Underground heat-preservation super-heat-conduction oil pipe
By setting aluminum pipes in the oil pipes during oil field oil production, and setting the space between the casing and oil pipes, the problem of wax formation when crude oil rises to the ground is solved, and the efficiency and cost-effectiveness of crude oil mining are improved.
Patent Information
- Application Number
- CN202422205684.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-09
- Publication Date
- 2025-05-30
- Estimated Expiration
- 2034-09-09
AI Technical Summary
During the oil field oil production process, the temperature of crude oil is easily waxed due to the decrease in temperature during the oil field, which hinders the increase of the suction rod and increases the difficulty of crude oil extraction.
A downhole insulation superconducting thermal oil pipe is adopted. By setting an aluminum pipe in the oil pipe to conduct heat, the high-temperature heat at the bottom of the well is transmitted to the above oil well, and the casing is spaced between the oil pipe to reduce heat loss and avoid crude oil wax formation.
It effectively reduces the wax formation above the oil well, avoids obstacles when the suction rod lifts crude oil, and improves the efficiency and cost-effectiveness of crude oil mining.
Smart Images
Figure CN222924432U_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of oil extraction tools, and particularly relates to a downhole heat-preserving super heat-conducting oil pipe. Background Art
[0002] The oil pipe and the sucker rod are two important indispensable components in the process of oilfield oil production. The oil pipe is the channel for crude oil flow, and the sucker rod is located in the oil pipe and used to lift the underground crude oil to the ground. The depth of the oil well is relatively deep, generally reaching several thousand meters. In the exploitation of crude oil, the temperature of the underground oil layer is relatively high, and the crude oil has good fluidity in the underground oil layer. However, as the crude oil is lifted to the ground by the sucker rod, the temperature of the geological layer will gradually decrease. When the crude oil rises from the bottom of the well to about seven or eight hundred meters from the ground, the external temperature reaches thirty or forty degrees Celsius. The external temperature is directly transmitted to the crude oil in the oil pipe through the casing located outside the oil pipe, which will cause wax deposition in the oil pipe and block the oil pipe channel, making it impossible for the sucker rod to lift, resulting in great difficulty in the exploitation of crude oil.
[0003] In order to reduce the occurrence of wax deposition in crude oil, currently, a heating cable is set inside the sucker rod to electrically heat the inside of the oil pipe. The structure of the electric heating requires an external power supply and a control structure, which is not only very complex and difficult to operate. At the same time, the power consumption is very large, and because there is light oil in the petroleum, the light oil will vaporize when heated, and the vaporization will absorb the heat inside the oil pipe, resulting in the temperature inside the oil pipe not being able to increase or even being lower. The method of electric heating cannot completely solve the problem of wax deposition in the oil pipe and cannot fundamentally solve the economic problem of reducing the cost of crude oil exploitation. Content of the Utility Model
[0004] We hope to provide a downhole heat-preserving super heat-conducting oil pipe that can keep the temperature of the crude oil in the oil pipe unchanged with the geological height, so as to avoid the situation where the crude oil cannot be normally exploited due to wax deposition.
[0005] A downhole heat-preserving super heat-conducting oil pipe provided by this application adopts the following technical solutions:
[0006] A downhole heat-preserving super heat-conducting oil pipe includes: an oil pipe and an aluminum pipe inserted into the oil pipe. One end of the aluminum pipe is flush with one end of the oil pipe, and the other end of the aluminum pipe is shorter than the other end of the oil pipe;
[0007] A casing is sleeved outside the oil pipe, and there is a gap between them.
[0008] By adopting the above technical solution, since the aluminum pipe has good thermal conductivity, the aluminum pipe can conduct the high-temperature heat at the bottom of the well to above the oil well, reduce the wax formation above the oil well, and avoid hindering the sucker rod from lifting the crude oil to the ground. In addition, since the casing is in direct contact with the external and upper low-temperature geological layer, setting the tubing and the casing at intervals can reduce the heat exchange between the low temperature in the upper geological layer and the high temperature in the aluminum pipe, further reducing the heat loss in the aluminum pipe and avoiding the wax formation of the crude oil.
