Wellhead deicing and dewaxing device

Abstract

The invention discloses a wellhead deicing and dewaxing device which comprises a flange connecting part, a heat insulation cavity, a conical flow guide body and a guide head which are connected in sequence. An internal steam channel penetrates through the flange connecting part, the heat insulation cavity, the conical flow guide body and the guide head, and a scraper assembly and a high-temperature and high-pressure steam nozzle are arranged around the conical flow guide body; and a heat insulation chamber is arranged between the flange connecting part and the conical flow guide body. The novel wellhead operation equipment is compact in structure, convenient to operate, efficient in heating, safe and reliable. The problems that a traditional wellhead deicing and dewaxing mode is tedious in operation, low in efficiency, poor in heat energy utilization rate, complex in structure and large in potential safety hazard are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of petroleum machinery, in particular to a wellhead deicing and dewaxing device. Background Art

[0002] During actual oilfield production in cold regions, where ambient temperatures remain below zero degrees Celsius for extended periods, ice and wax formation are very common at the wellhead and casing inlet. This is particularly pronounced during wellhead shutdowns, injection halts, or low-flow conditions. These conditions can lead to blockages in wellhead piping, freezing of wellhead valves, and seal failure of equipment, severely impacting well unsealing operations and continued production.

[0003] Traditional de-icing and dewaxing methods rely on manual scraping, chemical flushing, or high-temperature steam hose insertion and spraying. These methods generally suffer from low efficiency, uneven heat distribution, limited well depth, and high operator workload. These methods are particularly inefficient in cold and snowy weather and pose certain safety risks. Steam hoses struggle to achieve effective directional heating and precise control, while manual scraping is labor-intensive and prone to slipping and burns. While electric heating cables offer some automation capabilities, they are complex to install, costly to maintain, and slow to respond, making them unsuitable for emergency rapid removal.

[0004] Therefore, there is an urgent need to develop a new wellhead deicing and dewaxing device that is compact in structure, quickly deployed, and combines the functions of physical removal and thermal wax melting to improve the operating efficiency, safety, and continuity of low-temperature oilfields. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention aims to provide a wellhead de-icing and de-waxing device that features a compact structure, convenient operation, efficient heating, and safe and reliable performance. This device addresses the challenges of traditional wellhead de-icing and de-waxing methods, such as cumbersome operation, low efficiency, poor thermal energy utilization, complex structure, and significant safety risks.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A wellhead deicing and dewaxing device includes a flange connection portion 1, an insulating chamber 6, a conical guide body 2, and a guide head 7 connected in sequence; an internal steam passage 3 is provided through the flange connection portion 1, the insulating chamber 6, the conical guide body 2, and the guide head 7; a scraper assembly 4 and a high-temperature and high-pressure steam nozzle 5 are provided around the conical guide body 2;

[0008] A heat-insulating chamber 6 is provided between the flange connection portion 1 and the conical body guide 2 .

[0009] The flange connection part 1 and the conical guide body 2 are connected by bolts, and a pressure-resistant sealing gasket is provided on the joint surface to prevent steam leakage; the flange connection part 1 and the conical guide body 2 can also be manufactured by integral welding.

[0010] The steam channel 3 is welded integrally with the heat-insulating chamber 6 and the inner wall of the conical guide body 2 .

[0011] The nozzle 5 is fixed to the surface of the conical guide body 2 at the lower end of the steam channel 3 by threaded insertion or welding, and a threaded sealing ring is added to the threaded insertion or welding connection or a sealing treatment is performed after welding.

[0012] The scraper assembly 4 is fixed to the outside of the shell by elastic buckles, and the flange connection part 1 is a circular flange structure, and its cross section is an annular flat plate.

[0013] The de-icing and de-waxing device works in conjunction with a matching workbench, which includes a steam connection interface 8, a workbench platform 9, a sliding guide column 10 and a motor 11;

[0014] There are two sliding guide pillars 10, which are symmetrically arranged at both ends of the surface of the workbench platform 9. A steam connection interface 8 is set at the top between the sliding guide pillars 10. The steam connection interface 8 is powered by a motor 11 and moves on the sliding guide pillars 10.

[0015] The steam connection interface 8 is connected to the top of the flange connection part 1.

[0016] The scraper assembly 4 is composed of multiple scraper blades of the same specifications. Each individual blade adopts an arc-shaped spring blade and adopts an elastic scraper structure arranged in a ring. The scraper assembly 4 is an elastic metal sheet distributed in a ring shape, embedded in the groove on the surface of the conical guide body 2 and distributed along the inner wall of the wellhead, without the need for a support frame structure.

