Pipeline core rope heat exchanger for ground cooling of drilling fluid

Abstract

The invention provides a pipeline core rope heat exchanger for ground cooling of drilling fluid, and belongs to the technical field of drilling engineering, the pipeline core rope heat exchanger comprises a pipe body and a heat exchange assembly, the pipe body comprises a pipe body inner cavity and a pipe body outer wall, the heat exchange assembly is arranged in the pipe body inner cavity, and a drilling fluid outlet is formed in the top of the pipe body inner cavity; a drilling fluid inlet is formed in the bottom of an inner cavity of the pipe body, a cooling liquid inlet and a cooling liquid outlet are formed in the two sides of the outer wall of the pipe body respectively, and a partition plate is arranged in the inner cavity of the pipe body. The heat exchange assembly comprises a plurality of heat exchange pipes, the heat exchange pipes are evenly arranged in an inner cavity of a pipe body, each heat exchange pipe comprises a core rope, a spiral fin and a heat exchange pipe inner wall, the spiral fins are arranged on the peripheries of the core ropes in a sleeving mode, the core ropes and the spiral fins are of an integrated structure, the two ends of each heat exchange pipe are fixedly connected with the spiral fins, and the spiral fins are connected with the heat exchange pipe inner walls. And a baffle plate is arranged between every two adjacent heat exchange tubes. It is guaranteed that fluid is fully cooled, and it can be guaranteed that fluid resistance is not too large; and the cost is low.

Description

Technical Field

[0001] The present invention relates to the technical field of drilling engineering, and particularly to a pipe core rope heat exchanger for cooling and temperature reduction of drilling fluid on the ground. Background Art

[0002] The cooling and temperature reduction of drilling fluid is a crucial link in drilling engineering. It not only provides necessary support for drilling operations but also plays multiple key functions throughout the drilling process. As the depth of oil and gas well development in China continues to increase, there will be more and more deep wells and ultra-deep wells, and the requirements for drilling fluid ground cooling and temperature reduction technology will also continue to improve. The main problem of drilling fluid ground cooling and temperature reduction technology lies in how to improve the cooling and temperature reduction efficiency of drilling fluid.

[0003] If the drilling fluid cannot be cooled and temperature-reduced in time, it often leads to many problems such as changes in the physical and chemical properties of the drilling fluid, affecting fluidity and viscosity, lack of downhole fluid, and instability of the wellbore wall. The heat transfer efficiency of shell-and-tube heat exchangers is often limited by their design and materials: the fluid flow rate in straight tubes is too fast, and the time for the fluid to obtain temperature reduction is not sufficient. Due to the shape of the coiled pipes, the fluid resistance in the pipes is relatively large. Whether it is a straight tube or a coiled tube heat exchanger, its performance is limited by materials. Especially in high-temperature, high-pressure, or corrosive media, the selection of materials is crucial; the existing straight tube and coiled tube heat exchangers all have the problem of insufficient energy efficiency optimization, often failing to make full use of fluid dynamics and thermodynamics principles, resulting in low energy efficiency. Summary of the Invention

[0004] The purpose of the present invention is to provide a pipe core rope heat exchanger for cooling and temperature reduction of drilling fluid on the ground, which can not only ensure that the fluid is fully cooled, but also ensure that the fluid resistance is not too large, and at the same time, the cost is relatively low.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A pipe core rope heat exchanger for cooling and temperature reduction of drilling fluid on the ground, comprising a pipe body and a heat exchange component, characterized in that:

[0007] The pipe body includes a pipe inner cavity and a pipe outer wall. The heat exchange component is arranged in the pipe inner cavity. A drilling fluid outlet is arranged at the top of the pipe inner cavity, a drilling fluid inlet is arranged at the bottom of the pipe inner cavity, a coolant inlet and a coolant outlet are respectively arranged on both sides of the pipe outer wall, and a partition is arranged in the pipe inner cavity.

[0008] The heat exchange component includes a plurality of heat exchange tubes, which are uniformly arranged in the inner cavity of the tube. The heat exchange tube includes a core rope, spiral fins, and the inner wall of the heat exchange tube. The spiral fins are sleeved around the periphery of the core rope. The core rope and the spiral fins are of an integral structure. Both ends of the heat exchange tube are fixedly connected to the spiral fins, and the spiral fins are in contact with the inner wall of the heat exchange tube. A baffle is arranged between each adjacent heat exchange tube.

[0009] Further, the diameter of the outermost circle of the spiral fins is the same as the diameter of the inner wall of the heat exchange tube.

[0010] Further, both ends of the heat exchange tube are connected to the spiral fins by welding.

[0011] Further, the pitch of the spiral fins is 0.5 to 2 times the diameter of the inner wall of the heat exchange tube, the spiral angle of the spiral fins is 30° to 60°, and the number of blades of the spiral fins is 3 to 6.

[0012] Further, the distance between each baffle is 20% to 50% of the inner diameter of the tube, and the angles of each baffle are the same.

