A system for inserting a steel pipe cable into an oil pipe from the outside.

Abstract

This invention provides a system for inserting a steel pipe cable into an oil pipe from outside the pipe, belonging to the field of offshore heavy oil thermal recovery technology. It includes a lower flange below the production tree, which is connected to a first oil pipe via a pipe hanger. The upper part of a passable packer is connected to the first oil pipe, and the lower part is connected to an electric pump Y-joint. The lower end of the electric pump Y-joint has two connectors: one connector is connected to the electric pump unit via a pipe section, and the other connector is connected to the cable-passing Y-joint via a second oil pipe. The end of the cable-passing Y-joint away from the second oil pipe is sequentially connected to a perforated pipe and a plug. This invention, by using a cable-passing Y-joint, allows the steel pipe cable to be inserted vertically using a bundled method and horizontally using an in-pipe method. This achieves annular electric heating above the cable-passing Y-joint and oil layer electric heating below the cable-passing Y-joint, while simultaneously solving the problem of difficult horizontal insertion of electric heating cables in heavy oil thermal recovery wells, thus improving operational safety.

Description

Technical Field

[0001] This utility model relates to the field of offshore heavy oil thermal recovery technology, and in particular to a system for a steel pipe cable to enter the oil pipe from the outside of the oil pipe. Background Technology

[0002] Due to its high viscosity and high friction, heavy oil experiences significant flow resistance within reservoirs and wellbores, hindering efficient extraction. However, its viscosity is extremely sensitive to temperature; rising temperatures cause a sharp decrease in viscosity. Electric heating technology for heavy oil is suitable for oilfields with poor steam injection performance and is currently a key technology being developed for heavy oil thermal recovery. Regarding the installation method of the electric heating cable, since offshore heavy oil thermal recovery wells are typically horizontal wells with long horizontal sections, and due to limitations imposed by existing wellhead and downhole control tools requiring an empty tubing section during operation, the electric heating cable can currently only be installed by external binding. However, when the tubing reaches the horizontal section, the electric heating is prone to failure due to significant friction from the tubing wall.

[0003] Therefore, there is a need for an electric heating cable installation system to meet the process and safety requirements of offshore heavy oil thermal recovery wells and to achieve safe and efficient installation of the electric heating cable. Utility Model Content

[0004] In view of this, the present invention aims to propose a system for inserting a steel pipe cable into an oil pipe from outside the pipe. Combining the characteristics of the existing tubing structure in offshore oilfields, and without changing the existing processes and tool working conditions, the system uses a cable passing through a Y-joint to achieve annular electric heating above the cable passing through the Y-joint and oil layer electric heating below the cable passing through the Y-joint. This solves the problems of difficulty in inserting electric heating cables into heavy oil thermal recovery wells and the inability to achieve oil layer electric heating.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows: A system for a steel pipe cable to enter an oil pipe from outside the oil pipe includes a tree flange, a tubing hanger, a first oil pipe, a passable packer, an electric pump Y-joint, a tubing short section, an electric pump unit, a second oil pipe, a cable pass-through Y-joint, a perforated oil pipe, and a plug; the tree flange is connected to the first oil pipe via the tubing hanger; the upper part of the passable packer is connected to the first oil pipe, and the lower part is connected to the electric pump Y-joint; the lower end of the electric pump Y-joint is provided with two joints, one of which is connected to the electric pump unit via the tubing short section, and the other joint is connected to the cable pass-through Y-joint via the second oil pipe; the end of the cable pass-through Y-joint away from the second oil pipe is sequentially connected to a perforated oil pipe and a plug.

[0006] Furthermore, the oil pipe stub is located below the electric pump Y-joint.

[0007] Furthermore, the pre-production tree flange includes a pre-production tree flange body, a connecting pipeline hole, a discontinuous pipeline interface, a chemical reagent pipeline interface, a monitoring fiber optic cable hole, and a heating cable hole. The pre-production tree flange body is provided with the connecting pipeline hole, the discontinuous pipeline interface, the chemical reagent pipeline interface, the monitoring fiber optic cable hole, and the heating cable hole. The connecting pipeline hole and the heating cable hole are respectively provided through the upper and lower end faces of the pre-production tree flange body. The monitoring fiber optic cable hole is located in the pre-production tree flange body, with its upper end penetrating through the upper end face of the pre-production tree flange and its lower end communicating with the connecting pipeline hole. The discontinuous pipeline interface and the chemical reagent pipeline interface are respectively provided in the pre-production tree flange body.

