A bimetallic composite pipe that can be fitted with a process attachment and a method of manufacturing the same

Abstract

The application discloses a double-metal composite pipe capable of assembling process accessories and a manufacturing method thereof, and belongs to the technical field of composite pipe preparation. The double-metal composite pipe comprises a base pipe, a corrosion-resistant alloy lining pipe lined in the base pipe, and a reinforcing layer between the base pipe and the lining pipe. The base pipe and the lining pipe are both provided with through holes with internal threads, and are assembled with external connecting pieces with external threads. The double-metal composite pipe capable of assembling process accessories disclosed by the application can not only improve the buckling failure resistance and assemble process accessories on the basis of ensuring the economy and use performance of traditional composite pipes, but also can reduce the damage of welding operation in the manufacturing and on-site application processes to the composite pipe body.

Description

Technical Field

[0001] This invention belongs to the field of composite tube preparation technology, specifically relating to a bimetallic composite tube that can be assembled with process accessories and its manufacturing method. Background Technology

[0002] In recent years, oil and gas fields have widely used bimetallic composite pipes in their gathering and transportation pipelines. These pipes rely on a corrosion-resistant alloy lining inside a carbon steel base pipe to achieve both corrosion protection and pressure resistance. However, currently, the base pipe and lining of composite pipes are not metallurgically bonded, resulting in a high risk of lining buckling failure during use. Furthermore, a complete process pipeline requires sections with process accessories to facilitate the mixing / diversion of transported media and the monitoring of pipeline data. This necessitates that composite pipes not only improve their resistance to buckling failure but also enable the connection of process accessories. However, the double-layer structure of existing composite pipes makes on-site drilling difficult, and the drilling operation also damages the integrity of the corrosion-resistant layer and reduces the pipeline's corrosion resistance, making it impossible to install process accessories on the finished pipeline.

[0003] To address the above issues, while pure corrosion-resistant alloy pipes meet the performance requirements, they are not economically feasible. Metallurgically bonded composite pipes are technically immature due to incompatibility issues between the heat treatment processes of the base pipe and the corrosion-resistant alloy layer. Existing technologies struggle to simultaneously improve resistance to collapse and accommodate the installation of process accessories. Therefore, there is an urgent need for a structurally sound, economical corrosion-resistant pipe material and its manufacturing process that can accommodate process accessories, thus meeting the requirements of process pipelines. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a bimetallic composite pipe that can be fitted with process accessories and its manufacturing method, which solves the problems of high buckling risk, difficulty in drilling and welding operations, and inability to connect process accessories to the pipeline.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] This invention provides a bimetallic composite pipe with assembleable process accessories, comprising a base pipe, a liner, and a reinforcing layer, wherein the liner is disposed inside the base pipe, and the reinforcing layer is disposed between the base pipe and the liner;

[0007] Both the base tube and the liner tube have through holes, and the through holes of the base tube are connected to connectors.

[0008] Furthermore, the base tube is made of carbon steel or low alloy steel; the liner is made of stainless steel, iron-nickel based alloy, or nickel-based alloy.

[0009] Furthermore, in this invention, the reinforcing layer is a high-temperature resistant epoxy resin adhesive material.

[0010] Furthermore, the present invention provides that the base tube has a base tube through hole and the liner tube has a liner tube through hole; the base tube through hole and the liner tube through hole are coaxial, and the diameter of the base tube through hole is larger than the diameter of the liner tube through hole.

[0011] Furthermore, in this invention, the diameter of the through hole of the base tube is the same as the outer diameter of the connector, and the end of the internal thread of the through hole of the base tube is provided with a contact surface I, the angle between the contact surface I and the vertical direction is 5° to 15°, and the length of the contact surface I is 2.0 to 4.0 mm.

[0012] Furthermore, in this invention, the diameter of the through hole of the liner is the same as the inner diameter of the connector, and a contact surface II is provided at the difference between the through hole of the liner and the through hole of the base pipe. The contact surface II is inclined to one side of the base pipe, and the angle between the contact surface II and the horizontal direction is 5° to 20°.

[0013] Furthermore, the connector includes a threaded portion and a non-threaded portion, wherein the threaded portion of the connector is threadedly connected to the through hole of the base tube.

[0014] Furthermore, in this invention, the height of the connector is greater than the wall thickness of the bimetallic composite pipe.

[0015] Furthermore, the non-threaded portion of the connector matches the dimensions of the process accessory to be assembled.

[0016] This invention provides a method for manufacturing the bimetallic composite tube with assemblable process accessories, comprising the following steps:

[0017] S1: A through hole is made in the base pipe, and a contact surface I is made at the threaded end of the through hole. A process plug that matches the through hole is installed. Then, the inner surface of the base pipe is sandblasted and blown, and a reinforcing layer is sprayed to obtain a base pipe with a reinforcing layer.

