Intelligent paraffin control and paraffin removal integrated sucker rod device

Abstract

The invention provides an intelligent paraffin control and paraffin removal integrated sucker rod device. The intelligent paraffin control and paraffin removal integrated sucker rod device structurally comprises a sucker rod main body serving as a carrier, the paraffin control system comprises a composite coating and a two-parameter sensor and is used for physical paraffin control and real-time monitoring; the inner wall cleaning device comprises a memory alloy doctor blade, a micro hydraulic push rod and a storage cover and is used for removing paraffin in a lossless manner; and the intelligent regulation and control system consists of a multi-parameter Internet of Things acquisition unit, a single chip microcomputer controller and a wireless transmission module, so that data acquisition, analysis and remote monitoring are realized. According to the device, physical paraffin control and intelligent paraffin removal are combined, pollution of chemical agents to stratums is avoided, energy consumption can be reduced through a self-adaptive regulation and control mechanism of the device, a rod pipe is protected through a lossless paraffin scraping design, the maintenance cost can be reduced through remote monitoring, and the device is suitable for exploitation of high-paraffin-content oil reservoirs.

Description

Technical Field

[0001] This application relates to the field of oil extraction equipment technology, and provides an intelligent integrated sucker rod device for preventing and removing wax. Background Technology

[0002] High-wax oil reservoirs refer to oil reservoirs with a high paraffin content in the crude oil. During the extraction process, as the crude oil is lifted from the formation to the surface, the wellbore temperature and pressure gradually decrease. When the crude oil temperature drops below its wax precipitation point (usually 40-60℃), the paraffin dissolved in the crude oil precipitates and crystallizes. These wax crystals easily adhere to the surface of the sucker rod and the inner wall of the tubing, forming a dense wax deposit layer. Wax deposition reduces the annular space between the rod and tubing, significantly increasing frictional resistance, thereby increasing the load on the pumping unit, reducing pump efficiency, and drastically increasing energy consumption. In severe cases, wax deposition can completely block the oil flow channel, causing accidents such as sucker rod jamming or pump seizure, resulting in unplanned production shutdowns, soaring maintenance costs, and even well abandonment.

[0003] To address the problem of wax deposition, existing technologies mainly focus on two aspects: chemical and mechanical. At the chemical level, a common method is to inject chemical agents, such as wax inhibitors, dispersants, or solvents, into the wellbore or formation. These techniques are typically implemented using surface dosing devices or downhole continuous dosing tools. At the mechanical level, physical wax removal methods are mainly employed, including: (1) mechanical scraping, using rigid metal scrapers to scrape the wax layer from the pipe wall as the rod moves; (2) thermal wax removal, such as hot washing, where high-temperature hot water or steam is injected into the annulus to melt the wax layer; or downhole electric heating, such as using heating cables to continuously heat the wellbore section. In addition, there is also a maintenance method of periodically removing the sucker rod string for surface wax removal.

[0004] However, the aforementioned existing technologies have many limitations. Chemical wax removal / dewaxing techniques require continuous or intermittent injection of chemicals, resulting in high operating costs. Furthermore, chemical residues may remain in the formation, causing pore blockage, formation contamination, and groundwater risks. Some chemicals are also corrosive, accelerating tubing aging. In mechanical wax scraping, the rigid scraper blades make hard contact with the tubing wall, easily scratching the pipe wall or sucker rod coating, leading to equipment damage or even perforation and leakage. Simultaneously, the scraper blades lack adaptability to changes in wax layer thickness; incomplete removal leaves residual wax, while excessive removal exacerbates wear. Thermal wax removal is extremely energy-intensive, and frequent thermal cycling can cause stress fatigue in the tubing string. Summary of the Invention