[0013] Further, the angle of the baffle is 30° or 45° or 90°.

[0014] Further, the baffles are arranged alternately to form a "Z"-shaped flow path.

[0015] Further, the gap between the top of the partition plate and the top of the tube is adjusted according to the diameter of the tube, and the range of the gap is 5% to 15% of the diameter of the tube.

[0016] Further, the baffle and the partition plate are connected by welding or screws.

[0017] Further, the core rope is made of low-carbon steel.

[0018] Advantages of the present invention:

[0019] 1. Compared with the ordinary straight pipe structure, the structure adopted by the present invention can make the fluid stay in the pipeline for a longer time. Compared with the ordinary coiled pipe structure, the structure adopted by the present invention can reduce the resistance of the fluid.

[0020] 2. The spiral fins can cause the drilling fluid in the tube to form vortices during flow, making full use of hydrodynamics, increasing the surging of the fluid in the pipeline, making the heat exchange more uniform, and prolonging the residence time of the fluid in the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a structural cross-sectional view of the present invention;

[0022] Figure 2 This is an enlarged view of the structure of the heat exchange tube in the present invention;

[0023] In the figure: 1. Inner cavity of the tube;

[0024] 2. Heat exchange tube; 21. Core rope; 22. Spiral fin; 23. Inner wall of the heat exchange tube;

[0025] 3. Drilling fluid outlet;

[0026] 4. Drilling fluid inlet;

[0027] 5. Coolant inlet;

[0028] 6. Coolant outlet;

[0029] 7. Baffle plate;

[0030] 8. Partition plate. Detailed implementation manners

[0031] To make the objectives, technical solutions and advantages of the implementation manners of the present invention clearer, the technical solutions in the implementation manners of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the implementation manners of the present invention. Apparently, the described implementation manners are part rather than all of the implementation manners of the present invention. Based on the implementation manners in the present invention, all other implementation manners obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention. Therefore, the following detailed description of the implementation manners of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention claimed, but merely represents selected implementation manners of the present invention.

[0032] As shown in Figure 1 and Figure 2 , a pipe core rope heat exchanger for cooling and temperature reduction of drilling fluid on the ground includes a pipe body and a heat exchange assembly.

[0033] The pipe body includes an inner cavity 1 of the pipe and an outer wall of the pipe. The heat exchange assembly is arranged in the inner cavity 1 of the pipe. A drilling fluid outlet 3 is arranged at the top of the inner cavity 1 of the pipe, a drilling fluid inlet 4 is arranged at the bottom of the inner cavity 1 of the pipe, a coolant inlet 5 and a coolant outlet 6 are respectively arranged on both sides of the outer wall of the pipe, and a partition plate 8 is arranged in the inner cavity 1 of the pipe.

[0034] The heat exchange assembly includes a plurality of heat exchange tubes 2. The plurality of heat exchange tubes 2 are uniformly arranged in the inner cavity 1 of the pipe. The heat exchange tube 2 includes a core rope 21, a spiral fin 22 and an inner wall 23 of the heat exchange tube. The spiral fin 22 is sleeved on the periphery of the core rope 21. The core rope 21 and the spiral fin 22 are of an integral structure. Both ends of the heat exchange tube 2 are fixedly connected to the spiral fin 22. The spiral fin 22 is in contact with the inner wall 23 of the heat exchange tube. A baffle plate 7 is arranged between each adjacent heat exchange tube 2.

[0035] The spiral fins are conducive to the formation of vortices of the drilling fluid in the heat exchange tubes, increasing the surging of the fluid. The material for making the spiral fins 22 is selected as a material with good ductility.

[0036] As a preferred embodiment of the present invention, the diameter of the outermost circle of the spiral fins 22 is the same as the diameter of the inner wall 23 of the heat exchange tube. The spiral fins 22 on the core rope 21 are in direct contact with the inner wall 23 of the heat exchange tube, which can ensure that the temperature of the core rope 21 is approximately the same as the temperature of the coolant, so as to facilitate the core rope 21 and the spiral fins 22 to absorb the temperature of the drilling fluid. The presence of the spiral fins 22 also increases the heat dissipation area.

[0037] As a preferred embodiment of the present invention, both ends of the heat exchange tube 2 are welded to the spiral fins 22, thereby fixing the position of the core rope 21 in the heat exchange tube 2.

[0038] As a preferred embodiment of the present invention, the pitch of the spiral fins 22 is 0.5 to 2 times the diameter of the inner wall 23 of the heat exchange tube, the spiral angle of the spiral fins 22 is 30° to 60°, and the number of blades of the spiral fins 22 is 3 to 6; such a setting can ensure that the drilling fluid forms vortices in the pipeline while the fluid resistance is not too large.

[0039] As a preferred embodiment of the present invention, the distance between each baffle 7 is 20% to 50% of the inner diameter of the pipe body, and the angles of each baffle 7 are kept consistent.

[0040] As a preferred embodiment of the present invention, the angle of the baffle 7 is 30° or 45° or 90°.