[0008] Furthermore, the oil pipe hanger includes an oil pipe hanger body, a steel pipe cable crossing channel, and a monitoring optical cable crossing channel; the oil pipe hanger body is provided with an axial through hole, and at both ends of the axial through hole are respectively provided with sealing components for sealing the oil pipe hanger body and the monitoring optical cable, and sealing the oil pipe hanger body and the steel pipe cable; on both sides of the oil pipe hanger body are provided monitoring optical cable crossing channels for passing through the monitoring optical cable, and steel pipe cable crossing channels for passing through the steel pipe cable.

[0009] Furthermore, the electric pump Y-connector includes an electric pump Y-type through-connector, an upper connector, a lower connector, and an electric pump connector; the upper end of the upper connector is provided with an internal thread for connecting to the oil pipe, and the lower end is provided with an internal thread for connecting to the lower connector; the lower inner wall of the electric pump Y-type through-connector is provided with an electric pump connector for connecting to the electric pump unit; the electric pump connector has a through-hole structure, and its through-hole structure sequentially connects the inner cavity of the electric pump Y-type through-connector and the inner cavity of the upper connector.

[0010] Furthermore, the cable crossing Y-joint includes a tubing adapter, a suspension locking ring assembly, a crossing sealing assembly, a cable Y-type crossing joint, and a lower end joint; the external thread of the tubing adapter is connected to the internal thread at the lower end of the cable Y-type crossing joint, and the internal thread at the upper end of the cable Y-type crossing joint is connected to the lower end joint; the lower sidewall of the cable Y-type crossing joint is provided with an axial through hole and a sealing chamber for passing through the steel pipe cable and the crossing sealing assembly, wherein the axial through hole and the sealing chamber penetrate through the cable Y-type crossing joint and the lower end joint.

[0011] Compared to existing technologies, the steel pipe cable system described in this utility model, which allows the cable to enter the oil pipe from the outside, has the following advantages: This system enables in-pipe heating of the reservoir section via electric heating. Considering the characteristics of existing tubing structures in offshore oilfields, and without altering the existing process, wellbore, or main tubing dimensions, the system utilizes a cable-passing Y-joint to achieve annular electric heating above the Y-joint and oil layer electric heating below the Y-joint. This also solves the problem of difficult horizontal installation of electric heating cables in heavy oil thermal recovery wells, improving operational safety. Attached Figure Description

[0012] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:

[0013] Figure 1 This is a schematic diagram of a system for a steel pipe cable to enter an oil pipe from outside the pipe, as described in an embodiment of this utility model.

[0014] Figure 2 This is a schematic diagram of the structure of the lower flange of the wellhead described in this utility model;

[0015] Figure 3 This is a schematic diagram of the oil pipe hanger described in this utility model;

[0016] Figure 4 This is a schematic diagram of the structure of the electric pump Y-connector described in this utility model;

[0017] Figure 5 This is a schematic diagram of the cable crossing Y-joint of this utility model.

[0018] Explanation of reference numerals in the attached figures:

[0019] 1-1. No. 1 flange under the wellhead; 1-2. Tubing hanger; 1-3. First tubing; 1-4. Electric pump cable; 1-5. Passable packer; 1-6. Electric pump Y-joint; 1-7. Tubing short section; 1-8. Electric pump unit; 1-9. Second tubing; 1-10. Cable passing Y-joint; 1-11. Perforated tubing; 1-12. Circular plug; 1-1-1. Connecting pipeline hole; 1-1-2. Discontinuous pipeline interface; 1-1-3. Chemical reagent pipeline interface; 1-1-4. Monitoring fiber optic cable hole; 1-1-5. Heating cable hole; 1-2-1, Oil pipe hanger body; 1-2-2, Steel pipe cable crossing channel; 1-2-3, Monitoring optical cable crossing channel; 1-6-1, Electric pump Y-type crossing joint; 1-6-2, Upper end connector; 1-6-3, Lower end connector; 1-6-4, Electric pump connector; 1-10-1, Oil pipe buckle; 1-10-2, Suspension locking ring assembly; 1-10-3, Crossing sealing assembly; 1-10-4, Cable Y-type crossing joint; 1-10-5, Lower end connector; 1-13, Steel pipe cable. Detailed Implementation