[0017] The high-temperature and high-pressure steam nozzles 5 are evenly arranged above and below the scraper assembly 4, and perform directional injection at an angle of 30°-60°. Injecting steam at an inclined angle can form a fan-shaped coverage area on the inner wall of the wellhead rather than a local point impact.

[0018] The guide head 7 is arranged at the bottom of the device, and the guide head 7 has a conical structure.

[0019] The insulating chamber 6 is arranged in the middle of the steam channel 3 and is isolated from the internal steam channel 3 by insulating material. A small high-temperature heat-resistant motor is arranged inside, and the motor output shaft is connected to the central support shaft of the scraper assembly 4 through a sealed coupling.

[0020] Beneficial effects of the present invention:

[0021] The rocket-shaped wellhead deicing and dewaxing device provided by the present invention has significant technical advantages and application value. First, the device has a compact structure and high integration. Through modular design, it realizes the synergistic effect of multiple functions such as high-temperature steam deicing, physical scraping, electric rotary propulsion and guided downhole, effectively solving the problems of low thermal efficiency, incomplete scraping, and unstable downhole in traditional operations. Secondly, the device adopts a conical guide structure and a built-in guide head, which can ensure the automatic centering and smooth advancement of the device during the wellhead insertion process, significantly reducing operational resistance and improving installation efficiency and safety.

[0022] The insulated chamber provides stable isolation from high-temperature steam, and a small, heat-resistant motor inside automatically drives the rotary scraping mechanism. This not only improves the device's operating efficiency and wax removal coverage, but also reduces the space and maintenance required by traditional mechanical linkages. The directional arrangement of the high-temperature, high-pressure steam nozzles further enhances the softening speed of the wax and ice layers, effectively synergizing physical scraping with thermal thawing to improve overall operating efficiency.

[0023] The supporting workbench features a stable structure, sliding guides, and a lift drive, enabling the dewaxing device to be lowered into the well at a consistent and precise speed, ensuring safe operations. The steam connection is simple, and the entire platform is highly adaptable, facilitating flexible deployment on site.

[0024] The overall system is easy to operate and has a high safety factor. It is particularly suitable for oil field scenarios that require high-frequency well start-up operations in extremely cold environments. The reasons are: the nozzles are arranged at an inclination angle of 30°-60°, which can quickly form a uniform heat field under low temperature conditions and accelerate the softening and melting of the wax and ice layer; the scraper assembly is actively driven to rotate by the built-in motor to ensure efficient and uniform scraping during high-frequency downhole operations; the quick-connect steam interface enables the steam hose to be quickly disassembled and assembled, shortening the preparation time; the insulated chamber ensures that the motor can maintain stable operation in alternating hot and cold environments, thereby ensuring the reliability and durability of the device. In summary, the present invention not only improves the automation level and safety of wellhead de-icing and de-waxing operations, but also has good economic efficiency, practicality and promotion value, and has broad engineering application prospects and industrialization potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the structure of the present invention.

[0026] Figure 2 It is a cross-sectional structural diagram of the present invention.

[0027] Figure 3 This is a structural diagram of the wellhead workbench supporting the present invention.

[0028] Reference numerals:

[0029] 1 flange connection, 2 conical guide body, 3 internal steam channel, 4 scraper assembly, 5 high-temperature and high-pressure steam nozzle, 6 insulation chamber, 7 guide head, 8 steam connection interface, 9 workbench platform, 10 sliding guide column, 11 motor. DETAILED DESCRIPTION

[0030] The present invention will be described in further detail below with reference to the accompanying drawings.

[0031] A wellhead deicing and dewaxing device of the present invention includes a device body and a matching workbench. The device body is installed to the wellhead through a flange connection part 1. Steam is introduced into the internal steam channel 3 through the steam interface 8 on the matching workbench, and steam is sprayed into the wellhead through the directionally arranged high-temperature and high-pressure nozzles 5 to heat and soften the waxed and frozen areas.

[0032] It includes a flange connection part 1, an insulating chamber 6, a conical guide body 2, and a guide head 7 connected in sequence; an internal steam channel 3 is set through the flange connection part 1, the insulating chamber 6, the conical guide body 2, and the guide head 7, and a scraper assembly 4 and a high-temperature and high-pressure steam nozzle 5 are set around the conical guide body 2;

[0033] A heat-insulating chamber 6 is provided between the flange connection portion 1 and the conical body guide 2 .

