Single pipe self-insulation water mixing process wellhead combination device

Abstract

The application discloses a single-pipe self-heat-preservation water-mixing process wellhead combined device, and belongs to the field of oil exploitation wellhead equipment. The device takes an integrated valve body base body forged as a whole as a main body, a water-mixing inner cavity, a produced liquid flow channel and a sleeve pipe communication flow channel are arranged in the valve body, the water-mixing inner cavity directly intersects with the produced liquid flow channel in the valve body, and an external water-mixing connecting pipeline is omitted; an adjustable flow regulating nozzle assembly is arranged in the produced liquid flow channel, and a heat-preservation sandwich cavity with an avoiding hole is coated outside the valve body. The single-pipe self-heat-preservation water-mixing process wellhead combined device is used to integrate the water-mixing and oil production gathering and transportation functions, reduce field joint leakage points, realize valve body anti-freezing by relying on the heat-preservation sandwich, be suitable for oilfield electric pump well single-pipe water-mixing gathering and transportation working conditions, and be convenient to install and maintain, and is high in practicality.

Description

Technical Field

[0001] This invention relates to the field of oil wellhead equipment technology, and in particular to a single-pipe self-insulating water-injection process wellhead assembly device. Background Technology

[0002] In oilfield electric pump well production, the single-pipe water-injection gathering and transportation process is widely used. This relies on injecting hot water into the gathering and transportation pipeline to reduce crude oil viscosity and ensure smooth flow of oil and gas. Existing electric pump wellhead equipment is mostly assembled from separate valves, pressure gauge seats, throttle nozzles, and venting valves. Each component is installed independently, resulting in numerous pipeline joints, a high risk of leakage, significant space occupation at the wellhead, and cumbersome installation and maintenance procedures. Furthermore, conventional wellheads lack integrated self-insulating structures, making them highly susceptible to crude oil condensation and freezing in low-temperature winter conditions, affecting continuous well production. Additionally, traditional wellhead casing pressure venting, oil pressure sampling, and flow regulation require multiple independent valves, involving numerous operational steps, high manual labor intensity, and dispersed pressure measurement points leading to large errors in pressure readings. This lack of modular integration of water injection, oil production, casing pressure gathering, and pressure monitoring functions fails to achieve comprehensive functionality.

[0003] While existing related devices can complete basic pressure tapping, throttling, and pressure collection, they lack integrated water mixing channels, lack self-insulating protection structures, require separate external pipelines and valves for the water mixing process, have many on-site welded joints, and suffer from significant freezing and blockage problems in winter, resulting in insufficient equipment integration.

[0004] Therefore, it is necessary to develop a single-pipe self-insulating water mixing process wellhead combination device to solve the technical problems of existing technology, such as numerous joints, easy freezing and blockage, dispersed functions, and complex installation and maintenance. Summary of the Invention

[0005] The purpose of this invention is to provide a single-pipe self-insulating water injection process wellhead combination device, which solves the technical problems of numerous joints, easy freezing and blockage, dispersed functions, and complex installation and maintenance in the existing technology, and realizes the integrated function of electric pump well water injection, oil production, casing gas collection, pressure monitoring, sampling, constant pressure gas release, and flow regulation.

[0006] To achieve the above objectives, the present invention provides a single-tube self-insulating water-injection process wellhead assembly device, comprising an integrally forged valve body base, wherein multiple mutually cooperating internal flow channels are machined inside the integral valve body base; an oil inlet pipe DN65 interface is vertically arranged on the lower side of the integral valve body base, the oil inlet pipe DN65 interface is internally connected to the water-injection cavity inside the valve body, and the water-injection cavity is connected to the produced fluid flow channel inside the integral valve body base; The output fluid channel runs horizontally through the integrated valve body base. The output end of the output fluid channel is connected to the output interface, and the output interface is connected to the oil pipe clamp interface. An adjustable oil nozzle assembly is installed inside the channel section of the output fluid channel near the oil pipe clamp interface. The integrated valve body base has a DN32 connecting sleeve interface on its downward-sloping side wall, and the DN32 connecting sleeve interface is connected to the inward connecting sleeve and the flow channel. The integrated valve body base is externally covered with a self-insulating protective component. The self-insulating protective component is provided with an insulation interlayer cavity, which completely encloses the integrated valve body base. The insulation interlayer cavity has a clearance hole, through which the connecting oil pipe clamp interface, the oil inlet pipe DN65 interface, the connecting sleeve DN32 interface, and the valve stems of each valve component protrude outward.