[0009] Optionally, a coupling is provided at the connection of two adjacent said tubing, and a centralizer made of insulating material is sleeved on the coupling, and the centralizer forms an interval between the tubing and the casing.
[0010] By adopting the above technical solution, setting the centralizer can make the tubing centered in the casing and prevent the two from contacting. The centralizer is made of insulating material, which can avoid the heat exchange of the low temperature in the geological layer outside the casing to the tubing, and keep the temperature inside the tubing from leaking out as much as possible.
[0011] Optionally, another centralizer is provided in the middle of the tubing, and each centralizer includes two upper and lower crosses.
[0012] By adopting the above technical solution, since the tubing is relatively long, in order to avoid the tubing itself from possibly contacting the casing, a centralizer is also provided in the middle of the tubing to further form an interval between the tubing and the casing. The cross-shaped centralizer can increase the upper and lower contact degrees with the casing and improve the function of the centralizer to form an interval.
[0013] Optionally, reduced tapered portions are formed at the facing positions of two adjacent said tubing, external threads are formed on the outer walls of the tapered portions, two mutually communicating inner tapered openings are provided inside the coupling, and internal threads are provided on both of the inner tapered openings.
[0014] By adopting the above technical solution, the tapered portion on the tubing is threadedly connected to the inner tapered opening in the coupling, so that the connection surface forms a wedge surface, which can increase the compression degree and the contact surface size of the two contact surfaces during the rotation of the thread.
[0015] Optionally, a heat insulation layer is provided on the outer wall of the tubing.
[0016] By adopting the above technical solution, the heat insulation layer can further enhance the heat preservation performance of the tubing, maintain the temperature inside the tubing unchanged, and avoid the occurrence of wax formation.
[0017] Optionally, the upper end of the aluminum pipe is flush with the upper end of the tubing, and the lower end of the aluminum pipe is shorter than the lower end of the tubing.
[0018] By adopting the above technical solution, the same end where the aluminum pipe and the oil pipe are located is somewhat shorter, which can prevent the aluminum pipe from coming into contact with high-temperature crude oil and expanding and contracting due to heat, thus protruding from the oil pipe.
[0019] Optionally, the distance between the lower end of the aluminum pipe and the lower end of the oil pipe is 15 cm to 25 cm.
[0020] By adopting the above technical solution, the bottom end of the aluminum pipe is about 20 cm shorter than the bottom end of the oil pipe. The temperature at the bottom end of the aluminum pipe is not much different from the temperature at the bottom of the oil pipe, which will not affect the upward heat conduction of the aluminum pipe. At the same time, it leaves a length margin for the aluminum pipe to expand and contract downward when heated.
[0021] Optionally, the materials of the oil pipe and the casing are alloy steel.
[0022] In summary, the present application includes at least one of the following beneficial technical effects: On the one hand, the aluminum pipe has good heat conductivity. Setting the aluminum pipe inside the oil pipe can conduct the high-temperature heat at the bottom of the well from the bottom of the oil well to the upper part of the oil well, reducing the wax formation at a depth of seven or eight hundred meters or more from the ground, and avoiding the phenomenon of hindering the sucker rod from lifting the crude oil to the ground. On the other hand, since the casing directly contacts the low-temperature geological layer above, setting the oil pipe and the casing at intervals to form a certain space can reduce the heat exchange between the low temperature in the upper geological layer and the high temperature in the aluminum pipe, further reducing the heat loss in the aluminum pipe. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 is a schematic cross-sectional structure diagram of an underground heat-insulating and super heat-conducting oil pipe embodying the present application;
[0024] Figure 2 is a top view of an underground heat-insulating and super heat-conducting oil pipe embodying the present application;
[0025] Figure 3 is a schematic structure diagram of an underground heat-insulating and super heat-conducting oil pipe after hiding the casing embodying the present application.
[0026] Description of the reference numerals:
[0027] 1. Oil pipe; 11. Tapered mouth part; 2. Aluminum pipe; 3. Casing; 4. Coupling; 41. Inner tapered mouth; 5. Centralizer; 50. Cross; 51. Leg; 52. Notch; 53. Flow channel; 6. Heat-insulating layer. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0028] The following is a further detailed description of the present application in conjunction with the attached Figures 1 - 3 for the present application.