[0005] This application aims to address the problems of existing chemical wax prevention and mechanical wax removal methods, such as chemical contamination of the formation and incomplete mechanical wax scraping damaging the rod tube. It provides an intelligent integrated wax prevention and wax removal sucker rod device, comprising: a sucker rod body, a wax prevention system, and a wax removal system. The sucker rod body is equipped with the anti-wax system, which includes a composite coating and a dual-parameter sensor. The composite coating covers the outer surface of the sucker rod body and serves to repel water and conduct heat. The dual-parameter sensor is embedded inside the composite coating and attached to the outer wall of the sucker rod body, and is used to monitor the temperature data of the surface of the sucker rod body and the wax thickness data of the inner wall of the tubing in real time. The wax removal system includes an inner wall cleaning device, which includes a shape memory alloy scraper, a miniature hydraulic push rod, and a storage cover. The storage cover is fitted onto the lower end of the sucker rod body and is used to store the shape memory alloy scraper when not in operation. The miniature hydraulic push rod is disposed in the cavity of the storage cover and fixed to the lower end of the sucker rod body; The movable end of the micro hydraulic push rod is hinged to the root of the shape memory alloy scraper, which is used to unfold the shape memory alloy scraper in the working state and retract the shape memory alloy scraper in the non-working state. The miniature hydraulic push rod has a built-in sensor for real-time monitoring of the contact pressure data between the shape memory alloy scraper and the inner wall of the oil pipe.

[0006] In one feasible implementation, the anti-wax system further includes a low-frequency electromagnetic generator; The low-frequency electromagnetic generator is built into the cavity of the sucker rod body or embedded in the rod wall of the sucker rod body and is electrically connected to the dual-parameter sensor. The low-frequency electromagnetic generator is used to emit low-frequency signals to oscillate and disrupt the wax crystal structure.

[0007] One feasible implementation also includes: an intelligent control system; The intelligent control system includes a multi-parameter Internet of Things (IoT) acquisition unit and a single-chip microcomputer controller. The multi-parameter IoT acquisition unit is electrically connected to the built-in sensors of the dual-parameter sensor and the miniature hydraulic push rod, respectively, and has acquired adjustment data; the adjustment data includes: temperature data, wax thickness data, and contact pressure data; The output of the multi-parameter IoT acquisition unit is communicatively connected to the input of the microcontroller, and transmits the adjustment data to the microcontroller. The output terminal of the single-chip microcomputer controller is communicatively connected to the control terminal of the low-frequency electromagnetic generator and the thrust adjustment terminal of the micro hydraulic push rod, respectively. The microcontroller analyzes and processes the adjustment data based on a preset reservoir database, generates adjustment commands, and sends the adjustment commands to the control terminal of the low-frequency electromagnetic generator and the thrust adjustment terminal of the micro hydraulic push rod. The adjustment commands include: adjusting the oscillation frequency of the low-frequency electromagnetic generator, adjusting the thrust threshold of the micro hydraulic push rod, and adjusting the extension and retraction period of the shape memory alloy scraper.

[0008] One feasible implementation also includes: a wireless transmission module; The microcontroller is electrically connected to the wireless transmission module. The wireless transmission module transmits the adjustment data and adjustment commands to the ground monitoring platform via LoRa or 4G network, and the ground monitoring platform is used for remote monitoring.

[0009] In one feasible implementation, the end of the shape memory alloy scraper away from the micro hydraulic push rod is wrapped with a polyurethane wear-resistant layer, the polyurethane wear-resistant layer having a thickness of 2-3 mm. When the shape memory alloy scraper unfolds, it conforms to the inner wall of the oil pipe in an arc shape, and when it retracts, it curls up and is stored in the cavity of the storage cover.

[0010] In one feasible implementation, multiple dual-parameter sensors and low-frequency electromagnetic generators are provided and arranged at equal intervals along the axial direction of the sucker rod body.

[0011] In one feasible implementation, the composite coating is composed of an epoxy resin matrix, aluminum nitride nanoparticles, and fluorosilane-modified nano-SiO2. The composite coating has a thickness of 0.1-0.3 mm, an aluminum nitride nanoparticle content of 20%-30%, and a fluorosilane-modified nano-SiO2 content of 5%-10%.