[0007] Preferably, the sleeve connecting channel and the product liquid channel are isolated from each other, and the sleeve connecting channel is respectively connected to the constant pressure venting valve and the sleeve pressure valve. The constant pressure venting valve is fixedly installed on the upper part of the integrated valve body base.

[0008] Preferably, a pressure tapping valve is connected to the pressure tapping branch of the sleeve connecting flow channel, and a pressure tapping gauge seat is assembled on the outside of the pressure tapping valve; A return oil pressure valve is connected to the pressure tapping branch of the produced liquid flow channel, and a return oil pressure gauge seat is installed on the outside of the return oil pressure valve; an oil sampling valve is connected to the sampling branch of the produced liquid flow channel.

[0009] Preferably, a single-flow shut-off valve is installed upstream of the produced fluid flow channel to prevent backflow of media from the external gathering and transportation network; a main shut-off valve is installed on the outer right side of the integrated valve body base to control the opening and closing of the wellhead main passage.

[0010] Preferably, the oil pressure recovery valve controls the opening and closing of the pressure tapping branch of the produced fluid flow channel, and the sleeve pressure recovery valve controls the opening and closing of the pressure tapping branch of the sleeve connecting flow channel.

[0011] Preferably, the oil sampling valve is connected to the sampling branch of the produced fluid flow channel and is used for oil sampling operations at the wellhead.

[0012] Preferably, the casing connecting channel is completely isolated from the water mixing inner cavity and the product liquid channel, and the casing connecting channel is connected to the oil sleeve annulus only through the DN32 interface of the connecting casing; the constant pressure venting valve is directly connected to the casing connecting channel and is used to automatically release pressure and vent when the casing annulus is overpressured.

[0013] Furthermore, the water mixing chamber and the output liquid flow channel achieve media convergence and mixing only within the integrated valve body base, without the need for external pipeline welding connections.

[0014] Preferably, the insulation interlayer cavity has an insulation medium filling port, a sealing plug is matched to the insulation medium filling port, and the outside of the insulation interlayer cavity is covered with an anti-corrosion protective shell.

[0015] Preferably, a filling gap is reserved between the thermal insulation interlayer cavity and the integrated valve body base, and the filling gap is filled with thermal insulation cotton or injected with thermally conductive antifreeze.

[0016] Preferably, the adjustable flow nozzle assembly is a quick-install structure, which allows for nozzle opening adjustment or nozzle replacement without disassembling the integrated valve body base, thereby adjusting the output flow rate of the produced liquid.

[0017] Therefore, the present invention employs the above-mentioned single-pipe self-insulating water mixing process wellhead combination device, and the technical effects are as follows: 1) This device uses an integrated valve body base as a carrier and directly opens the water mixing cavity inside the valve body. The water mixing medium is mixed with the produced fluid inside the valve body, eliminating the structure of external water mixing pipelines. At the same time, a fully enclosed self-insulating protective component is set on the outside of the valve body base and the left side of the tubing clamp interface to completely wrap and insulate the valve body. This is different from the existing wellhead equipment with separate valves and has novelty.

[0018] 2) This invention integrates water mixing, oil production, casing gas collection, pressure detection, sampling, and constant pressure venting into the same forged valve body. The medium distribution is achieved by relying on the flow channel layout of the valve body itself, greatly reducing the number of flanges and welded joints on site. The insulation jacket cavity uses clearance holes to allow each pipeline joint and valve stem to extend outward, only insulating the valve body itself, taking into account both assembly interference and antifreeze effect. It does not require multiple independent equipment combinations and is innovative.