[0034] The flange connection part 1 and the conical guide body 2 are connected by bolts, and a pressure-resistant sealing gasket is provided on the joint surface to prevent steam leakage; the flange connection part 1 and the conical guide body 2 can also be manufactured by integral welding.

[0035] The steam channel 3 is welded integrally with the heat-insulating chamber 6 and the inner wall of the conical guide body 2 to ensure the sealing and mechanical strength of the steam channel.

[0036] The nozzle 5 is fixed to the surface of the conical guide body 2 at the lower end of the steam channel 3 by threaded insertion or welding to ensure smooth steam ejection without leakage. The threaded insertion or welded connection is equipped with a threaded sealing ring or sealed after welding.

[0037] The scraper assembly 4 is fixed to the outside of the shell by elastic buckles, and the structure is convenient and quick to disassemble and replace. The flange connection part 1 is a circular flange structure, and its cross section is an annular flat plate.

[0038] The de-icing and de-waxing device works in conjunction with a matching workbench, which includes a steam connection interface 8, a workbench platform 9, a sliding guide column 10 and a motor 11;

[0039] There are two sliding guide pillars 10, which are symmetrically arranged at both ends of the surface of the workbench platform 9. A steam connection interface 8 is set at the top between the sliding guide pillars 10. The steam connection interface 8 is powered by a motor 11 and moves on the sliding guide pillars 10.

[0040] The steam connection interface 8 is connected to the top of the flange connection part 1.

[0041] The scraper assembly 4 is composed of multiple scraper blades of the same specifications. Each individual blade adopts an arc-shaped spring blade and adopts an elastic scraper structure arranged in a ring. The scraper assembly 4 is an elastic metal sheet distributed in a ring shape, embedded in the groove on the surface of the conical guide body 2 and distributed along the inner wall of the wellhead, without the need for a support frame structure.

[0042] The high-temperature, high-pressure steam nozzles 5 are evenly arranged above and below the scraper assembly 4, spraying steam at an angle of 30°–60°. Injecting steam at this angle creates a fan-shaped coverage area on the wellhead inner wall, rather than a localized, point-like impact. This avoids concentrated erosion caused by vertical injection while ensuring sufficient steam diffusion along the wellbore surface, achieving comprehensive heating and softening of the wax and ice layers. Preheating and post-scraping of residual soft wax are performed before and after scraping, enhancing the descaling effect.

[0043] The guide head 7 is provided at the bottom of the device and has a conical structure, which helps the device to be centered and stably inserted into the wellhead pipe to prevent deflection and jamming. It can form a central guidance function in the initial stage of the device being lowered into the well.

[0044] The insulating chamber 6 is located in the middle of the steam channel 3 and is isolated from the internal steam channel 3 by an insulating material. A small, high-temperature, heat-resistant motor is housed within the chamber. The motor output shaft is connected to the central support shaft of the scraper assembly 4 via a sealed coupling. The coupling is made of a high-temperature, corrosion-resistant material such as stainless steel or a high-temperature alloy, and a double-layer heat-resistant oil seal prevents steam and impurities from entering the motor compartment.

[0045] When the motor drives the rotating shaft, it drives the entire scraper ring to rotate synchronously. Combined with the design of the thermally insulated chamber 6, it can operate stably and long-term in high-temperature and high-humidity environments. This structure achieves integrated electric control of the device's rotation function, eliminating the traditional external rotary drive system, making the device more compact, efficient, and reliable.

[0046] The steam connection interface 8 is located on the top or side of the workbench 9 to facilitate access to the on-site steam system. The steam connection interface 8 adopts a threaded joint structure, with a sealing ring on the inner wall of the interface. In combination with a high-temperature resistant fluororubber sealing ring and a stainless steel quick-connect shell, the interface can withstand the requirements of long-term use in high-temperature and high-pressure steam environments, ensuring a reliable connection and no leakage. The workbench platform 9 is a rigid frame structure with guide rails and slides on it. It can withstand the weight of the descaling device and the load of the steam pipeline connection, and has heat-resistant and non-slip properties. Sliding guide pillars 10 are located on both sides of the platform 9. In conjunction with the lifting motor and moving slider, the descaling device can be sent to the wellhead in a uniform and stable manner to avoid equipment damage or misoperation caused by rapid fall.

[0047] The workbench platform 9 is a metal structure with high-temperature heat insulation function, and is provided with an electric or manual sliding guide column assembly for assisting going down the well.