[0012] In one feasible implementation, the sucker rod body includes: an upper connecting rod, a connecting clamp, a pin, and a lower connecting rod; The top end of the upper connecting rod is connected to the oil pumping unit, and the bottom end of the lower connecting rod is connected to the oil pump. The upper connecting rod, the connecting hoop, and the lower connecting rod are all hollow metal rods. The connecting hoop is sleeved on the bottom end of the upper connecting rod and the top end of the lower connecting rod, and is fixedly connected to the upper connecting rod and the lower connecting rod by the pin.

[0013] In one feasible implementation, the pin is an axial limiting pin, and the two ends of the pin are clearance-fitted with the pin holes of the upper connecting rod and the lower connecting rod. The pin is provided with an annular limiting boss in the middle, and the limiting boss forms a ±5° swing gap with the side wall of the pin hole of the lower connecting rod. The pin is interference-fitted with the pin hole of the upper connecting rod. When the lower connecting rod rotates around the axis of the pin, the limiting boss contacts and limits the pin hole sidewall of the lower connecting rod.

[0014] The beneficial effects of the intelligent integrated wax prevention and removal sucker rod device provided in this application are as follows: 1. By combining the thermal conductivity and hydrophobicity of the composite coating with the destructive effect of the low-frequency electromagnetic generator on the wax crystal structure, the precipitation and adhesion of wax are inhibited from the source.

[0015] 2. The intelligent control system can dynamically adjust the anti-wax and wax removal strategies based on real-time monitoring of multiple parameters such as temperature, wax thickness, and pressure. It activates the corresponding functions only when needed, significantly reducing energy consumption.

[0016] 3. The entire wax removal process is completely free of chemical agents, avoiding formation contamination and rod / tubing corrosion. Furthermore, the wax removal process does not scratch the inner wall of the tubing, effectively extending the service life of the sucker rod and tubing.

[0017] 4. Real-time remote monitoring and early warning of downhole working conditions are achieved through the wireless transmission module, which greatly reduces the frequency and intensity of manual inspections and reduces overall maintenance costs. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the implementation of the invention and, together with the description, serve to explain the principles of the embodiments of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0019] Figure 1 This is a three-dimensional structural schematic diagram of an integrated intelligent wax prevention and removal sucker rod device, as shown in an exemplary embodiment of this application. Figure 2 A schematic diagram illustrating the extension of a shape memory alloy scraper, as shown in an exemplary embodiment of this application; Figure 3 This is a schematic diagram illustrating the retraction of a shape memory alloy scraper, as shown in an exemplary embodiment of this application. Figure 4 This is a schematic diagram of the structure of a low-frequency electromagnetic generator shown in an exemplary embodiment of this application.

[0020] Attached image captions: 1-Upper connecting rod; 2-Connecting clamp; 3-Pin; 4-Lower connecting rod; 5-Inner wall cleaning device; 6-Oil storage tank; 7-Plug; 11-Composite coating; 12-Low frequency electromagnetic generator; 51-Memory alloy scraper; 52-Hydraulic push rod; 53-Storage cover; 111-Dual parameter sensor. Detailed Implementation

[0021] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the embodiments of the invention will be more comprehensive and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a full understanding of how embodiments of the invention are carried out.

[0022] During the extraction of high-wax oil reservoirs, the precipitated paraffin wax adheres to the inner walls of the sucker rod and tubing as the crude oil temperature decreases. This increases frictional resistance, reduces pumping efficiency, and can lead to serious pump jamming accidents. Existing technologies are mostly chemical and mechanical, but these suffer from problems such as chemical contamination of the formation and incomplete mechanical wax scraping that damages the sucker rod and tubing.

[0023] To address the aforementioned problems, this application provides an intelligent integrated anti-wax and wax-removing sucker rod device, referring to... Figures 1-4 As shown, the system mainly includes a sucker rod body, an anti-wax system, and a wax removal system. The sucker rod body, as the basic carrier of the entire device, is responsible for transmitting the reciprocating motion power of the pumping unit. The anti-wax system, located on the sucker rod body, mainly consists of a composite coating 11 and a dual-parameter sensor 111. The composite coating 11 completely covers the outer surface of the sucker rod body, and its function is to prevent paraffin wax from adhering to the sucker rod body through efficient thermal conductivity and superhydrophobicity. Specifically, the composite coating 11 uses an epoxy resin matrix, aluminum nitride nanoparticles as thermally conductive fillers, and 5%-10% fluorosilane-modified nano-SiO2 to achieve hydrophobicity.

