High-sulfur-resistance austenitic stainless steel seamless casing pipe for oil well

Abstract

The utility model provides a high sulfur resistance austenitic stainless steel seamless casing pipe for an oil well, which comprises oil well casing pipes, casing pipe connecting flange plates, connecting bolts and fixing nuts, the casing pipe connecting flange plates are fixedly arranged at two ends of the oil well casing pipes, and the oil well casing pipes are in butt joint through the casing pipe connecting flange plates at two ends of the oil well casing pipes. The connecting bolts and the fixing nuts are fixedly connected; due to the arrangement of the oil well casing pipe and the casing pipe connecting flange plate, the integral strength is high, the sulfur resistance is good, and the oil well casing pipe can be stably installed in an oil well.

Description

Technical Field

[0001] This utility model relates to the field of oil well casing technology, and in particular to a high sulfur-resistant austenitic stainless steel seamless casing for oil wells. Background Technology

[0002] In oil and gas extraction, well casing is a crucial piece of equipment, responsible for supporting the wellbore, preventing groundwater contamination, and transporting oil and gas. However, due to the unique operating environment of oil wells, such as high sulfur content, high temperature and pressure, and corrosive media, traditional well casing often faces problems such as corrosion, wear, and breakage, seriously affecting the safe and stable operation of oil wells. Furthermore, existing well casing structures still suffer from low overall strength, insufficient sulfur resistance, and inability to be stably installed inside oil wells.

[0003] Therefore, it is essential to invent a seamless casing made of high sulfur-resistant austenitic stainless steel for oil wells. Utility Model Content

[0004] To address the aforementioned technical problems, this utility model provides a high-sulfur-resistant austenitic stainless steel seamless casing for oil wells. This solves the issues of existing oil well casing structures having low overall strength, lacking adequate sulfur resistance, and being unable to be stably installed inside oil wells. The high-sulfur-resistant austenitic stainless steel seamless casing for oil wells includes an oil well casing, casing connecting flanges, connecting bolts, and fixing nuts. The casing connecting flanges are fixedly installed at both ends of the oil well casing, and the oil well casings are butt-jointed via the casing connecting flanges at both ends and fixedly connected by connecting bolts and fixing nuts.

[0005] The oil well casing includes a support pipe body, a flow guiding and protective pipe wall, an outer protective shell, and support corrugations. The flow guiding and protective pipe wall is fixedly installed on the inner wall of the support pipe body, and the outer protective shell is fixedly installed on the outer wall of the support pipe body. The support corrugations are fixedly installed on the surface of the outer protective shell.

[0006] The casing connection flange includes a support plate structure, a concrete guide port, and a fixed connection hole. The support plate structure is fixedly installed at both ends of the oil well casing. The concrete guide port is opened inside the support plate structure. The fixed connection hole is opened inside the support plate structure, and the concrete guide port and the fixed connection hole are staggered inside the support plate structure.

[0007] The oil well casing is made of several seamless austenitic stainless steel pipes, and multiple oil well casings are connected by casing flanges to form a long pipe. The wall of the flow-guiding and protective pipe is made of a layer of titanium alloy metal pipe. The outer protective shell is made of a carbon steel metal pipe, and the supporting corrugations are made of several parallel carbon steel metal rings with consistent gaps between them. It has the following functions: ① Preventing formation collapse: After the oil well casing is installed, it can prevent formation collapse and ensure the stability of the wellbore. Formation stability is the foundation of oil well safety and production. The oil well casing can protect the formation around the wellbore from damage and collapse; ② Isolating the formation: During the drilling process, the oil well casing is used to isolate different formations to prevent cross-contamination of well fluids between different formations and maintain the purity of the oil and gas layer; ③ Stability after installation: After the oil well casing is installed, concrete is filled between the oil well casing and the wellbore wall. The supporting corrugations allow the utility model to be more tightly connected to the well wall through the concrete, preventing changes in position.