[0029] The embodiment of the present application discloses a method for actively controlling the hardening time of the steel strand slow bond.
[0030] Please refer to Figure 1 、Figure 2 and Figure 3 Figure 3 , a downhole heat-insulating super heat-conducting oil pipe, includes a long strip-shaped and hollow oil pipe 1. Each oil pipe 1 is nearly 9 meters long. Multiple oil pipes 1 are spliced into a circulation channel for crude oil to be used for the transportation of crude oil. A sucker rod is arranged inside the oil pipe 1, and a casing 3 is sleeved outside. A centralizer 5 is arranged between the two. On the one hand, it makes the oil pipe 1 centered in the casing 3, and on the other hand, it makes the oil pipe 1 and the casing 3 not in contact with each other.
[0031] The casing 3 is in direct contact with the geological layer and is used for supporting the geological layer. Setting the centralizer 5 can make the oil pipe 1 and the casing 3 not in contact with each other, thereby reducing the conduction of low temperature in the geological layer to the oil pipe 1 by the casing 3, reducing the wax formation of the crude oil in the oil pipe 1, and avoiding hindering the lifting channel of the sucker rod. The shapes of the oil pipe 1 and the casing 3 are set according to the shape of the wellbore. The materials of both the oil pipe 1 and the casing 3 are alloy steel materials.
[0032] Since when crude oil is mined from the downhole, the downhole temperature is relatively high and the temperature of the crude oil located downhole is also relatively high. In order to keep the temperature of the downhole crude oil constant without losing temperature, and even keep it when the crude oil rises to seven or eight hundred meters from the ground, an aluminum pipe 2 with good heat-conducting performance is inserted inside each oil pipe 1, which can conduct the heat at the bottom of the well to the upper part. The aluminum pipe 2 is also hollow tubular and closely adheres to the inner wall of the oil pipe 1. The aluminum pipe 2 can be embedded into the oil pipe 1 through a hydraulic press. In short, any existing method that can sleeve two pipes together can be used, and it will not be elaborated here.
[0033] One end of the aluminum pipe 2 and one end of the oil pipe 1 are flush and fixed together with adhesive glue. In order to prevent the aluminum pipe 2 from contacting the high-temperature crude oil and expanding and contracting to extend out of the oil pipe 1, the other end of the aluminum pipe 2 is shorter than the other end of the oil pipe 1. Therefore, when the aluminum pipe 2 expands due to high temperature, it can basically only elongate vertically. Since one end of the aluminum pipe 2 is shorter than one end of the oil pipe 1 before installation, the elongated aluminum pipe 2 will not be longer than the oil pipe 1 and extend out of the oil pipe 1. And the end parts of the aluminum pipe 2 and the oil pipe 1 bonded by glue have relatively small deformation and will not extend out of the oil pipe 1 either.
[0034] The end parts of the aluminum pipe 2 and the oil pipe 1 bonded by glue can be located at the upper end or the lower end. When the bonded end is at the lower part, the aluminum pipe 2 can directly contact the high-temperature oil at the bottom layer, directly conduct the temperature, and the elongated section after expansion will occur at the upper end of each aluminum pipe 2.
[0035] When the bonded end is at the upper part, the upper end of the oil pipe 1 also has an aluminum pipe 2 and can conduct heat in time. The distance between the lower end of the aluminum pipe 2 and the lower end of the oil pipe 1 is 20 cm to 30 cm. The oil temperature here is also relatively high, and the aluminum pipe 2 can also better contact the high-temperature oil. The elongated section after expansion occurs at the lower end of the aluminum pipe 2, so that the whole can continuously conduct the temperature.
[0036] To prevent the heat inside the aluminum pipe 2 from dissipating to the outside of the oil pipe 1 and also to prevent the low temperature in the geological formation outside the casing 3 from exchanging heat with the oil pipe 1, a heat insulation layer 6 is provided on the outer wall of the oil pipe 1, which can further enhance the heat preservation performance of the oil pipe 1. The heat insulation layer 6 can be provided on the outer wall of the oil pipe 1 by coating. The specific material can be asbestos composite, heat preservation paint, etc.