[0018] S2: The liner is fitted inside the base pipe with the reinforcing layer, the liner is aligned with the axis of the base pipe, and the pipe is composited using a mechanical expansion process;

[0019] S3: After removing the process plug, clean the overflowing reinforcement layer, and open a liner through hole that is aligned with the axis of the base pipe through hole and smaller than the diameter of the base pipe through hole. A contact surface II is opened on the difference between the liner and the base pipe.

[0020] S4: Apply a reinforcing layer to contact surface I and contact surface II, install the connector, and obtain a bimetallic composite pipe that can be assembled with process accessories.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The bimetallic composite pipe with assembleable process accessories disclosed in this invention, while ensuring the economy and performance of traditional composite pipes, integrates the base pipe and the corrosion-resistant alloy layer with a reinforcing layer, which greatly improves the ability of the bimetallic composite pipe process pipeline to resist buckling failure; the setting of external connectors facilitates the assembly of various process accessories, enabling the bimetallic composite pipe process pipeline to have the functions of conveying medium confluence / diversion and monitoring pipeline data.

[0023] Furthermore, the bimetallic composite pipe preparation method for assemblable process accessories disclosed in this invention constructs a complete and sealed channel for the corrosion-resistant alloy liner through the material and structural design of the base pipe through hole, the liner through hole, and the reinforcing layer, ensuring the corrosion resistance of the pipe. The reinforcing layer reduces the risk of liner deformation and peeling from the base pipe during the liner through hole processing. The threaded sealing design eliminates welding operations during manufacturing and keeps welding operations away from the composite pipe body during on-site assembly, further reducing damage to the composite pipe body caused by welding operations.

[0024] Furthermore, the use of connectors solves the processing problem of the double-layer structure of composite pipes, adds a direct connection channel for process accessories in on-site assembly, and also keeps the welding operation during assembly away from the composite pipe body, further reducing the damage to the composite pipe body, especially the reinforcing layer and corrosion resistance, caused by welding operations.

[0025] Furthermore, by using the structural design of contact surface I and contact surface II, combined with the use of reinforcing layer materials on the two contact surfaces and lining material on contact surface I, a sealed channel with low contact stress and isolated by corrosion-resistant materials can be constructed. This prevents the medium inside the pipe from entering the interlayer of the base pipe / lining / connector, thus ensuring the integrity of the corrosion resistance of the composite pipe. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the bimetallic composite pipe without connectors according to the present invention.

[0027] Figure 2 This is a schematic diagram of the process plug structure described in this invention.

[0028] Figure 3 This is a schematic diagram of the connector structure described in this invention.

[0029] Figure 4 This is a schematic diagram of the structure of a bimetallic composite tube that can be assembled with process accessories according to the present invention.

[0030] Among them, 1-base pipe; 2-liner pipe; 3-reinforcing layer; 4-base pipe through hole; 5-process plug; 6-liner pipe through hole; 7-connector. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 scope of protection of the present invention.

[0032] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0033] The present invention will now be described in further detail with reference to the accompanying drawings:

[0034] This invention discloses a bimetallic composite tube that can be assembled with process accessories, see [link to related document]. Figure 1 , Figure 3 and Figure 4 The composite pipe includes a base pipe 1, a liner pipe 2, and a reinforcing layer 3. The composite pipe is provided with a base pipe through hole 4 with internal threads, a process plug 5, a liner pipe through hole 6, and a connector 7 with external threads. The diameter of the base pipe through hole 4 is larger than the diameter of the liner pipe through hole 6.

[0035] like Figure 1As shown, the base pipe 1 is made of carbon steel or low alloy steel, the liner 2 is made of stainless steel, iron-nickel based alloy, or nickel-based alloy, and the reinforcing layer 3 uses high-temperature resistant epoxy resin adhesive. The diameter D1 of the base pipe through hole 4 is the same as the outer diameter of the connector 7. The end of the internal thread of the base pipe through hole 4 is machined with a contact surface I with an angle α1 of 5° to 15° with the vertical direction and a length L of 2.0 to 4.0 mm. The main thread is a round thread or a trapezoidal thread. The liner through-hole 6 and the base pipe through-hole 4 are coaxial. The diameter D2 of the liner through-hole 6 is the same as the inner diameter of the threaded end of the connector 7. The diameter of the base pipe through-hole 4 is the same as the outer diameter of the connector 7. The portion of the liner 2 extending out of the base pipe through-hole 4 at the liner through-hole 6 is inclined towards the base pipe 1, forming a contact surface II with an angle α2 of 5° to 20°. That is, the difference between the liner through-hole 6 and the base pipe through-hole 4 is provided with contact surface II. The contact surface II is inclined towards the base pipe 1, and the angle between the contact surface II and the horizontal direction is 5° to 20°. The outer diameter of the connector 7 is D1, and the inner diameter of the threaded end of the connector 7 is D2. The connector 7 includes a threaded end and a non-threaded end. The threaded end of the connector 7 is connected to the internal thread of the base pipe through-hole 4 of the base pipe 1. The dimensions of the non-threaded end and its length protruding from the composite pipe match the dimensions of the process accessories to be assembled, and the design of the threaded end matches the design of the internal thread of the base pipe through-hole 4. The material of connector 7 should preferably be a pure material with corrosion resistance comparable to or better than that of the lining and meeting the strength requirements, or a bimetallic composite pipe section formed by overlaying welding with welding materials of higher corrosion resistance onto carbon steel of the same material as the base pipe. The height of connector 7 is greater than the wall thickness of base pipe 1.

