A composite continuous pipe with high external pressure resistance and high temperature resistance

Abstract

The present invention relates to the technical field of oil pipelines, and discloses a high-pressure-resistant and high-temperature-resistant composite continuous pipe, comprising an outer pipe layer, a pipe assembly arranged in the outer pipe layer, and a centralizer sleeved on the outer side of the outer pipe layer, the outer side of the pipe assembly is sleeved with a plurality of support rings, the plurality of support rings are spaced and distributed on the outer wall of the pipe assembly, a rolling assembly is provided between the inner side of the pipe assembly and the outer side of the pipe assembly, and the pipe assembly moves along the axis of the pipe assembly from the inner side of the outer pipe layer through the rolling assembly. The present invention provides an outer pipe layer on the outer side of the pipeline, so that the pipe assembly can be separated from the underground in the case of sand burial, etc., and rolling friction is used to replace traditional sliding friction to avoid deformation of the pipe assembly due to heat generated by friction. A structure that can continuously update the lubricating layer is provided in the rolling element, and the mixed grease effectively enters the friction interface to play a role of rapid heat conduction and lubrication, thereby reducing the probability of the pipeline being broken.

Description

Technical Field

[0001] The invention relates to the field of oil pipelines, and more specifically to a high-pressure-resistant and high-temperature-resistant composite continuous pipe. Background Art

[0002] At present, steel pipes are usually used for water injection pipelines in oil wells in oil fields. Steel pipes have the disadvantages of poor corrosion resistance, short length of a single pipe (need to be connected when lowered into the well), heavy weight, long operation time, and breaking when buried in sand during recovery.

[0003] Therefore, composite materials are used to replace traditional steel pipe structures. However, when ordinary composite continuous pipes are buried in oil production and subjected to high temperatures, the pipe body softens and collapses under the action of external forces, making them unusable.

[0004] The pipeline is made of high-temperature resistant materials and a support layer is provided on the outside of the pipeline to improve the overall support strength of the pipeline, thereby improving the pipeline's pressure resistance and high-temperature resistance. However, when the pipeline is extended into the well for use, if it is buried in sand or stuck, the pipeline will be broken if it is pulled hard due to its instability under high temperature conditions. At the same time, when the pipeline is pulled out from the well, the sliding friction of the pipe wall will generate heat, causing the pipeline material to be unstable, resulting in deformation of the pipeline, and the force used to pull out the pipeline will exceed the tensile limit of the pipeline, causing damage. Summary of the invention

[0005] The present invention provides a high external pressure and high temperature resistant composite continuous pipe, which solves the technical problem in the related art that when the pipe is drawn out, the heat generated by sliding friction makes the pipe material unstable, causing the pipe to deform, and the pipe is easily broken due to exceeding the tensile limit.

[0006] The present invention provides a high external pressure and high temperature resistant composite continuous pipe, comprising an outer pipe layer, a pipe assembly arranged in the outer pipe layer, and a centralizer sleeved on the outer side of the outer pipe layer, a plurality of support rings are sleeved on the outer side of the pipe assembly, and the plurality of support rings are distributed on the outer wall of the pipe assembly at intervals, a rolling assembly is arranged between the inner side of the pipe assembly and the outer side of the pipe assembly, and the pipe assembly moves from the inner side of the outer pipe layer along the axis of the pipe assembly through the rolling assembly;

[0007] A spiral rolling groove is provided on the inner side of the outer tube layer, and the rolling component moves along the groove direction of the rolling groove. A lubricating layer is provided on the inner side of the rolling groove, and a carrying groove is provided on the outer side of the rolling component. When the rolling component moves along the groove direction of the rolling groove, the rolling component transfers the lubricating layer from the rolling groove to the outer wall of the pipe component or the inner wall of the outer tube layer through the carrying groove.

[0008] Furthermore, the pipeline component includes an inner lining layer, a reinforcement layer and a protective layer. The reinforcement layer is arranged between the inner lining layer and the protective layer, and the protective layer is arranged on the outer wall of the pipeline component on one side close to the outer tube layer.

[0009] Furthermore, an inner support layer is provided on the outer side of the pipe assembly, and the inner support layer is provided with a support groove that rolls with the rolling assembly.

[0010] Furthermore, the inner lining layer is made of high temperature resistant cross-linked polyethylene, the reinforcing layer is made of glass fiber pre-impregnated polyethylene, and the protective layer and the outer tube layer are both made of polyethylene.