[0024] A dual-parameter sensor 111 is embedded inside the composite coating 11 and tightly adhered to the outer wall of the sucker rod body. Its function is to monitor the temperature data of the surface of the sucker rod body and the wax thickness data of the inner wall of the tubing in real time.

[0025] The dewaxing system includes an inner wall cleaning device 5, which further includes a shape memory alloy scraper 51, a miniature hydraulic push rod 52, and a storage cover 53. The storage cover 53 is fitted onto the lower end of the sucker rod body, and its main function is to store the shape memory alloy scraper 51 in the non-working state to protect it from crude oil erosion and damage. The miniature hydraulic push rod 52 is housed in the cavity of the storage cover 53 and fixed to the lower connecting rod 4. Its movable end is hinged to the root of the shape memory alloy scraper 51, allowing the scraper 51 to be deployed in the working state, pressing it tightly against the inner wall of the tubing for dewaxing, and retracted in the non-working state. The miniature hydraulic push rod 52 has a built-in sensor for real-time monitoring of the contact pressure data between the shape memory alloy scraper 51 and the inner wall of the tubing, ensuring that the inner wall of the tubing is not damaged during the dewaxing process.

[0026] In actual operation, the sucker rod body reciprocates up and down under the drive of the pumping unit. During this movement, the composite coating 11, through its highly efficient thermal conductivity, evenly conducts the frictional heat generated by the sucker rod body movement to the rod surface, increasing the crude oil temperature and thus inhibiting paraffin precipitation. Simultaneously, the superhydrophobicity of the composite coating 11 reduces the adhesion of paraffin molecules to the rod surface, further reducing paraffin deposition. A dual-parameter sensor 111 monitors the temperature data of the sucker rod body surface and the wax thickness data of the tubing inner wall in real time. When the temperature is below the wax precipitation point of the crude oil, the system will activate anti-wax measures according to preset logic. Simultaneously, if the wax thickness data reaches a preset threshold, the system will initiate a wax removal operation.

[0027] During the wax removal process, the micro hydraulic push rod 52 unfolds the shape memory alloy scraper 51 according to the instructions of the microcontroller, making it adhere tightly to the inner wall of the oil pipe. The shape memory alloy scraper 51 scrapes off the wax layer on the inner wall of the oil pipe as the sucker rod body moves up and down. The built-in sensor monitors the contact pressure between the scraper and the inner wall of the oil pipe in real time. If the contact pressure exceeds the safe range, the thrust of the micro hydraulic push rod 52 is controlled and adjusted to ensure that the inner wall of the oil pipe is not damaged during the wax removal process.

[0028] This embodiment utilizes the thermal conductivity and hydrophobicity of the composite coating 11 for physical wax prevention, and mechanical wax removal via a shape memory alloy scraper 51. The embodiment employs a combination of the shape memory alloy scraper 51 and a micro hydraulic push rod 52, enabling dynamic adjustment of the contact pressure between the scraper and the tubing inner wall. It features intelligent monitoring and adaptive adjustment capabilities; through a combination of a dual-parameter sensor 111 and a single-chip microcomputer controller, it can monitor the sucker rod surface temperature and tubing inner wall wax thickness data in real time, dynamically adjusting the wax prevention and removal strategies, reducing manual inspection and maintenance costs, and improving oil production efficiency. It is suitable for pumping well production in onshore and offshore high-wax reservoirs, especially for deep wells, ultra-deep wells with high wax precipitation temperatures and rapid wax deposition rates, and complex high-wax reservoirs with dynamically changing water cuts.