[0036] The above-mentioned method for preparing a bimetallic composite tube that can be assembled with process accessories is specifically implemented according to the following steps:

[0037] Step 1: First, machine a through hole 4 with internal threads and a diameter of D1 on the base pipe 1. The threaded end of the through hole 4 has a contact surface I with an angle of α1 and a length of L. Install a thread-matching... Figure 2 The process plug 5 is shown, and then the inner surface of the base pipe 1 is sandblasted and blew before the reinforcement layer 3 is sprayed on.

[0038] Step 2: Insert the liner 2 into the base pipe 1, aligning its axis with the axis of the base pipe 1, and complete the pipe composite operation using a mechanical expansion process.

[0039] Step 3: Remove the process plug 5, clean the reinforcing layer 3 overflowing at the corresponding position of the base pipe through hole 4, and use a processing method with cooling measures to process a liner 2 through hole 6 with a diameter of D2. The liner through hole 6 and the base pipe through hole 4 are axially aligned. Use a mechanical method to tilt the liner 2 extending from the base pipe through hole 4 towards the base pipe 1 at an angle α2 to form a contact surface II.

[0040] Step 4: Apply reinforcing layer 3 to contact surface I and contact surface II, install connector 7, and manufacturing is complete.

[0041] The present invention discloses a bimetallic composite pipe that can be fitted with process accessories. While ensuring the economy and performance of traditional composite pipes, it not only improves the resistance to buckling failure but also allows for the assembly of process accessories. At the same time, it can reduce the damage to the composite pipe body caused by welding operations during manufacturing and field application.

[0042] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for manufacturing a bimetallic composite pipe with assemblable process accessories, characterized in that, Includes the following steps: S1: A through hole (4) is made in the base pipe (1). A contact surface I is made at the threaded end of the through hole (4). A process plug (5) matching the through hole (4) is installed. Then, the inner surface of the base pipe is sandblasted and blown cleaned and a reinforcing layer (3) is sprayed to obtain a base pipe (1) with a reinforcing layer (3). S2: The liner (2) is fitted inside the base pipe (1) with the reinforcing layer (3), the liner (2) and the base pipe (1) are aligned, and the pipe is composited by mechanical expansion process; S3: After removing the process plug (5), clean the overflowing reinforcement layer (3), and open a liner through hole (6) in the liner (2) that is aligned with the axis of the base pipe through hole (4) and smaller than the diameter of the base pipe through hole (4). A contact surface II is opened on the difference between the liner (2) and the base pipe (1). S4: Apply a reinforcing layer (3) to contact surface I and contact surface II, install the connector (7), and obtain a bimetallic composite pipe that can be assembled with process accessories; The bimetallic composite pipe for the assemblable process accessories includes a base pipe (1), a liner (2) and a reinforcing layer (3). The liner (2) is disposed inside the base pipe (1), and the reinforcing layer (3) is disposed between the base pipe (1) and the liner (2). Both the base tube (1) and the liner tube (2) are provided with through holes, and the through holes of the base tube (1) are connected to connectors (7).

2. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 1, characterized in that, The base tube (1) is made of carbon steel or low alloy steel; the liner tube (2) is made of stainless steel, iron-nickel alloy or nickel alloy.

3. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 1, characterized in that, The reinforcing layer (3) is a high-temperature resistant epoxy resin adhesive material.

4. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 1, characterized in that, The base tube (1) has a base tube through hole (4), and the liner tube (2) has a liner tube through hole (6); the base tube through hole (4) and the liner tube through hole (6) are coaxial, and the diameter of the base tube through hole (4) is larger than the diameter of the liner tube through hole (6).

5. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 4, characterized in that, The diameter of the through hole (4) of the base tube is the same as the outer diameter of the connector (7). The end of the internal thread of the through hole (4) of the base tube is provided with a contact surface I. The angle between the contact surface I and the vertical direction is 5°~15° and the length of the contact surface I is 2.0~4.0mm.

6. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 4, characterized in that, The diameter of the liner through hole (6) is the same as the inner diameter of the connector (7). The liner through hole (6) and the base pipe through hole (4) are provided with a contact surface II. The contact surface II is inclined to one side of the base pipe (1). The angle between the contact surface II and the horizontal direction is 5°~20°.

7. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 1, characterized in that, The connector (7) includes a threaded portion and a non-threaded portion, and the threaded portion of the connector (7) is threadedly connected to the through hole of the base tube (1).

8. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 7, characterized in that, The height of the connector (7) is greater than the wall thickness of the base pipe (1).

9. The method for manufacturing a bimetallic composite tube with assemblable process accessories according to claim 7, characterized in that, The non-threaded portion of the connector (7) matches the dimensions of the process accessory to be assembled.

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