A tubing electric heating wax removal and blockage removal device and a blockage removal process

Abstract

The present application belongs to the technical field of oil well tubing plugging, and discloses a tubing electric heating wax removal and plugging removal device and a plugging removal process. The device comprises a cable, a crawling arm, a motor, a hollow rod, a telescopic scraper, a melting agent storage box, a rotating ring, a hollow cavity heating body, a heating baffle, a heating rod, a telescopic supporting rod, a resistance wire, a steel pipe, a heat insulation layer, an insulating material and a heating head. The device can realize faster and more thorough plugging removal efficiency, and can guarantee the oil well exploitation benefit.

Description

Technical Field

[0001] This invention belongs to the field of oil well tubing blockage technology, specifically relating to an electric heating dewaxing and unblocking device and process for tubing. Background Technology

[0002] Although oilfields implement wax prevention and removal measures in routine maintenance and management of oil wells during crude oil extraction, wax deposition remains an unavoidable problem. During extraction, the release and expansion of molten gases lowers the temperature of waxy crude oil. When the temperature falls below the wax precipitation point, wax crystals precipitate and continuously deposit in the formation, tubing, and downhole equipment. Wax deposition in the formation reduces permeability, lowers oil recovery, and can even clog the oil-bearing layer. Wax deposition in tubing increases crude oil viscosity, increases resistance, reduces well productivity, increases operating costs, and can even clog surface pipelines. Simultaneously, in production wells, the mixture of oil sludge and paraffin wax within the tubing narrows the passage, affecting daily oil production and testing operations.

[0003] Currently, the commonly used methods for wax removal and oil removal are mechanical wax removal and thermal wax removal. Mechanical wax removal is simple, easy, and low-cost, but due to the limited space at the bottom of the well and the limitations of mechanical equipment, it is often ineffective in areas with high hardness or where the tubing is blocked. Furthermore, because the deposited wax is hard, easily damaged scrapers and scraped wax chunks tend to settle to the bottom of the wellbore, causing wellbore blockage. Thermal wax removal is simple to operate and fast-acting, but inaccurate assessment of the degree of wax buildup in the oil well leads to unreasonable hot washing cycles and parameters, resulting in poor wax removal, low thermal efficiency, and oil layer contamination. In actual production applications, often only one of these two methods is used for wax removal, resulting in less than ideal wax removal effects. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides an electric heating wax removal and unblocking device and process for oil wells. It combines mechanical wax removal with thermal wax removal, which solves the problem of poor wax removal effect. The device can simultaneously melt and remove wax, effectively improving the efficiency of wax removal in oil wells, ensuring the benefits of oil well exploitation, and also improving the success rate of related logging.

[0005] The above-mentioned objective of this invention is achieved through the following technical solution: an electric heating dewaxing and unblocking device for oil pipes, comprising a cable, a crawling arm, a motor, a hollow rod, a retractable scraper, a solvent storage box, a rotating ring, a cavity heating body, a heating baffle, a heating rod, a retractable support rod, a resistance wire, a steel pipe, a heat insulation layer, and a heating head; wherein the cable is connected to the hollow rod, and the hollow rod is provided with the crawling arm, the motor, the solvent storage box, the rotating ring, and the retractable support rod in sequence from top to bottom; the rotating ring is provided with a retractable scraper, and a cavity heating body is provided at the bottom of the rotating ring; a heating baffle is installed at the bottom of the retractable support rod, and the periphery of the heating baffle is connected to the cavity heating body; a heating rod is provided at the bottom of the heating baffle.

[0006] Furthermore, the upper edge of the heating baffle is made of insulating material, and a resistance wire c is wound around the center.

[0007] Furthermore, the main body of the cavity heating element is made of insulating material, a resistance wire a is wrapped around the main body of the cavity heating element, a steel pipe is provided on the outer wall, a heat insulation layer is provided between the steel pipe and the main body of the cavity heating element, and a heating head a is installed at the bottom end of the cavity heating element.

[0008] Furthermore, the heating rod body is made of insulating material, a resistance wire b is wrapped around the heating rod body, and a heating head b is provided at the bottom end of the heating rod.

[0009] Furthermore, the insulating material used for the upper edge of the heating baffle, the main body of the cavity heating element, and the main body of the heating rod is talc or silica.

[0010] Furthermore, the resistance wires in the center of the heating baffle, on the main body of the cavity heating element, and on the main body of the heating rod are made of nickel-chromium heating alloy or iron-chromium-aluminum alloy.

[0011] Furthermore, the insulation layer material between the steel pipe and the cavity heating body is polyurethane.