[0041] As a preferred embodiment of the present invention, the baffles 7 are arranged alternately to form a "Z"-shaped flow path, which can enhance turbulence.

[0042] As a preferred embodiment of the present invention, the gap between the top of the partition plate 8 and the top of the pipe body is adjusted according to the diameter of the pipe body, and the range of the gap is 5% to 15% of the diameter of the pipe body. For a pipe body with a smaller diameter, the gap is 5% to 10%. For a pipe body with a larger diameter, the gap is 10% to 15%.

[0043] As a preferred embodiment of the present invention, the baffles 7 and the partition plates 8 are connected by welding or screws. Welding has high strength and good airtightness, and screw connection is used for occasions that need to be frequently installed and disassembled.

[0044] As a preferred embodiment of the present invention, the core rope 21 is made of low-carbon steel. Selecting a material with better thermal conductivity can facilitate the cooling of the drilling fluid. There are three materials available for selection: low-carbon steel, copper, aluminum, and magnesium alloy. Different materials are selected to make the core rope structure according to the acidity and alkalinity and corrosion intensity of the drilling fluid. In an acidic environment, copper and zinc should be avoided; magnesium alloy should be avoided in drilling fluid with strong corrosion; low-carbon steel can be used in most environments, but attention should be paid to the anti-rust treatment of low-carbon steel.

[0045] As a preferred embodiment of the present invention, the pipe body is a circular pipe.

[0046] The working process of this device:

[0047] As Figure 1 shown, the drilling fluid enters the heat exchanger from the drilling fluid inlet 4, and flows out of the heat exchanger from the drilling fluid outlet 3 after cooling down; the coolant enters the heat exchanger from the coolant inlet 5, and circulates in the heat exchanger in one circle along the arrow direction and then flows out of the heat exchanger from the coolant outlet 6.

[0048] After the drilling fluid enters the heat transfer tube 2 from the drilling fluid inlet 4, the drilling fluid will contact the spiral fins 22 and obtain a better cooling effect. At the same time, the structure of the spiral fins 22 can make the drilling fluid form a vortex in the heat transfer tube 2, with strong surging, and the heat exchange of the drilling fluid is more uniform.

[0049] The above are only preferred embodiments of the present invention and are not used to limit the present invention. Those skilled in the art can still adjust the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features. Therefore, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and its equivalent technologies, the present invention also intends to include these changes and variations.

Claims

1. A pipe core rope heat exchanger for cooling drilling fluid on the ground, comprising a pipe body and a heat exchange component, characterized in that: The tube body comprises an inner tube cavity (1) and an outer tube wall, the heat exchange component is arranged in the inner tube cavity (1), a drilling fluid outlet (3) is arranged at the top of the inner tube cavity (1), a drilling fluid inlet (4) is arranged at the bottom of the inner tube cavity (1), a cooling liquid inlet (5) and a cooling liquid outlet (6) are arranged on both sides of the outer tube wall respectively, and a partition (8) is arranged in the inner tube cavity (1); The heat exchange assembly comprises a plurality of heat exchange tubes (2), the plurality of heat exchange tubes (2) being evenly arranged in an inner cavity (1) of a tube body, the heat exchange tube (2) comprising a core rope (21), a spiral fin (22) and an inner wall (23) of the heat exchange tube, the spiral fin (22) being sleeved on the outer periphery of the core rope (21), the core rope (21) and the spiral fin (22) being of an integrated structure, the two ends of the heat exchange tube (2) being fixedly connected to the spiral fin (22), the spiral fin (22) being connected to the inner wall (23) of the heat exchange tube, and a baffle (7) being arranged between each adjacent heat exchange tube (2).

2. A pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 1, characterized in that: The outermost diameter of the spiral fin (22) is the same as the diameter of the inner wall (23) of the heat exchange tube.

3. The pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 2, characterized in that: Both ends of the heat exchange tube (2) are connected to the spiral fins (22) by welding.

4. A pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 3, characterized in that: The pitch of the spiral fin (22) is 0.5 to 2 times the diameter of the inner wall (23) of the heat exchange tube, the spiral angle of the spiral fin (22) is 30° to 60°, and the number of blades of the spiral fin (22) is 3 to 6.

5. The pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 4, characterized in that: The spacing between each of the baffles (7) is 20% to 50% of the inner diameter of the tube body, and the angle of each of the baffles (7) remains consistent.

6. The pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 5, characterized in that: The angle of the baffle (7) is 30°, 45° or 90°.

7. A pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 6, characterized in that: The baffles (7) are arranged alternately to form a "Z"-shaped flow path.

8. The pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 7, characterized in that: The gap between the top of the partition (8) and the top of the tube body is adjusted according to the diameter of the tube body, and the range of the gap is 5% to 15% of the diameter of the tube body.

9. A pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 8, characterized in that: The baffle (7) and the partition (8) are connected by welding or screws.

10. A pipe core rope heat exchanger for ground cooling of drilling fluid according to claim 9, characterized in that: The core rope (21) is made of low carbon steel.

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