[0008] The casing connection flange plate is made of a circular austenitic stainless steel metal plate, and the concrete guide port has several sets of openings. The concrete guide port is evenly distributed inside the support plate structure and has the following functions: ① Connecting the casing: The casing connection flange plate is used to connect the two ends of the oil well casing. By being fixedly installed at both ends of the oil well casing, the casing connection flange plate can stably connect the oil well casing together to form a complete pipeline system. This connection method helps to ensure the sealing between the casings and the stability of the structure; ② Concrete flow: The setting of the concrete guide port facilitates the flow of concrete between the oil well casing and the well wall, which is convenient for high-strength fixing of this utility model.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] 1. The oil well casing of this utility model has the following functions: ① Preventing formation collapse: After drilling is completed, the oil well casing can prevent formation collapse and ensure the stability of the wellbore. Formation stability is the foundation of oil well safety and production. The oil well casing can protect the formation around the wellbore from damage and collapse; ② Isolating formations: During drilling, the oil well casing is used to isolate different formations to prevent cross-contamination of well fluids between different formations and maintain the purity of the oil and gas layer; ③ Stability after installation: After the oil well casing is installed, concrete is filled between the oil well casing and the wellbore wall. The corrugated support allows this utility model to be more tightly connected to the well wall through the concrete, preventing changes in position.

[0011] 2. The casing connection flange plate of this utility model has the following functions: ① Connecting the casing: The casing connection flange plate is used to connect the two ends of the oil well casing. By being fixedly installed at both ends of the oil well casing, the casing connection flange plate can stably connect the oil well casing together to form a complete pipeline system. This connection method helps to ensure the sealing between the casings and the stability of the structure; ② Concrete flow: The setting of the concrete guide port facilitates the flow of concrete between the oil well casing and the well wall, which is convenient for high-strength fixing of this utility model. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model.

[0013] Figure 2 This is an enlarged view of section A of this utility model.

[0014] Figure 3 This is an enlarged view of section B of this utility model.

[0015] In the picture:

[0016] Oil well casing 1, support pipe body 11, flow guiding and protective pipe wall 12, outer protective shell 13, support corrugated 14, casing connecting flange plate 2, support plate structure 21, concrete guide port 22, fixed connection hole 23, connecting bolt 3, fixing nut 4. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0018] As attached Figure 1 To be continued Figure 3 As shown.

[0019] This utility model provides a high sulfur-resistant austenitic stainless steel seamless casing for oil wells, including an oil well casing 1, a casing connecting flange plate 2, connecting bolts 3 and fixing nuts 4, wherein: the casing connecting flange plate 2 is fixedly installed at both ends of the oil well casing 1, and the oil well casing 1 is butted together through the casing connecting flange plates 2 at both ends, and fixedly connected by connecting bolts 3 and fixing nuts 4.

[0020] The oil well casing 1 includes a support pipe body 11, a flow guiding and protective pipe wall 12, an outer protective shell 13, and a support corrugation 14. The flow guiding and protective pipe wall 12 is fixedly installed on the inner wall of the support pipe body 11, and the outer protective shell 13 is fixedly installed on the outer wall of the support pipe body 11. The support corrugation 14 is fixedly installed on the surface of the outer protective shell 13.

[0021] The casing connection flange plate 2 includes a support plate structure 21, a concrete guide port 22, and a fixed connection hole 23. The support plate structure 21 is fixedly installed at both ends of the oil well casing 1. The concrete guide port 22 is opened inside the support plate structure 21. The fixed connection hole 23 is opened inside the support plate structure 21, and the concrete guide port 22 and the fixed connection hole 23 are staggered inside the support plate structure 21.

[0022] This utility model provides a high sulfur-resistant austenitic stainless steel seamless casing for oil wells.

[0023] 1. Material Selection

[0024] The well casing 1 is made of high sulfur-resistant austenitic stainless steel to ensure good corrosion resistance in high sulfur environment. Specifically, the main body of the casing is made of high-quality austenitic stainless steel, while the flow guide and protection pipe wall 12 is made of titanium alloy metal pipe, and the outer protective shell 13 and the support corrugation 14 are made of carbon steel metal pipe or ring.