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0021] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] like Figures 1-5 As shown, this utility model is a system for steel pipe cables to enter the oil pipe from the outside of the oil pipe. It can be used for in-pipe heating of the reservoir section of heavy oil thermal recovery wells in offshore oil fields. It includes a tree flange 1-1, a tubing hanger 1-2, a first oil pipe 1-3, an electric pump cable 1-4, a passable packer 1-5, an electric pump Y-connector 1-6, a tubing short section 1-7, an electric pump unit 1-8, a second oil pipe 1-9, a cable passing Y-connector 1-10, a perforated oil pipe 1-11, and a round plug 1-12. The tree flange 1-1, tubing hanger 1-2, and first oil pipe 1-3 are connected sequentially from top to bottom. The upper part of the passable packer 1-5 is connected to the first oil pipe 1-3, and the lower end is connected to the electric pump Y-connector 1-6 through the oil pipe. The oil pipe is existing technology. The lower end of the electric pump Y-connector 1-6 is provided with two connectors. One connector is connected to the electric pump unit 1-8 through an oil pipe short section 1-7, and the oil pipe short section 1-7 is located at the lower part of the electric pump Y-connector 1-6. The electric pump unit 1-8 is electrically connected to the electric pump cable 1-4. The other connector of the electric pump Y-connector 1-6 is connected to the cable passing Y-connector 1-10 through a second oil pipe 1-9. The end of the cable passing Y-connector 1-10 away from the second oil pipe 1-9 is connected in sequence to a perforated oil pipe 1-11 and a round plug 1-12. In the description of this utility model, it should be understood that the terms "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0023] In this system, the production tree flange 1-1, tubing hanger 1-2, electric pump Y-connector 1-6, and cable crossing Y-connector 1-11 are key tools for the wellbore string.

[0024] The pre-production tree flange 1-1 is provided with a connecting pipeline hole 1-1-1, a discontinuous pipeline interface 1-1-2, a chemical agent pipeline interface 1-1-3, a monitoring optical cable hole 1-1-4, and a heating cable hole 1-1-5. The connecting pipeline hole 1-1-1 and the heating cable hole 1-1-5 are respectively installed through the upper and lower end faces of the pre-production tree flange 1-1. The monitoring optical cable hole 1-1-4 is located within the body of the pre-production tree flange 1-1, with its upper end penetrating through the upper end face of the pre-production tree flange 1-1 and its lower end communicating with the connecting pipeline hole 1-1-1. The discontinuous pipeline interface 1-1-2 and the chemical agent pipeline interface 1-1-3 are respectively located within the body of the pre-production tree flange 1-1. Connecting pipe hole 1-1-1 is the exit channel for the hydraulic control pipeline; discontinuous pipeline interface 1-1-2 is used for temporary pipeline connections; chemical agent pipeline interface 1-1-3 is used for chemical agent injection; monitoring optical cable hole 1-1-4 is the exit channel for the monitoring optical cable; and heating cable hole 1-1-5 is the exit channel for the steel conduit cable 1-13. The hydraulic control pipeline, chemical agent, monitoring optical cable, and steel conduit cable 1-13 are all existing technologies.

[0025] The tubing hanger 1-2 is a device used to suspend tubing strings and provide a seal between the suspended tubing and the pre-works tree flange 1-1. The tubing hanger 1-2 includes a tubing hanger body 1-2-1, a steel pipe cable passageway 1-2-2, and a monitoring optical cable passageway 1-2-3. The tubing hanger body 1-2-1 has an axial through hole, and both ends of the axial through hole are respectively provided with sealing components (not shown in the figure, the sealing components are prior art) for sealing the tubing hanger body 1-2-1 and the monitoring optical cable, and for sealing the tubing hanger body 1-2-1 and the steel pipe cable 1-13. The upper end of the tubing hanger body 1-2-1 has an internal thread for lowering the tubing string, and the lower end has an internal thread for connecting to the upper section of the tubing string. The tubing string is prior art. Monitoring optical cable passageways 1-2-3 for passing through the monitoring optical cable and steel pipe cable passageways 1-2-2 for passing through the steel pipe cable 1-13 are provided on both sides of the tubing hanger body 1-2-1.