[0012] Another object of the present invention is to protect the unblocking process of the above-mentioned oil pipe electric heating dewaxing and unblocking device, which includes the following steps:

[0013] (1) Connect the device on the ground;

[0014] (2) Lower the oil pipe electric heating test device into the oil pipe;

[0015] (3) Lower the instrument to the blockage location, lift it up 5-10 meters, open the crawling arm and the retractable scraper, and spread the crawling arm and the retractable scraper to fit tightly against the inner wall of the pipe.

[0016] (4) When the motor is turned on, the retractable scraper and the cavity heating body rotate and heat. The retractable scraper scrapes away the residual blockage on the inner wall of the pipe, and the cavity heating body rotates to unblock it. The crawler arm pushes the cavity heating body downward. If the thickness at the obstruction point is less than the height of the heating cavity, the instrument is slowly lowered, and the blockage is unblocked through bottom rotation and heating. If the thickness at the obstruction point is greater than the height of the heating cavity, and the viscosity of the blockage is low, the electric heating rod is released to heat the oil and wax in the heating cavity. If the viscosity of the blockage is high, the electric heating rod is released to heat the oil and wax in the heating cavity, and other auxiliary agents such as melting agents or viscosity reducers in the device are released. If the viscosity of the blockage is too high, auxiliary agents can be injected into the well at the same time as the device is lowered to assist in unblocking. The heating speed can be controlled according to the power supply current. The waiting time can be set according to the situation. After the waiting time ends, the heating rod is retracted and the instrument is lifted.

[0017] (5) Lower the instrument again and repeat step (4) until the blockage is successfully cleared.

[0018] (6) Continue to lower the instrument 5-10 meters, stop working, retrieve the crawling arm and the retractable rotating scraper, turn off the power to stop heating, and lift the instrument back up.

[0019] The advantages of this invention compared to existing technologies are: the rotatable cavity heating element can achieve unblocking over a larger area; if the effect is not good, the heating rod set in the cavity formed by the inner wall of the cavity heating element and the heating baffle can achieve concentrated local unblocking; in addition, the spraying of melting agent and the retractable scraper can achieve faster and more thorough unblocking efficiency, thus ensuring the oil well exploitation benefits. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0021] Figure 1 This is a cross-sectional view of the oil pipe crawler arm of the oil pipe electric heating dewaxing and unblocking device of the present invention with the arm open.

[0022] Figure 2 This is a bottom view of the oil pipe electric heating dewaxing and unblocking device of the present invention with the lower oil pipe crawler arm open;

[0023] Figure 3 This is a cross-sectional view of the oil pipe electric heating dewaxing and unblocking device of the present invention before the oil pipe crawler arm is closed;

[0024] Figure 4 This is a bottom view of the oil pipe electric heating dewaxing and unblocking device of the present invention before the oil pipe crawler arm is lowered and closed;

[0025] Figure 5 This is a flow chart of the unblocking process of the oil pipe electric heating dewaxing and unblocking device of the present invention.

[0026] In the diagram: 1. Cable; 2. Oil pipe; 3. Crawler arm; 4. Motor; 5. Hollow rod; 6. Telescopic scraper; 7. Flux storage box; 8. Rotating ring; 9. Cavity heating element; 10. Heating baffle; 11. Heating rod; 12. Telescopic support rod; 91. Resistance wire a; 92. Steel pipe; 93. Insulation layer; 94. Main body of cavity heating element; 95. Heating head a; 101. Resistance wire c; 102. Upper edge of heating baffle; 111. Resistance wire b; 112. Main body of heating rod; 113. Heating head b. Detailed Implementation

[0027] The present invention is described in detail below through specific embodiments, but this does not limit the scope of protection of the present invention. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can all be obtained commercially.