[0048] The steam connection interface 8 adopts a quick-connect joint structure, which facilitates the rapid installation and removal of the steam hose and improves working efficiency.

[0049] Specifically, when the device is ready for operation, the de-icing and de-waxing device is mounted on the workbench platform 9 and connected to the steam delivery hose. After the workbench motor 11 is activated, the device is slowly and evenly lowered into the well by the sliding guide post 10. At this point, the steam system begins to supply heat, and high-temperature, high-pressure steam flows through the steam channel into the high-temperature, high-pressure steam nozzles 5 surrounding the scraper assembly 4 for targeted spraying, achieving initial thawing.

[0050] The insulated chamber 6 in the center of the device's main body slowly rotates the scraper assembly 4 via a built-in small, high-temperature motor, allowing the elastic scraper to maintain close contact with the wellbore's inner wall for continuous scraping. This rotational motion is synchronized with the lowering of the wellbore, achieving a coupled cleaning process of physical scraping and steam softening. The insulated chamber effectively prevents thermal damage to the motor from high-temperature steam, ensuring reliable, long-term, continuous operation.

[0051] The conical guide head (7) at the bottom of the device ensures automatic centering and guidance during entry into the wellbore, preventing the scraper from deviating and scraping the wellbore wall. The entire descaling operation is completed in a closed and controlled environment, with operators only needing to monitor and adjust the speed from the ground platform.

[0052] After use, the device is slowly lifted back to the ground by controlling the guide column through the reverse drive motor, the steam supply is shut off, and the equipment is disassembled and cleaned and maintained to complete a complete operation process.

[0053] Working principle of the present invention:

[0054] The de-icing and de-waxing device is fixed to the matching steam connection interface 8 on the workbench through the flange connection part 1, and a reliable connection is achieved with the help of a bolt fastening structure, so that the device is firmly installed on the workbench platform 9, which is convenient for the guidance and operation of subsequent downhole operations; a layer of sealing gaskets that can withstand high temperature and high pressure conditions and work stably, such as metal-coated graphite gaskets or polytetrafluoroethylene gaskets, is embedded between the sealing surfaces of the docking.

[0055] During assembly, axial pressure is applied by tightening the connecting bolts, causing the sealing gasket to be uniformly compressed and tightly fitted to the sealing surfaces of the two flanges, thereby eliminating the slight gap between the contact surfaces and forming a continuous and complete sealing belt, ensuring the sealing reliability of high-temperature and high-pressure steam during transmission. The conical guide body 2 serves as an integral insertion guide structure, reducing resistance during device insertion and guiding the entire device to enter centered along the central axis of the wellbore, avoiding eccentric contact of the scraper with the wellbore wall, which may reduce efficiency or equipment wear. The internal steam channel 3 runs longitudinally along the central axis of the device, introducing high-temperature and high-pressure steam from the steam inlet and passing directly to the high-temperature and high-pressure steam nozzle 5 through the channel inside the conical guide body 2, forming a closed, continuous and stable steam transmission path. The internal steam channel 3 is a linear structure parallel to the device axis and can be made of thick-walled high-temperature resistant metal material, or the inner surface of the channel can be covered with a heat-resistant insulation layer to reduce heat loss during steam transmission. In order to further improve the thermal insulation performance, a double-layer structure or a heat-insulating interlayer can be set between the internal steam channel 3 and the external shell, so that the required temperature and pressure can be maintained when the steam is transported to the high-temperature and high-pressure steam nozzle 5, ensuring that the scraper assembly 4 has sufficient thermal energy support when working. After the steam passes through the axial channel, it is evenly ejected through the bottom nozzle 5. The connection between the nozzle 5 and the channel 3 can be threaded or short-tube butt welding, so that the steam channel and the nozzle are smoothly connected; the scraper assembly 4 is composed of a plurality of scraper blades of the same specification. Each individual blade adopts an arc-shaped spring blade, and an elastic scraper structure arranged in a ring is used to fit the inner wall of the wellhead for physical scraping. The scraper material can be made of high-temperature resistant and wear-resistant composite elastic metal, so that it can continuously scrape the wax layer and adapt to the deformation of the well wall during the rotation and propulsion process. The equal spacing and elastic design ensure that the scraper maintains proper contact with the inner wall, which can effectively scrape wax stains without getting stuck.

