Structure for improving pressure bearing strength of air cavity

Abstract

The utility model discloses a structure for improving the pressure-bearing strength of an air cavity. The structure comprises an air cavity outer cylinder; one end of the air cavity joint extends into and is fixed on the inner wall of the air cavity outer cylinder; the air cavity mandrel is arranged in the air cavity outer cylinder and the air cavity connector in the axial direction; the first supporting face is arranged on the air cavity connector in the radial direction and makes contact with the end face of one end of the air cavity outer cylinder. The second supporting surface and the third supporting surface are arranged at one end of the air cavity joint along the axial direction and are in contact with the air cavity outer cylinder; the fourth supporting face and the fifth supporting face are arranged on the inner wall of the air cavity connector in the axial direction and make contact with the outer wall of the air cavity mandrel. And the air cavity joint is in threaded connection with the air cavity outer cylinder. A first sealing ring is arranged on the air cavity connector and located between the air cavity connector and the air outer cylinder. Through cooperation of the multiple supporting faces, the pressure bearing strength of the air cavity is improved.

Description

Technical Field

[0001] This utility model relates to a structure for improving the pressure-bearing strength of an air cavity, belonging to the field of downhole tools for oil and gas wells. Background Technology

[0002] Air chambers are a common structure on downhole oil well tools, bearing the absolute pressure of the annulus and tubing. The pressure-bearing capacity of air chambers often limits the application of tools in high-temperature and high-pressure wells.

[0003] There are currently two ways to increase the pressure resistance of an air cavity:

[0004] One approach is to use high-strength, corrosion-resistant alloys resistant to sulfur to process air cavity parts. However, high-strength, corrosion-resistant alloys are expensive, resulting in high processing costs and significantly increasing operating costs.

[0005] Another approach is to increase the wall thickness of the air cavity components, increase the outer diameter, and decrease the bore diameter. Increasing the outer diameter limits the tripping resistance of the working string and the applicable casing range, while decreasing the bore diameter reduces the flow rate and also limits other operations such as ball dropping, pumping, and coiled tubing. Utility Model Content

[0006] This invention designs and develops a structure to improve the pressure-bearing strength of an air cavity. By cooperating with multiple support surfaces, the pressure-bearing strength of the air cavity is improved.

[0007] The technical solution provided by this utility model is as follows:

[0008] A structure for improving the pressure-bearing strength of an air cavity includes:

[0009] Air cavity outer cylinder;

[0010] An air cavity connector, one end of which extends into and is fixed to the inner wall of the outer cylinder of the air cavity;

[0011] An air cavity mandrel is axially disposed inside the outer cylinder of the air cavity and the air cavity connector;

[0012] A first support surface is radially disposed on the air cavity connector and contacts the end face of one end of the outer cylinder of the air cavity;

[0013] The second and third support surfaces are axially disposed at one end of the air cavity connector and are in contact with the outer cylinder of the air cavity.

[0014] The fourth and fifth support surfaces are arranged axially on the inner wall of the air cavity connector and contact the outer wall of the air cavity mandrel.

[0015] Preferably, the air cavity connector and the air cavity outer cylinder are connected by threads.

[0016] Preferably, a first sealing ring is provided on the air cavity connector between the air cavity connector and the air outer cylinder.

[0017] Preferably, a second sealing ring and a third sealing ring are sequentially arranged on the air cavity mandrel from one end to the other.

[0018] Preferably, the second sealing ring is located between the air cavity mandrel and the air cavity connector, and the third sealing ring is located between the air cavity mandrel and the air cavity outer cylinder.

[0019] Preferably, an air cavity is formed between the air cavity connector for installing the first sealing ring, the air chamber mandrel for installing the second and third sealing rings, and the outer cylinder of the air cavity.

[0020] The beneficial effects described in this utility model are as follows:

[0021] The structure for improving the pressure-bearing strength of the air cavity provided by this utility model improves the pressure-bearing strength of the air cavity without increasing the wall thickness of the air cavity or using high-strength corrosion-resistant alloys, through the mutual cooperation of various support surfaces. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure for improving the pressure-bearing strength of the air cavity according to the present invention. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0024] like Figure 1 As shown, this utility model provides a structure for improving the pressure-bearing strength of an air cavity, including: an air cavity connector 1, an air cavity outer cylinder 2, an air cavity mandrel 3, an air cavity 4, a first support surface 5, a second support surface 6, a third support surface 7, a fourth support surface 8, a fifth support surface 9, a first sealing ring 10, a second sealing ring 11, and a third sealing ring 12.