[0028] like Figure 1 The diagram shows a schematic of an electric heating device for dewaxing and unblocking oil pipes according to the present invention. The device mainly consists of a cable 1, an oil pipe 2, a crawler arm 3, a motor 4, a hollow rod 5, a telescopic scraper 6, a flux storage box 7, a rotating ring 8, a cavity heating body 9, a heating baffle 10, a heating rod 11, and a telescopic support rod 12. The cavity heating body 9 consists of a resistance wire a91, a steel pipe 92, a heat insulation layer 93, a cavity heating body body 94, and a heating head a95. The heating baffle 10 consists of a resistance wire c101 and an upper edge 102 of the heating baffle. The heating rod 11 consists of a resistance wire b111, a heating rod body 112, and a heating head b113. Among them, steel pipe 92 is made of high-pressure seamless alloy steel pipe that is resistant to high pressure and does not deform; the main body 94 of the cavity heating element, the upper edge 102 of the heating baffle and the main body 112 of the heating rod are all made of crystalline magnesium oxide with thermal conductivity and insulation function, which plays a role in sealing and protecting the resistance wires a91, c101 and b111; the retractable scraper 6 is set with 4 scrapers at 90° to each other, the scraper is arc-shaped, made of smooth stainless steel, which does not wear the oil pipe and can be reused; the top of the rotating ring 8 is connected to the side wall of the retractable scraper and the bottom is connected to the cavity heating element 9. The rotating ring 8 drives the retractable scraper 6 and the cavity heating element 9 to rotate, and the rotation of the retractable scraper 6 realizes The cleaning of residual blockages on the inner wall of the oil pipe is accelerated by the rotation of the cavity heating element 9. The heating baffle 10 and the cavity heating element 9 form a cavity space. Due to the isolation layer 9.3 design on the outer wall of the cavity heating element 9, concentrated heating is achieved in the space, reducing heat loss. The heating rod 11 adopts a resistance structure, but it is not limited to this and can also be a liquid heating tube. Its top end is connected to the telescopic support rod 12. The telescopic support rod 12 controls the extension and retraction of the heating rod 11 in the hollow rod 5. The heating head a95 is hemispherical with a large working area, suitable for unblocking a large area. The heating head b113 is conical with a small working area, suitable for quickly unblocking a small area.

[0029] Example 1

[0030] (1) Connect the oil pipe electric heating test device and lower the device to the obstruction position (this position is wax or oil wax mixture), lift the device 5-10 meters, open the device crawling arm, fit it tightly against the inner wall of the pipe, support the device in the center, turn on the rotating telescopic scraper, turn on the bottom electric heating, and lower the device.

[0031] (2) The thickness at the obstruction point is less than the height of the heating chamber. The lowering speed is set to 0.5m / s. When the obstruction point is reached, the device is lowered slowly. The blockage can be cleared by rotating the bottom and heating.

[0032] (3) After lowering the device for another 5-10 meters, stop working, retrieve the crawling arm and the retractable rotating scraper, turn off the power to stop heating, and lift the retrieval device.

[0033] Example 2

[0034] (1) Connect the oil pipe electric heating test device and lower the device to the obstruction position (this position is wax or oil wax mixture), lift the device 5-10 meters, open the device crawling arm, fit it tightly against the inner wall of the pipe, support the device in the center, turn on the rotating telescopic scraper, turn on the bottom electric heating, and lower the device.

[0035] (2) When the thickness of the obstruction position is greater than the height of the heating chamber, the lowering speed is set to 0.5m / s. When the obstruction position is reached, the device is lowered slowly. At this time, the bottom rotates and is heated. When the second obstruction is reached 5-10 minutes later, the heat insulation baffle is opened and the electric heating rod is released to heat the oil, wax and other substances in the heating chamber. The heating speed can be controlled according to the power supply current. The heating rod is retracted in about 10-15 minutes and the device is lifted up.

[0036] (3) Lower the device again and repeat step (2) until the blockage is successfully cleared.

[0037] (4) After lowering the device for another 5-10 meters, stop working, retrieve the crawling arm and the retractable rotating scraper, turn off the power to stop heating, and lift the retrieval device.

[0038] Example 3

[0039] (1) Connect the oil pipe to the electric heating test and lower the device to the obstruction position (this position is where wax or oil wax mixture is formed). Raise the device 5-10 meters, open the device crawling arm, and support the device in the center by tightly fitting it to the inner wall of the pipe. Then turn on the rotating telescopic scraper, turn on the bottom electric heating, and lower the device.

[0040] (2) If the thickness at the obstruction point is greater than the height of the heating chamber and the viscosity is high, set the lowering speed to 0.5 m / s. When reaching the obstruction point, continue to lower the device slowly, rotating it at the bottom, heating it, and releasing the melting agent or viscosity reducer and other auxiliary agents inside the device. After the second obstruction occurs 5-10 minutes later, open the heat insulation baffle and release the electric heating rod to heat the oil and wax in the heating chamber. The heating speed can be controlled according to the power supply current. After about 10-15 minutes, retract the heating rod and raise the device. (Note: If the viscosity is too high, auxiliary agents can also be injected into the well at the same time as the device is lowered to assist in unblocking.)

[0041] (3) Lower the device again and repeat step (2) until the blockage is successfully cleared.

[0042] (4) After lowering the device for another 5-10 meters, stop working, retrieve the crawling arm and the retractable rotating scraper, turn off the power to stop heating, and lift the retrieval device.

[0043] The embodiments described above are merely preferred embodiments of the present invention, and not all feasible embodiments of the present invention. Any obvious modifications made by those skilled in the art without departing from the principles and spirit of the present invention should be considered to be included within the scope of protection of the claims of the present invention.