[0056] The present invention combines a rocket-shaped structure with a steam injection system, an annular scraper assembly, and an automatic downhole guide device to form a new type of wellhead operation equipment with a compact structure, convenient operation, efficient heating, and safety and reliability. This solves the problems of traditional wellhead deicing and dewaxing methods, such as cumbersome operation, low efficiency, poor thermal energy utilization, complex structure, and significant safety hazards. This embodiment has the characteristics of reasonable structure, safe operation, and strong adaptability. It is suitable for different wellhead sizes and complex low-temperature working conditions. While ensuring the de-waxing and de-icing effects, it significantly improves the operating efficiency and on-site safety factor.

[0057] This invention is used for deicing and dewaxing operations at wellheads and casing inlets in cold oilfields. Through a combination of physical scraping and high-temperature, high-pressure steam, it can quickly and efficiently remove wax and ice deposits from the inner walls of oil pipes, wellhead flanges, and related fittings, ensuring the normal production and safe operation of oil wells. This invention is suitable for scenarios such as continuous wellhead dewaxing, maintenance operations, and high-frequency unsealing of oil wells, and has broad engineering practical value and potential for widespread adoption.

Claims

1. A wellhead deicing and dewaxing device, characterized in that: The invention comprises a flange connection part (1), a heat-insulating chamber (6), a conical guide body (2), and a guide head (7) connected in sequence; an internal steam passage (3) is provided through the flange connection part (1), the heat-insulating chamber (6), the conical guide body (2), and the guide head (7); and a scraper assembly (4) and a high-temperature and high-pressure steam nozzle (5) are provided around the conical guide body (2); A heat-insulating chamber (6) is provided between the flange connection portion (1) and the conical body guide (2).

2. A wellhead deicing and dewaxing device according to claim 1, characterized in that: The flange connection part (1) and the conical flow guide (2) are connected by bolts, and a pressure-resistant sealing gasket is provided on the joint surface.

3. The wellhead deicing and dewaxing device according to claim 1, characterized in that: The steam channel (3), the heat-insulating chamber (6), and the inner wall of the conical guide body (2) are welded and formed into one piece.

4. A wellhead deicing and dewaxing device according to claim 1, characterized in that: The nozzle (5) is fixed to the surface of the conical guide body (2) at the lower end of the steam channel (3) by threaded insertion or welding, and a threaded sealing ring is added to the threaded insertion or welded connection or a sealing treatment is performed after welding.

5. The wellhead deicing and dewaxing device according to claim 1, characterized in that: The scraper assembly (4) is fixed to the outside of the shell by means of elastic buckles, and the flange connection portion (1) is a circular flange structure, and its cross section is in the shape of an annular flat plate.

6. The wellhead deicing and dewaxing device according to claim 1, characterized in that: The deicing and dewaxing device works in conjunction with a matching workbench, which includes a steam connection interface (8), a workbench platform (9), a sliding guide column (10) and a motor (11); There are two sliding guide pillars (10) symmetrically arranged at both ends of the surface of the workbench platform (9); a steam connection interface (8) is arranged at the top between the sliding guide pillars (10); the steam connection interface (8) is powered by a motor (11) and moves on the sliding guide pillars (10); The steam connection interface (8) is connected to the top of the flange connection part (1).

7. The wellhead deicing and dewaxing device according to claim 1, characterized in that: The scraper assembly (4) is composed of a plurality of scraper blades of the same specification, each individual blade adopts an arc-shaped spring blade, and adopts an elastic scraper structure arranged in a ring shape. The scraper assembly (4) is an elastic metal sheet distributed in a ring shape, embedded in the surface groove of the conical guide body (2) and distributed along the inner wall of the wellhead.

8. The wellhead deicing and dewaxing device according to claim 1, characterized in that: The high-temperature and high-pressure steam nozzles (5) are evenly arranged above and below the scraper assembly (4) and perform directional injection at an angle of 30°-60°. Injecting steam at an inclined angle can form a fan-shaped coverage area on the inner wall of the wellhead rather than a local point impact.

9. The wellhead deicing and dewaxing device according to claim 1, characterized in that: The guide head (7) is arranged at the bottom of the device, and the guide head (7) has a conical structure.

10. The wellhead deicing and dewaxing device according to claim 1, characterized in that: The heat-insulating chamber (6) is arranged in the middle of the steam channel (3) and is isolated from the internal steam channel (3) by a heat-insulating material. A small high-temperature heat-resistant motor is arranged inside the chamber, and the motor output shaft is connected to the central support shaft of the scraper assembly (4) through a sealed coupling.

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