[0026] The electric pump Y-connector 1-6 is used to connect the upper and lower oil pipes and the electric pump unit 1-8. The electric pump Y-connector 1-6 includes an electric pump Y-type through connector 1-6-1, an upper connector 1-6-2, a lower connector 1-6-3, and an electric pump connector 1-6-4. The upper connector 1-6-2 has an internal thread at the upper end for connecting to the oil pipe, and an internal thread at the lower end for connecting to the lower connector 1-6-3. The lower inner wall of the electric pump Y-type through connector 1-6-1 has an electric pump connector 1-6-4 for connecting to the electric pump unit 1-8. The electric pump connector 1-6-4 has a through hole structure, which sequentially connects the inner cavity of the electric pump Y-type through connector 1-6-1 and the inner cavity of the upper connector.

[0027] The cable crossing Y-joint 1-10 is used to transfer the steel pipe cable 1-13 from the outside to the inside of the oil pipe. The cable crossing Y-joint 1-10 includes an oil pipe adapter 1-10-1, a suspension locking ring assembly 1-10-2, a crossing sealing assembly 1-10-3, a cable Y-type crossing connector 1-10-4, and a lower end connector 1-10-5. The external thread of the oil pipe adapter 1-10-1 connects to the internal thread at the lower end of the cable Y-type crossing connector 1-10-4, and the internal thread at the upper end of the cable Y-type crossing connector 1-10-4 connects to the lower end connector 1-10-5. The lower sidewall of the cable Y-type crossing connector 1-10-4 has an axial through hole and a sealing chamber for the steel pipe cable and the crossing sealing assembly 1-10-3. The axial through hole and the sealing chamber penetrate the cable Y-type crossing connector 1-10-4 and the lower end connector 1-10-5, thereby transferring the steel pipe cable 1-13 from the outside to the inside of the pipe.

[0028] In actual operation, the cable is connected sequentially from top to bottom through Y-connector 1-10, perforated tubing 1-11, and round plug 1-12. The connected cable through Y-connector 1-10, perforated tubing 1-11, and round plug 1-12 are then lowered into the well as a whole from the wellhead. It should be noted that when lowering the whole assembly, round plug 1-12 is lowered into the well first. When the cable passing through the Y-joint 1-10 reaches the wellhead position, the lower end of the steel pipe cable 1-13 passes through the cable passing through the Y-joint 1-10, and then is slowly lowered into the perforated tubing 1-11 by gravity and connected to the bottom plug 1-12. The second tubing 1-9 is then lowered and connected to the upper end of the cable passing through the Y-joint 1-10. At the same time, the steel pipe cable 1-13 is fixed to the second tubing 1-9 by the cable cover (which is existing technology). Then, the electric pump unit 1-8, tubing short section 1-7, electric pump Y-joint 1-6, passable packer 1-5, electric pump cable 1-4, first tubing 1-3, tubing hanger 1-2, and production tree flange 1-1 are lowered in sequence. The system described in this utility model achieves annular electric heating above the cable crossing Y-joint and oil layer electric heating below the cable crossing Y-joint, thereby realizing heating of the entire well section. It also solves the problems of difficulty in running steel pipe cables in heavy oil thermal recovery wells and the inability to achieve oil layer electric heating, thus improving operational safety.

[0029] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A system for running a steel pipe cable from outside a tubing string into the tubing string, characterized by: This includes the pre-nut flange (1-1), tubing hanger (1-2), first tubing (1-3), passable packer (1-5), electric pump Y-joint (1-6), tubing short section (1-7), electric pump unit (1-8), second tubing (1-9), cable passable Y-joint (1-10), perforated tubing (1-11), and round plug (1-12); the pre-nut flange (1-1) is connected to the first tubing (1-3) via the tubing hanger (1-2), and the passable packer (1-5). The upper part is connected to the first oil pipe (1-3), and the lower part is connected to the electric pump Y connector (1-6). The lower end of the electric pump Y connector (1-6) is provided with two connectors. One connector is connected to the electric pump unit (1-8) through the oil pipe short section (1-7), and the other connector is connected to the cable passing Y connector (1-10) through the second oil pipe (1-9). The end of the cable passing Y connector (1-10) away from the second oil pipe (1-9) is connected in sequence to the perforated oil pipe (1-11) and the round plug (1-12).