[0025] One end of the air cavity connector 1 extends into and is fixed on the inner wall of the air cavity outer cylinder 2. The air cavity mandrel 3 is axially arranged inside the air cavity outer cylinder 2 and the air cavity connector 1. A first support surface 5, a second support surface 6, a third support surface 7, a fourth support surface 8, and a fifth support surface 9 are machined and provided on the air cavity connector 1.

[0026] The first support surface 5 is radially disposed on the air cavity connector 1 and contacts the end face of one end of the air cavity outer cylinder 2. The second support surface 6 and the third support surface 7 are axially disposed on the outer end of the air cavity connector 1 and simultaneously contact the inner wall of the air cavity outer cylinder 2. The fourth support surface 8 and the fifth support surface 9 are axially disposed on the inner wall of the air connector and simultaneously contact the outer wall of the air cavity mandrel 3.

[0027] In this invention, as a preferred embodiment, the air cavity connector 1 is connected to the air cavity outer cylinder 2 via a thread. The air cavity mandrel 3 passes through the air cavity outer cylinder and the air cavity connector 1.

[0028] The first sealing ring 10 is disposed on the air cavity connector 1 and is located between the air cavity connector 1 and the air cavity outer cylinder 2; the second sealing ring 11 and the third sealing ring 12 are respectively disposed on the air cavity mandrel 3, wherein the second sealing ring 11 is located between the air cavity mandrel 3 and the air cavity connector 1, and the third sealing ring 12 is located between the air cavity mandrel 3 and the air cavity outer cylinder 2; the air cavity connector 1 with the first sealing ring 10 installed, the air cavity mandrel 3 with the second sealing ring 11 and the third sealing ring 12 installed, and the air cavity outer cylinder 2 form an air cavity 4.

[0029] The outer cylinder 2 of the air chamber bears the absolute pressure of the annulus; the mandrel 3 of the air chamber bears the absolute pressure inside the tubing.

[0030] When the outer cylinder 2 of the air cavity is subjected to the external extrusion pressure of the annulus, the first support surface 5, the second support surface 6 and the third support surface 7 support the outer cylinder 2 of the air cavity, thereby improving the strength of the outer cylinder 2 of the air cavity to withstand the external extrusion pressure.

[0031] When the air cavity mandrel 3 is subjected to the expansion pressure inside the tubing, the fourth support surface 8 and the fifth support surface 9 support the air cavity mandrel 3, thereby increasing the strength of the air cavity mandrel 3 to withstand the expansion pressure inside the tubing.

[0032] The structure for improving the pressure-bearing strength of the air cavity provided by this utility model improves the pressure-bearing strength of the air cavity through the cooperation of multiple support surfaces without increasing the wall thickness of the air cavity or using high-strength corrosion-resistant alloys.

[0033] Although the embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this utility model. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A structure for improving the pressure-bearing strength of an air cavity, characterized in that, include: Air cavity outer cylinder; An air cavity connector, one end of which extends into and is fixed to the inner wall of the outer cylinder of the air cavity; An air cavity mandrel is axially disposed inside the outer cylinder of the air cavity and the air cavity connector; A first support surface is radially disposed on the air cavity connector and contacts the end face of one end of the outer cylinder of the air cavity; The second and third support surfaces are axially disposed at one end of the air cavity connector and contact the inner wall of the outer cylinder of the air cavity. The fourth and fifth support surfaces are arranged axially on the inner wall of the air cavity connector and contact the outer wall of the air cavity mandrel.

2. The structure for improving the pressure-bearing strength of the air cavity according to claim 1, characterized in that, The air cavity connector is connected to the outer cylinder of the air cavity by a thread.

3. The structure for improving the pressure-bearing strength of the air cavity according to claim 2, characterized in that, A first sealing ring is provided on the air cavity connector between the air cavity connector and the outer cylinder of the air cavity.

4. The structure for improving the pressure-bearing strength of the air cavity according to claim 3, characterized in that, On the air chamber spindle, a second sealing ring and a third sealing ring are sequentially arranged from one end to the other.

5. The structure for improving the pressure-bearing strength of the air cavity according to claim 4, characterized in that, The second sealing ring is located between the air cavity mandrel and the air cavity connector, and the third sealing ring is located between the air cavity mandrel and the air cavity outer cylinder.

6. The structure for improving the pressure-bearing strength of the air cavity according to claim 5, characterized in that, An air cavity is formed between the air cavity connector for installing the first sealing ring, the air chamber mandrel for installing the second and third sealing rings, and the outer cylinder of the air cavity.

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