[0011] Furthermore, the support ring is made of high-strength carbon steel.

[0012] Further, the rolling assembly comprises a rolling member, and two ends of the rolling member are respectively arranged at two side gaps between the pipeline assembly and the opposite sides of the outer tube layer.

[0013] Furthermore, the rolling element includes a rolling column and a column shaft. The column shaft is arranged on the outer walls at both ends of the rolling column, and the column shaft is installed on the inner wall of the outer tube layer.

[0014] Furthermore, the carrying grooves are distributed on the outer wall of the rolling cylinder, and the vertically upward position of the rolling cylinder where the carrying grooves are opened is located above the lubricating layer.

[0015] Furthermore, the centralizer comprises a ring body and side support plates, and the side support plates are distributed in an annular shape on the outer wall of the ring body.

[0016] Furthermore, the inner side wall of the ring body is provided with pressing parts near both end surfaces of the ring body, and the position where the centralizer is fixed on the outer side of the outer pipe layer corresponds to the position where the support ring is fixed on the pipeline assembly.

[0017] The beneficial effects of the present invention are as follows: the coiled pipe replaces the traditional water injection pipe with a composite pipe, the softening temperature of the composite pipe material is higher than the temperature of the oil-water mixture being transported, and will not collapse due to high temperature. At the same time, a support ring is provided inside, which can effectively improve the circumferential strength of the pipe;

[0018] At the same time, an outer tube layer is provided on the outside of the pipeline, so that the pipeline components can be separated from the underground in case of sand burial, etc., and rolling friction is used instead of traditional sliding friction to avoid deformation of the pipeline components due to heat generated by friction, which affects the extraction of the pipeline. At the same time, a structure that can continuously update the lubricating layer is provided in the rolling element, and the mixed grease effectively enters the friction interface to play a role in rapid heat conduction and lubrication, further improving the efficiency of extracting the pipeline components from the outer tube layer and reducing the probability of the pipeline being pulled apart. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the main structure of a high external pressure and high temperature resistant composite continuous pipe proposed by the present invention;

[0020] Figure 2This is a front view of a high external pressure and high temperature resistant composite continuous pipe proposed by the present invention with the outer pipe layer removed;

[0021] Figure 3 The present invention Figure 2 AA cross-sectional structural diagram;

[0022] Figure 4 The present invention Figure 2 Schematic diagram of the pipe end structure;

[0023] Figure 5 It is a structural schematic diagram of a rolling element of a composite continuous pipe with high external pressure resistance and high temperature resistance proposed by the present invention;

[0024] Figure 6 The present invention is a schematic structural diagram of a centralizer for a composite continuous pipe with high external pressure resistance and high temperature resistance.

[0025] In the figure: 100, outer tube layer; 110, support part; 120, lubricating layer; 200, pipeline assembly; 210, inner lining layer; 220, reinforcement layer; 230, protective layer; 300, stabilizer; 310, ring body; 320, side support plate; 330, pressing part; 400, support ring; 500, rolling assembly; 510, rolling element; 511, rolling column; 512, column shaft; 513, carrying groove; 520, rolling groove; 530, inner support layer. DETAILED DESCRIPTION

[0026] The subject matter described herein will now be discussed with reference to example embodiments. It should be understood that the discussion of these embodiments is only to enable those skilled in the art to better understand and implement the subject matter described herein, and the functions and arrangements of the elements discussed may be changed without departing from the scope of protection of the contents of this specification. Each example may omit, replace or add various processes or components as needed. In addition, the features described relative to some examples may also be combined in other examples.

[0027] Embodiment 1

[0028] See also Figure 1-Figure 6 As shown, a high external pressure and high temperature resistant composite continuous pipe comprises an outer pipe layer 100, a pipe assembly 200 arranged in the outer pipe layer 100 and a centralizer 300 sleeved on the outer side of the outer pipe layer 100, a plurality of support rings 400 are sleeved on the outer side of the pipe assembly 200, and the plurality of support rings 400 are distributed on the outer wall of the pipe assembly 200 at intervals, a rolling assembly 500 is arranged between the inner side of the pipe assembly 200 and the outer side of the pipe assembly 200, and the pipe assembly 200 moves from the inner side of the outer pipe layer 100 along the axis of the pipe assembly 200 through the rolling assembly 500;

[0029] A spiral rolling groove 520 is provided on the inner side of the outer tube layer 100, and the rolling component 500 moves along the groove direction of the rolling groove 520. A lubricating layer 120 is provided on the inner side of the rolling groove 520, and a carrying groove 513 is provided on the outer side of the rolling component 500. When the rolling component 500 moves along the groove direction of the rolling groove 520, the rolling component 500 transfers the lubricating layer 120 from the rolling groove 520 to the outer wall of the pipe component 200 or the inner wall of the outer tube layer 100 through the carrying groove 513.