2. A system for electrically cabling a steel pipe from outside the pipe to inside the pipe according to claim 1, characterized in that: The oil pipe stub (1-7) is located below the electric pump Y-joint (1-6).

3. A system for electrically cabling a steel pipe from outside the pipe to inside the pipe according to claim 1, characterized in that: The pre-production tree flange (1-1) includes the flange body, a connecting pipeline hole (1-1-1), a discontinuous pipeline interface (1-1-2), a chemical agent pipeline interface (1-1-3), a monitoring optical cable hole (1-1-4), and a heating cable hole (1-1-5). The flange body has the connecting pipeline hole (1-1-1), the discontinuous pipeline interface (1-1-2), the chemical agent pipeline interface (1-1-3), the monitoring optical cable hole (1-1-4), and the heating cable hole (1-1-5). Meanwhile, the connecting pipeline hole (1-1-1) and the heating cable hole (1-1-5) are respectively installed through the upper and lower end faces of the bottom flange (1-1) body of the tree. The monitoring optical cable hole (1-1-4) is installed in the body of the bottom flange (1-1), and the upper end of the monitoring optical cable hole (1-1-4) is installed through the upper end face of the bottom flange (1-1), while the lower end is connected to the connecting pipeline hole (1-1-1). The discontinuous pipeline interface (1-1-2) and the chemical agent pipeline interface (1-1-3) are respectively installed in the body of the bottom flange (1-1).

4. A system for electrically pumping a fluid from outside a pipe to inside a pipe according to claim 1, wherein: The oil pipe hanger (1-2) includes an oil pipe hanger body (1-2-1), a steel pipe cable crossing channel (1-2-2), and a monitoring optical cable crossing channel (1-2-3). The oil pipe hanger body (1-2-1) is provided with an axial through hole, and at both ends of the axial through hole are respectively provided with sealing components for sealing the oil pipe hanger body (1-2-1) and the monitoring optical cable, and sealing the oil pipe hanger body (1-2-1) and the steel pipe cable (1-13). On both sides of the oil pipe hanger body (1-2-1) are provided a monitoring optical cable crossing channel (1-2-3) for passing through the monitoring optical cable, and a steel pipe cable crossing channel (1-2-2) for passing through the steel pipe cable (1-13).

5. A system for electrically pumping a fluid from outside a pipe to inside a pipe as defined in claim 1, wherein: The electric pump Y-connector (1-6) includes an electric pump Y-type through connector (1-6-1), an upper connector (1-6-2), a lower connector (1-6-3), and an electric pump connector (1-6-4). The upper connector (1-6-2) has an internal thread at its upper end that connects to the oil pipe, and an internal thread at its lower end that connects to the lower connector (1-6-3). The lower inner wall of the electric pump Y-type through connector (1-6-1) is provided with an electric pump connector (1-6-4) that connects to the electric pump unit (1-8). The electric pump connector (1-6-4) has a through hole structure, and its through hole structure sequentially connects the inner cavity of the electric pump Y-type through connector (1-6-1) and the inner cavity of the upper connector.

6. A system for electrically pumping a fluid from outside a pipe to inside a pipe according to claim 1, wherein: The cable crossing Y-joint (1-10) includes a pipe buckle (1-10-1), a suspension locking ring assembly (1-10-2), a crossing sealing assembly (1-10-3), a cable Y-type crossing joint (1-10-4), and a lower end joint (1-10-5). The external thread of the pipe buckle (1-10-1) is connected to the internal thread at the lower end of the cable Y-type crossing joint (1-10-4), and the internal thread at the upper end of the cable Y-type crossing joint (1-10-4) is connected to the lower end joint (1-10-5). The lower side wall of the cable Y-type crossing joint (1-10-4) is provided with an axial through hole and a sealing chamber for passing through steel pipe cables and the crossing sealing assembly (1-10-3), wherein the axial through hole and the sealing chamber penetrate through the cable Y-type crossing joint (1-10-4) and the lower end joint (1-10-5).

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