[0019] 3) On-site installation only requires connecting the oil pipe, casing, and water injection pipeline, reducing the amount of on-site construction; it can directly complete oil pressure and casing pressure reading, oil sampling, automatic casing venting, and production flow regulation; the self-insulating structure is suitable for the low temperature conditions in northern oilfields in winter, reducing freezing and shutdown failures, and is easy to maintain, making it suitable for large-scale promotion in electric pump wells.

[0020] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of an embodiment of a single-pipe self-insulating water mixing process wellhead combination device of the present invention.

[0022] Figure Labels 1. Insulated jacket cavity; 2. One-way shut-off valve; 3. Constant pressure vent valve; 4. Oil pressure return valve; 5. Sleeve pressure return valve; 6. Oil inlet pipe DN65 interface; 7. Connecting sleeve DN32 interface; 8. Main shut-off valve; 9. Insulation medium filling port; 10. Oil pressure sample valve; 11. Output interface. Detailed Implementation

[0023] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0025] Example 1 A single-pipe self-insulating water mixing process wellhead assembly device, such as Figure 1 As shown, the main body of the device is an integrally forged valve body base. Multiple interlocking internal flow channels are machined within the integrated valve body base, including a water-mixing chamber, a produced fluid flow channel, and a casing connection flow channel. A DN65 inlet pipe interface 6 is vertically installed on the lower side of the integrated valve body base. During field operations, this DN65 inlet pipe interface 6 connects to the oilfield's hot water mixing pipeline. Hot water enters the water-mixing chamber inside the valve body via the DN65 inlet pipe interface 6. The water-mixing chamber directly intersects and connects with the produced fluid flow channel inside the valve body base. The hot water mixes directly with the crude oil produced in the well inside the valve body, reducing the crude oil viscosity. This eliminates the need for welding a water-mixing manifold to the outside of the valve body, reducing leakage joints.

[0026] The produced fluid flow channel horizontally penetrates the integrated valve body base. An output interface 11 is provided at the output end of the produced fluid flow channel, and this interface 11 is fitted with a tubing clamp interface, which connects to the surface gathering and transportation pipeline. An adjustable flow nozzle assembly is installed inside the flow channel section near the tubing clamp interface. In this embodiment, the adjustable flow nozzle assembly adopts a quick-installation structure, eliminating the need to disassemble the valve body base. Nozzle replacement or opening adjustment can be performed directly from the outside, thereby changing the output flow rate of the produced fluid to adapt to different well production conditions.

[0027] The integrated valve body base has a DN32 connection port 7 on its downward-sloping side wall. The DN32 connection port 7 connects to the wellhead casing valve and connects inward to the casing connecting channel. The casing connecting channel is isolated from the produced fluid channel. The casing connecting channel connects upward to the constant pressure venting valve 3 and the casing pressure tapping valve 5 respectively. The constant pressure venting valve 3 is fixed on the upper part of the integrated valve body base. The casing connecting channel connects to the annulus only through the DN32 connection port 7. When the gas pressure accumulated in the annulus exceeds the set threshold of the constant pressure venting valve 3, the constant pressure venting valve 3 automatically opens to release pressure and gas. After the pressure drops back to the set value, the valve automatically closes, realizing constant pressure gas collection in the casing.

[0028] The casing connecting channel branches off into corresponding pressure tapping branches. A casing pressure tapping valve 5 is connected to each pressure tapping branch of the casing connecting channel. A casing pressure tapping gauge holder is mounted on the outside of the casing pressure tapping valve 5, and a pressure gauge can be installed on the site. Opening the casing pressure tapping valve 5 allows reading the casing pressure value in the annulus. The produced fluid flow channel is equipped with separate pressure tapping and sampling branches. A return oil pressure valve 4 is connected to the pressure tapping branch of the produced fluid flow channel. A return oil pressure gauge holder is mounted on the outside of the return oil pressure valve 4, and a pressure gauge is installed on the return oil pressure gauge holder. Opening the return oil pressure valve 4 allows reading the wellhead oil pressure. An oil sampling valve 10 is connected to the sampling branch. After closing other valves, opening the oil sampling valve 10 allows for the collection of wellhead produced fluid oil samples for well property testing.