[0030] The lubricating layer 120 includes but is not limited to high temperature resistant grease, which is solidified and arranged in the rolling groove 520. When the pipeline component 200 and the outer tube layer 100 are relatively stationary, the grease adheres to the rolling groove 520 and acts as a heat conducting layer.

[0031] The pipe assembly 200 includes an inner lining layer 210, a reinforcement layer 220 and a protective layer 230. The reinforcement layer 220 is arranged between the inner lining layer 210 and the protective layer 230, and the protective layer 230 is arranged on the outer wall of the pipe assembly 200 close to the outer tube layer 100. At the same time, an inner support layer 530 is provided on the outer side of the pipe assembly 200, and the inner support layer 530 is provided with a support groove that rolls with the rolling assembly 500.

[0032] The inner lining layer 210 is made of high-temperature resistant cross-linked polyethylene, the reinforcing layer 220 is made of glass fiber pre-impregnated polyethylene, the protective layer 230 and the outer pipe layer 100 are both made of polyethylene, and the inner support layer 530 is made of high-temperature resistant polyamide-imide material, whose softening limit temperature is higher than the softening limit temperature of the pipeline assembly 200 as a whole, and the support ring 400 is made of high-strength carbon steel. During production, the inner lining layer 210 and the reinforcing layer 220 are bonded together by an infrared heating device. When the protective layer 230 is produced, as the production is running, the steel support ring 400 is clamped on the pipeline before the protective layer 230 is coated, and the protective layer 230 is bonded to the reinforcing layer 220 after coating. After the pipeline is produced, it is an integrated pipeline. When the pipeline is buried in the oil field, the pipeline will be squeezed by the soil, and the support ring 400 can play a good supporting role through the bonding of each layer to prevent the pipeline from deformation, so that the pipeline can operate effectively for a long time;

[0033] The rolling assembly 500 includes a rolling member 510, and the two ends of the rolling member 510 are respectively arranged at the two side gaps between the opposite sides of the pipeline assembly 200 and the outer tube layer 100. The rolling member 510 includes a rolling column 511 and a column shaft 512. The column shaft 512 is arranged on the outer walls of the two ends of the rolling column 511. The column shaft 512 is installed on the inner wall of the outer tube layer 100. The carrying grooves 513 are distributed on the outer wall of the rolling column 511, and the vertical upward position of the carrying grooves 513 on the rolling column 511 is located above the lubricating layer 120.

[0034] The rolling elements 510 are distributed along the spiral rolling groove 520, that is, the spirally distributed rolling elements 510 form a support belt, which further improves the support strength between the pipeline component 200 and the outer pipe layer 100. When the pipeline is subjected to a large tensile force, the pipeline component 200 can be lifted out of the well through the upper end of the pipeline component 200, and the pipeline component 200 can be effectively recovered. At this time, the spirally distributed rolling elements 510 act as a rolling belt surface, which can effectively help the pipeline component 200 to be separated from the outer pipe layer 100;

[0035] The rolling column 511 includes but is not limited to a waist drum-shaped structure, and the column shaft 512 is arranged on both ends of the rolling column 511, that is, a groove body extends inwardly on both sides of the rolling groove 520, and the groove wall of the groove body is provided with a support portion 110. The shaft surface of the column shaft 512 rolls on the wall of the support portion 110, and the column shaft 512 is installed in the rolling groove 520. The relative position of the groove direction does not change, and the rolling column 511 rotates around the column shaft 512, and the transfer of the lubricating layer is realized through the carrying groove thereon;

[0036] The centralizer 300 includes a ring body 310 and a side support plate 320. The side support plate 320 is distributed in an annular shape on the outer wall of the ring body 310. The inner wall of the ring body 310 is provided with a pressing portion 330 near the two end surfaces of the ring body 310. The position where the centralizer 300 is fixed on the outer side of the outer pipe layer 100 corresponds to the position where the support ring 400 is fixed on the pipeline assembly 200, that is, the pressing portion 330 corresponds to the position of the support ring 400, which can control the deformation of the pipeline assembly 200 between the two support rings 400 and the ring body 310.