[0037] A coupling 4 is provided at the connection of two adjacent oil pipes 1. Gradually reducing tapered portions 11 are formed at the facing positions of two adjacent oil pipes 1. External threads are formed on the outer wall of the tapered portion 11, and two mutually communicating internal tapered openings 41 are provided inside the coupling 4. Internal threads are provided on the internal tapered opening 41.
[0038] When installing two oil pipes 1, first thread-connect the tapered portion 11 of one oil pipe 1 with one of the internal tapered openings 41 in the coupling 4. The contact portion between the tapered portion 11 and one internal tapered opening 41 forms a wedge-shaped contact surface, which can increase the sealing performance between the two. Then thread the tapered portion 11 of the other oil pipe 1 into the other internal tapered opening 41 in the coupling 4. A wedge-shaped contact surface is also formed between the two, which can also increase the tightness and the size of the contact surface between the two, thereby increasing the sealing performance.
[0039] An aligner 5 made of insulating material is fixedly sleeved on the coupling 4. The aligner 5 forms a spaced space between the oil pipe 1 and the casing 3. Since the oil pipe 1 is relatively long, in order to prevent each oil pipe 1 from possibly contacting the casing 3 at a certain curvature, an aligner 5 is also fixedly connected to the middle of the oil pipe 1.
[0040] Each aligner 5 includes two upper and lower crosses 50. The material of the aligner 5 can be insulating materials such as nylon composite. Since the aligner 5 indirectly connects the oil pipe 1 and the casing 3, setting the aligner to an insulating material can further prevent the low temperature in the geological formation outside the casing 3 from exchanging heat with the oil pipe 1 and also reduce the heat in the aluminum pipe 2 from being conducted to the outside of the casing 3 through the oil pipe 1.
[0041] A notch 52 is formed between the upper and lower adjacent legs 51 of the two crosses 50 of each aligner. A flow passage 53 is also formed between the adjacent legs 51 of the same cross 50. Since the oil in the oil layer will also enter the flow passage 53 due to pressure, the liquid level height of the oil can be measured. Setting the notch 52 can further make the oil flow more smoothly.
[0042] The above are all the preferred embodiments of this application. The protection scope of this application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.
Claims
1. A downhole thermal insulation superconducting oil pipe, characterized in that: It comprises an oil pipe (1) and an aluminum pipe (2) inserted into the oil pipe (1), one end of the aluminum pipe (2) is flush with one end of the oil pipe (1), and the other end of the aluminum pipe (2) is shorter than the other end of the oil pipe (1); The oil pipe (1) is externally sleeved with a casing (3), with the casing (3) being spaced apart therebetween.
2. The underground thermal insulation superconducting oil pipe according to claim 1 is characterized in that: A coupling (4) is provided at the connection point between two adjacent oil pipes (1), and a centralizer (5) made of insulating material is sleeved on the coupling (4). The centralizer (5) forms a gap between the oil pipe (1) and the casing (3).
3. The underground thermal insulation superconducting oil pipe according to claim 2 is characterized in that: Another centralizer (5) is provided in the middle of the oil pipe (1), and each centralizer (5) comprises two upper and lower crosses (50).
4. The underground thermal insulation superconducting oil pipe according to claim 2 is characterized in that: A tapered conical opening (11) is formed at the opposite positions of two adjacent oil pipes (1), and an external thread is formed on the outer wall of each of the conical openings (11). Two mutually interpenetrating internal conical openings (41) are formed inside the coupling (4), and both of the two internal conical openings (41) are provided with internal threads.
5. The underground thermal insulation superconducting oil pipe according to claim 1, characterized in that: A heat insulation layer (6) is provided on the outer wall of the oil pipe (1).
6. The underground thermal insulation superconducting oil pipe according to claim 1, characterized in that: The upper end of the aluminum tube (2) is flush with the upper end of the oil tube (1), and the lower end of the aluminum tube (2) is shorter than the lower end of the oil tube (1).
7. The underground thermal insulation superconducting oil pipe according to claim 6 is characterized in that: The distance between the lower end of the aluminum tube (2) and the lower end of the oil tube (1) is 15 cm to 25 cm.
8. The underground thermal insulation superconducting oil pipe according to claim 6, characterized in that: The oil pipe (1) and the casing (3) are made of alloy steel.