[0029] A single-flow shut-off valve 2 is installed upstream of the produced fluid flow channel to prevent high-pressure media from the surface gathering and transportation network from flowing back into the wellbore. A main shut-off valve 8 is installed on the outer right side of the integrated valve body base. The main shut-off valve 8 serves as the main switch at the wellhead, controlling the overall opening and closing of the main wellbore passage. During maintenance operations, the main shut-off valve 8 is closed to achieve wellhead isolation.

[0030] The integrated valve body base is externally covered with a self-insulating protective component, which includes an insulated interlayer cavity 1 that completely encloses the integrated valve body base. The insulated interlayer cavity 1 has clearance holes through which the connecting oil pipe clamp interface, the DN65 inlet oil pipe interface 6, the DN32 connecting sleeve interface 7, and the valve stems of each valve component extend outwards to avoid assembly interference. An insulation medium filling port 9 is provided on the insulation interlayer cavity 1, equipped with a sealing plug. An anti-corrosion protective shell is provided on the outside of the insulation interlayer cavity 1. A filling gap is left between the insulation interlayer cavity 1 and the integrated valve body base. In this embodiment, under low-temperature conditions in northern winters, thermally conductive antifreeze is added to the filling gap through the insulation medium filling port 9, and the sealing plug is tightened after filling. Alternatively, insulation cotton can be filled into the filling gap to simultaneously insulate the valve body base, internal flow channels, valve components, and adjustable flow nozzle assembly, preventing crude oil from freezing and condensing at low temperatures.

[0031] The on-site installation process of this device is as follows: The integrated valve body base is positioned and connected to the DN65 inlet pipe interface 6, the DN32 casing interface 7, and the output interface 11, respectively; pressure gauges are installed on each gauge base; the insulation jacket cavity 1 is filled with insulation medium; after completion, the main shut-off valve 8 is opened, allowing the well-produced fluid to enter the produced fluid flow channel, while the mixed hot water enters the water mixing cavity through the DN65 inlet pipe interface 6. After mixing inside the valve body, the mixture is throttled and pressure-regulated by the adjustable flow nozzle assembly before being delivered to the gathering and transportation pipeline; operators can read the oil pressure and casing pressure using pressure gauges and collect oil samples using the oil pressure sampling valve 10; when the annular pressure exceeds the limit, the constant pressure venting valve automatically releases pressure.

[0032] Example 2 This embodiment is basically the same as the first embodiment in structure, except that: the gap of the insulation jacket cavity 1 is filled with insulation cotton, and no thermally conductive antifreeze is added. It is suitable for the working environment in the autumn and spring of the oil field where the temperature is not lower than -10℃. The valve body is insulated by the insulation cotton, which simplifies the on-site maintenance and does not require the regular addition of antifreeze.

[0033] Example 3 This embodiment is basically the same as the first embodiment in structure, except that: the adjustable flow nozzle assembly uses different specifications of throttling valve cores. By changing the specifications of the valve cores, the production fluid flow rate can be adjusted, which is suitable for the production conditions of electric pump wells with large fluctuations in production volume.