[0037] In general, an outer tube layer 100 is provided on the outside of the pipeline, so that the pipeline component 200 can be separated from the underground in the event of sand burial, etc., and rolling friction is used instead of traditional sliding friction to avoid deformation of the pipeline component 200 due to heat generated by friction, which affects the extraction of the pipeline component 200. At the same time, a structure that can continuously update the lubricating layer 120 is provided in the rolling element 510, and the mixed grease effectively enters the friction interface, which plays a role in rapid heat conduction and lubrication, further improving the efficiency of extracting the pipeline component 200 from the outer tube layer 100 and reducing the probability of the pipeline being broken.

[0038] In one embodiment of the present invention, there are two working conditions for the high external pressure and high temperature resistant composite coiled tube. Under the two different working conditions, the specific working process is as follows:

[0039] 1. Normal water injection operating conditions

[0040] Under normal oil production conditions, the bottom end of the coiled tubing is plugged into the oil field, and water is injected below the oil level in the oil well to press out the oil-water mixture, wherein the temperature of the oil-water mixture is approximately between 80°C and 100°C, and the temperature is stably transported in the inner lining layer 210 made of high-temperature resistant cross-linked polyethylene material. The softening point temperature of the high-temperature resistant cross-linked polyethylene material can reach about 130°C, and the oil-water mixture will apply hydraulic pressure to the inner lining layer 210. At this time, the outer support ring 400 effectively controls the internal pressure of the pipeline, and at the same time, the compression part 330 in the outer centralizer 300 abuts against the connection between the ring bodies 310 of the two support rings 400, further ensuring that the pipeline assembly 200 between the support rings 400 expands, and the outer spirally arranged rolling elements 510 form a support belt, which effectively controls the deformation of the pipeline assembly 200. At the same time, the outer side of the outer pipe layer 100 is subjected to the pressure of other substances in the oil field, such as soil, and the support belt is an important structure to support the outer pipe layer 100 from collapsing;

[0041] 2. When sand burial occurs, the pipe assembly 200 needs to be removed.

[0042] When sand burial occurs, the pipeline assembly 200 needs to be extracted. If the pipeline is not recovered in time, the pipeline will be buried and squeezed by gravel. The pipeline assembly 200 will be deformed or the outer pipe layer 100 will exceed the support limit. The pipeline assembly 200 cannot be used for oil extraction. At the same time, it is also a big problem to recover the pipeline assembly 200 from the sand burial interface.

[0043] During the process of recovering the pipeline, since the sand burial will gradually extend from the bottom of the pipeline, the bottom of the outer tube layer 100 will first contact the gravel, and the outer tube layer 100 can no longer be smoothly pulled out from the well. It is necessary to lift the top of the pipeline component 200 and pull the pipeline component 200 out of the outer tube layer 100 through a spiral path. When the sand burial occurs, the rolling element 510 supports the outer tube layer 100 so that it will not be greatly deformed, effectively ensuring the separation of the pipeline component 200, and the subsequent outer tube layer 100 is independently taken out or crushed in the well;

[0044] The pipe assembly 200 is rotated and pulled upward along the spiral path, wherein the rolling element 510 between the inner support layer 530 and the outer tube layer 100 moves along the groove direction of the rolling groove 520. During the movement, the carrying groove 513 on the rolling column 511 continuously carries out the grease from the rolling groove 520. The grease is continuously rolled and carried by the rolling column 511, and the grease is thrown out by the centrifugal force generated during rolling, so that the grease adheres to the inner wall of the outer tube layer 100 and the outer wall of the inner support layer 530. After the grease is added, the frictional heat generated by the rolling friction is lower than the heat generated by the sliding friction, so the temperature rise rate of the pipe wall is slower. At the same time, the continuous mixing and addition of the grease and the mixing of the heated grease can effectively transfer the heat to the bottom of the rolling groove 520, accelerate the heat dissipation, and at the same time, the grease will not fail under high temperature conditions due to the continuous frictional heat generated by the grease.

