric pump used in a geothermal well according to claim 8. Characterized in that: The fourth connection component includes a second casing collar (8) fixed to the outer wall of the adjacent upper tubing nipple (6), and a reducer sub (9) is fixedly connected to the outer wall of the lower tubing nipple (6) relative to the outer wall of the second casing collar (8), and the reducer sub (9) is fixedly connected to the second casing collar (8).

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