[0034] Therefore, the present invention adopts the above-mentioned single-pipe self-insulating water injection process wellhead combination device, which has a simple structure and solves the technical problems of numerous joints, easy freezing and blockage, dispersed functions, and complex installation and maintenance in the existing technology. It realizes the integrated function of electric pump well water injection, oil production, casing gas collection, pressure monitoring, sampling, constant pressure gas release, and flow regulation.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A single-pipe self-insulating water mixing process wellhead assembly device, characterized in that: The system includes an integrally forged valve body base, which has multiple interoperable internal flow channels machined inside. A DN65 oil inlet pipe is vertically installed on the lower side of the integral valve body base, which connects inward to the water-mixing inner cavity inside the valve body. The water-mixing inner cavity intersects and communicates with the output liquid flow channel inside the integral valve body base. The output fluid channel runs horizontally through the integrated valve body base. The output end of the output fluid channel is connected to the output interface, and the output interface is connected to the oil pipe clamp interface. An adjustable oil nozzle assembly is installed inside the channel section of the output fluid channel near the oil pipe clamp interface. The integrated valve body base has a DN32 connecting sleeve interface on its downward-sloping side wall, and the DN32 connecting sleeve interface is connected to the inward connecting sleeve and the flow channel. The integrated valve body base is externally covered with a self-insulating protective component. The self-insulating protective component is provided with an insulation interlayer cavity, which completely encloses the integrated valve body base. The insulation interlayer cavity has a clearance hole, through which the connecting oil pipe clamp interface, the oil inlet pipe DN65 interface, the connecting sleeve DN32 interface, and the valve stems of each valve component protrude outward.

2. The single-pipe self-insulating water mixing process wellhead assembly device according to claim 1, characterized in that: The casing connecting channel and the output liquid channel are isolated from each other. The casing connecting channel is connected upward to the constant pressure venting valve and the casing pressure valve, respectively. The constant pressure venting valve is fixedly installed on the upper part of the integrated valve body base.

3. The single-pipe self-insulating water mixing process wellhead assembly device according to claim 2, characterized in that: A pressure tapping valve is connected to the pressure tapping branch of the casing connecting flow channel, and a pressure tapping gauge seat is assembled on the outside of the pressure tapping valve. A return oil pressure valve is connected to the pressure tapping branch of the produced liquid flow channel, and a return oil pressure gauge seat is installed on the outside of the return oil pressure valve; an oil sampling valve is connected to the sampling branch of the produced liquid flow channel.

4. The single-pipe self-insulating water mixing process wellhead assembly device according to claim 3, characterized in that: A single-flow shut-off valve is installed upstream of the produced fluid flow channel to prevent backflow of media from the external gathering and transportation network; a main shut-off valve is installed on the outer right side of the integrated valve body base to control the opening and closing of the wellhead main passage.

5. A single-pipe self-insulating water mixing process wellhead assembly device according to claim 4, characterized in that: The oil pressure recovery valve controls the opening and closing of the pressure tapping branch of the produced fluid flow channel, and the sleeve pressure valve controls the opening and closing of the pressure tapping branch of the sleeve connecting flow channel.

6. The single-pipe self-insulating water mixing process wellhead assembly device according to claim 5, characterized in that: The oil sampling valve is connected to the sampling branch of the produced fluid flow channel and is used for oil sampling operations at the wellhead.

7. A single-pipe self-insulating water mixing process wellhead assembly device according to claim 6, characterized in that, The casing connecting channel is completely isolated from the water mixing inner cavity and the product fluid channel. The casing connecting channel is connected to the oil sleeve annulus only through the DN32 interface of the connecting casing. The constant pressure venting valve is directly connected to the casing connecting channel and is used to automatically release pressure and vent when the casing annulus is overpressured.

8. The single-pipe self-insulating water mixing process wellhead assembly device according to claim 1, characterized in that: The insulation interlayer cavity has an insulation medium filling port, and a sealing plug is matched to the insulation medium filling port. The outside of the insulation interlayer cavity is covered with an anti-corrosion protective shell.

9. A single-pipe self-insulating water mixing process wellhead assembly device according to claim 8, characterized in that: A pre-filled gap is reserved between the thermal insulation interlayer cavity and the integrated valve body base, and the filling gap is filled with thermal insulation cotton or injected with thermally conductive antifreeze.

10. A single-pipe self-insulating water mixing process wellhead assembly device according to claim 1, characterized in that: The adjustable flow nozzle assembly has a quick-install structure, which allows for nozzle opening adjustment or nozzle replacement without disassembling the integrated valve body base, thereby adjusting the output flow rate of the produced liquid.

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