[0045] It is worth noting that, as the outer tube layer 100 is continuously squeezed, the notch end of its rolling groove 520 gradually expands, and a limiting flange may be provided at the end of the column shaft 512, so that the column shaft 512 is always located in the support portion 110, that is, the column shaft 512 is still located in the groove wall of the rolling groove 520 when the notch expands. As the notch expands, the lubricating layer 120 in the groove wall will continue to approach the outer surface of the rolling column 511. During subsequent continuous rolling, the carrying groove 513 can continuously carry out part of the grease from the rolling groove 520, continuously renewing the lubricating layer 120 between the outer tube layer 100 and the inner support layer 530, thereby playing an effective cooling and lubricating role, and ensuring the rapid and stable extraction of the pipeline assembly 200.

[0046] The above describes an embodiment of the present embodiment, but the present embodiment is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present embodiment, ordinary technicians in this field can also make many forms, all of which are within the protection of the present embodiment.

Claims

1. A high external pressure and high temperature resistant composite continuous pipe, comprising an outer pipe layer (100), a pipe assembly (200) arranged in the outer pipe layer (100), and a centralizer (300) sleeved on the outer side of the outer pipe layer (100), characterized in that: A plurality of support rings (400) are sleeved on the outer side of the pipeline component (200); the plurality of support rings (400) are spaced and distributed on the outer wall of the pipeline component (200); a rolling component (500) is disposed between the inner side of the pipeline component (200) and the outer side of the pipeline component (200); the pipeline component (200) moves from the inner side of the outer tube layer (100) along the axis of the pipeline component (200) via the rolling component (500); A spiral rolling groove (520) is provided on the inner side of the outer tube layer (100); the rolling component (500) moves along the groove direction of the rolling groove (520); a lubricating layer (120) is provided on the inner side of the rolling groove (520); a carrying groove (513) is provided on the outer side of the rolling component (500); when the rolling component (500) moves along the groove direction of the rolling groove (520), the rolling component (500) transfers the lubricating layer (120) from the rolling groove (520) to the outer wall of the pipe component (200) or the inner wall of the outer tube layer (100) through the carrying groove (513); The rolling assembly (500) comprises a rolling element (510), and two ends of the rolling element (510) are respectively arranged at two side gaps between opposite sides of the pipeline assembly (200) and the outer tube layer (100); The rolling element (510) comprises a rolling column (511) and a column shaft (512), wherein the column shaft (512) is arranged on the outer walls at both ends of the rolling column (511), and the column shaft (512) is installed on the inner wall of the outer tube layer (100); The carrying grooves (513) are distributed on the outer wall of the rolling column (511), and the vertically upward position of the rolling column (511) where the carrying grooves (513) are provided is located above the lubricating layer (120).

2. The high external pressure and high temperature resistant composite coiled tube according to claim 1, characterized in that: The pipeline component (200) comprises an inner lining layer (210), a reinforcement layer (220) and a protective layer (230); the reinforcement layer (220) is arranged between the inner lining layer (210) and the protective layer (230), and the protective layer (230) is arranged on an outer wall of the pipeline component (200) on one side close to the outer tube layer (100).

3. The high external pressure and high temperature resistant composite coiled tube according to claim 2, characterized in that: An inner support layer (530) is provided on the outer side of the pipeline assembly (200), and the inner support layer (530) is provided with a support groove that is rollingly matched with the rolling assembly (500).

4. The high external pressure and high temperature resistant composite coiled tube according to claim 3, characterized in that: The inner lining layer (210) is made of high temperature resistant cross-linked polyethylene, the reinforcing layer (220) is made of glass fiber pre-impregnated polyethylene, and the protective layer (230) and the outer tube layer (100) are both made of polyethylene.

5. The high external pressure and high temperature resistant composite coiled tube according to claim 4, characterized in that: The support ring (400) is made of high-strength carbon steel.

6. The high external pressure and high temperature resistant composite coiled tube according to claim 5, characterized in that: The centralizer (300) comprises a ring body (310) and side support plates (320), wherein the side support plates (320) are distributed in an annular shape on the outer wall of the ring body (310).

7. The high external pressure and high temperature resistant composite coiled tube according to claim 6, characterized in that: The inner wall of the ring body (310) is provided with pressing parts (330) at both end surfaces close to the ring body (310), and the position where the centralizer (300) is fixed on the outer side of the outer pipe layer (100) corresponds to the position where the support ring (400) is fixed on the pipeline assembly (200).

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