[0025] 2. Structural Design

[0026] The oil well casing 1 includes a casing body, a connecting flange plate 2, connecting bolts 3 and fixing nuts 4. The casing connecting flange plate 2 is fixedly installed at both ends of the casing to realize the butt connection between the oil well casings. The support corrugated 14 is fixedly installed on the surface of the outer protective shell 13 to enhance the structural strength and stability of the casing.

[0027] 3. Flow guidance and protection design

[0028] To effectively prevent high-sulfur compounds in oil wells from corroding the casing, a flow-guiding protective pipe wall 12 was designed. This flow-guiding protective pipe wall 12 is fixedly installed on the inner wall of the casing and can guide the concrete to flow between the oil well casing 1 and the well wall, facilitating high-strength fixing of this utility model.

[0029] 4. Connection method

[0030] The connecting bolt 3 and the fixing nut 4 are fixedly connected through the connecting hole 23 to ensure that the connection of the oil well casing 1 is firm and will not loosen or fall off due to changes in working conditions.

[0031] 5. Specific Implementation Steps

[0032] First, the casing connection flange plate 2 of the oil well casing 1 is fixedly installed at both ends of the casing to ensure a firm connection.

[0033] Next, the flow guide and protection pipe wall 12 is fixedly installed on the inner wall of the casing to protect the casing from corrosion by high sulfur compounds.

[0034] Then, the outer protective shell 13 is fixedly installed on the outer wall of the sleeve, and the supporting corrugations 14 are installed to enhance the structural stability.

[0035] Finally, the connection is secured using connecting bolts 3 and fixing nuts 4 to ensure the stable operation of the entire oil well casing system.

[0036] These specific implementation methods ensure that the well casing can operate stably under harsh working conditions and effectively extend its service life.

[0037] Any technical solution that achieves the above-mentioned technical effects by utilizing the technical solution described in this utility model, or by designing a similar technical solution inspired by the technical solution described in this utility model, falls within the protection scope of this utility model.

Claims

1. A high-sulfur-resistant austenitic stainless steel seamless casing for oil wells, characterized in that: The invention includes an oil well casing (1), a casing connecting flange plate (2), connecting bolts (3), and fixing nuts (4), wherein: the casing connecting flange plate (2) is fixedly installed at both ends of the oil well casing (1), and the oil well casing (1) is butt-jointed through the casing connecting flange plates (2) at both ends, and fixedly connected by connecting bolts (3) and fixing nuts (4); characterized in that: the casing connecting flange plate (2) includes a support plate structure (21), a concrete guide port (22), and a fixing connection hole (23). The support plate structure (21) is fixedly installed at both ends of the oil well casing (1), and the concrete guide port (22) is opened inside the support plate structure (21); the fixed connection hole (23) is opened inside the support plate structure (21), and the concrete guide port (22) and the fixed connection hole (23) are interleaved inside the support plate structure (21); the oil well casing (1) is made of several austenitic stainless steel seamless steel pipes, and multiple oil well casings (1) are connected to a long pipe by casing connecting flange plate (2).

2. The high sulfur-resistant austenitic stainless steel seamless casing for oil wells as described in claim 1, characterized in that: The well casing (1) includes a support pipe body (11), a flow-guiding and protective pipe wall (12), an outer protective shell (13), and a support corrugation (14). The flow-guiding and protective pipe wall (12) is fixedly installed on the inner wall of the support pipe body (11), and the outer protective shell (13) is fixedly installed on the outer wall of the support pipe body (11). The support corrugation (14) is fixedly installed on the surface of the outer protective shell (13). The flow-guiding and protective pipe wall (12) is made of a layer of titanium alloy metal pipe. The outer protective shell (13) is made of a carbon steel metal pipe, and the support corrugation (14) is made of several parallel carbon steel metal rings with consistent gaps between them.

3. The high sulfur-resistant austenitic stainless steel seamless casing for oil wells as described in claim 1, characterized in that: The sleeve connection flange plate (2) is a circular austenitic stainless steel metal plate, and the concrete guide port (22) has several sets of openings, which are evenly distributed inside the support plate structure (21).

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