Claims

1. A process for unblocking oil pipes using an electrically heated dewaxing and unblocking device, characterized in that, The oil pipe electric heating dewaxing and unblocking device includes a cable (1), a crawling arm (3), a motor (4), a hollow rod (5), a retractable scraper (6), a solvent storage box (7), a rotating ring (8), a hollow heating body (9), a heating baffle (10), a heating rod (11), a retractable support rod (12), a resistance wire, a steel pipe (92), a heat insulation layer (93), and a heating head; wherein the cable (1) is connected to the hollow rod (5), and the hollow rod (5) is provided with the crawling arm (3), the motor (4), the solvent storage box (7), the rotating ring (8), and the retractable support rod (12) in sequence from top to bottom. The rotating ring (8) is provided with a retractable scraper (6), and the retractable scraper (6) is provided on the rotating ring (8). The bottom is provided with a cavity heating body (9), and the bottom of the telescopic support rod (12) is equipped with a heating baffle (10). The outer periphery of the heating baffle (10) is connected to the cavity heating body (9), and the bottom of the heating baffle (10) is provided with a heating rod (11). The cavity heating body (9) is composed of a resistance wire a (91), a steel pipe (92), a heat insulation layer (93), a cavity heating body body (94), and a heating head a (95). The heating baffle (10) is composed of a resistance wire c (101) and the upper edge of the heating baffle (102). The heating rod (11) is composed of a resistance wire b (111), a heating rod body (112), and a heating head b (113). The unblocking process includes the following steps: S1. Connect the device on the ground; S2. Lower the oil pipe electric heating test device into the oil pipe; S3. Lower the instrument to the blockage location, lift it up 5-10 meters, open the crawling arm (3) and the retractable scraper (6), and the crawling arm (3) and the retractable scraper (6) are spread out and tightly fitted to the inner wall of the pipe; S4. The motor is turned on, the retractable scraper (6) and the cavity heating body (9) are heated and rotated, the retractable scraper (6) scrapes the residual blockage on the inner wall of the pipe, the cavity heating body (9) rotates to unblock, the crawling arm (3) pushes the cavity heating body (9) downward. If the thickness of the obstruction position is less than the height of the heating cavity, the instrument is slowly lowered and unblocked by bottom rotation and heating; if the thickness of the obstruction position is greater than the height of the heating cavity and the viscosity of the blockage is small, the heating rod (11) is released to heat the oil and wax in the heating cavity; if the viscosity of the blockage is large, the heating rod (11) is released to heat the oil and wax in the heating cavity and the solvent or viscosity reducer in the device is released; if the viscosity of the blockage is too large, auxiliary agents are injected into the well at the same time as the device is lowered to assist in unblocking; the heating speed is controlled according to the power supply current, and the waiting time is set according to the situation. After the waiting time ends, the heating rod is retracted and the instrument is lifted. S5. Lower the instrument again and repeat step S4 until the blockage is successfully cleared; S6. Continue to lower the instrument 5-10 meters, stop working, retrieve the crawling arm (3) and the retractable scraper (6), turn off the power to stop heating, and lift the instrument back up.

2. The unblocking process of the oil pipe electric heating dewaxing and unblocking device according to claim 1, characterized in that, The upper edge (102) of the heating baffle is made of insulating material, and a resistance wire c (101) is wound around the center.

3. The unblocking process of the oil pipe electric heating dewaxing and unblocking device according to claim 1, characterized in that, The cavity heating body (94) is made of insulating material. A resistance wire a (91) is wrapped around the cavity heating body (94). A steel pipe (92) is provided on the outer wall. A heat insulation layer (93) is provided between the steel pipe (92) and the cavity heating body (94). A heating head a (95) is installed at the bottom of the cavity heating body (9).

4. The unblocking process of the oil pipe electric heating dewaxing and unblocking device according to claim 1, characterized in that, The heating rod body (112) is made of insulating material, and a resistance wire b (111) is wrapped around the heating rod body (112). A heating head b (113) is provided at the bottom of the heating rod (11).

5. The unblocking process of the oil pipe electric heating dewaxing and unblocking device according to any one of claims 2-4, characterized in that, The insulating materials used for the upper edge of the heating baffle (102), the cavity heating body (94), and the heating rod body (112) are talc or silica.

6. The unblocking process of the oil pipe electric heating dewaxing and unblocking device according to any one of claims 2-4, characterized in that, The resistance wires in the center of the heating baffle (10), on the cavity heating body (94), and on the heating rod body (112) are made of nickel-chromium electrothermal alloy or iron-chromium-aluminum alloy.

7. The unblocking process of the oil pipe electric heating dewaxing and unblocking device according to claim 3, characterized in that, The insulation layer (93) between the steel pipe (92) and the cavity heating body (94) is made of polyurethane.

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