[0029] In some embodiments of this application, the anti-waxing system further includes a low-frequency electromagnetic generator 12. The low-frequency electromagnetic generator 12 is built into the cavity of the sucker rod body or embedded in the rod wall of the sucker rod body, and is electrically connected to the dual-parameter sensor 111. The main function of the low-frequency electromagnetic generator 12 is to emit low-frequency electromagnetic oscillations, which disrupt the orderly arrangement of wax crystal molecules through an alternating magnetic field, inhibiting the growth of wax crystals, thereby achieving physical anti-waxing.

[0030] The magnetic field strength and frequency of the low-frequency electromagnetic generator 12 can be dynamically adjusted by a microcontroller based on the wax thickness and temperature data collected by the dual-parameter sensor 111. The low-frequency electromagnetic field generated by the low-frequency electromagnetic generator 12 can penetrate into the crude oil medium, act on the wax molecules, and interfere with their normal crystallization process, making it difficult for wax crystals to aggregate into large particles and deposit on the inner wall of the tubing. At the same time, the design of the low-frequency electromagnetic generator 12 fully considers compatibility with the sucker rod body. Its installation position and method will not affect the normal strength of the sucker rod and downhole operations, and it has good temperature resistance, pressure resistance, and corrosion resistance to adapt to the complex and harsh working environment downhole.

[0031] During actual operation, the dual-parameter sensor 111 monitors the temperature data of the sucker rod body surface and the wax thickness data of the tubing inner wall in real time. When the temperature is lower than the wax precipitation point of the crude oil, the low-frequency electromagnetic generator 12 can be activated according to the preset logic. The low-frequency electromagnetic generator 12 emits low-frequency electromagnetic oscillations, which disrupt the orderly arrangement of wax crystal molecules through an alternating magnetic field, inhibiting the growth of wax crystals and thus preventing paraffin from agglomerating on the sucker rod body.

[0032] If the wax thickness reaches a preset threshold, in addition to activating the low-frequency electromagnetic generator 12, the system will also initiate a wax removal operation. The micro hydraulic push rod 52 unfolds the shape memory alloy scraper 51 according to the instructions of the microcontroller controller to perform the wax removal operation. During the wax removal process, the low-frequency electromagnetic generator 12 can continue to operate to further suppress the formation and growth of wax crystals, thereby improving the wax removal effect.

[0033] Compared to traditional high-frequency electromagnetic heating methods, the low-frequency electromagnetic oscillation used in this embodiment consumes less energy and is more energy-efficient. The low-frequency electromagnetic generator 12 can work in conjunction with the wax removal system to improve the overall wax prevention and removal effect. This achieves the goal of efficient, energy-saving, and pollution-free wax prevention and removal.

[0034] In some embodiments of this application, the device further includes an intelligent control system, which consists of a multi-parameter IoT acquisition unit and a microcontroller. The multi-parameter IoT acquisition unit is located at a suitable position inside or outside the sucker rod body to stably collect key data such as temperature, wax thickness, and contact pressure, and is electrically connected to the dual-parameter sensor 111 and the sensor built into the miniature hydraulic push rod 52. The microcontroller receives real-time data transmitted by the acquisition unit, analyzes and processes it according to a preset reservoir database and algorithm model, and then generates control commands.

[0035] During system operation, the multi-parameter IoT acquisition unit continuously acquires downhole operating condition data and transmits it to the microcontroller controller. When the temperature data is lower than the wax precipitation point of crude oil, the microcontroller controller adjusts the oscillation frequency of the low-frequency electromagnetic generator 12 accordingly. By enhancing or weakening the electromagnetic oscillation, it disrupts the wax crystal structure, inhibiting paraffin precipitation and deposition. If the wax thickness data reaches or exceeds a preset threshold, the microcontroller controller adjusts the thrust threshold of the micro hydraulic push rod 52, allowing the shape memory alloy scraper 51 to scrape off the wax layer on the inner wall of the tubing with appropriate force, while avoiding damage to the tubing wall. It can also adjust the scraper extension and retraction cycle according to the wax layer distribution to improve the wax removal efficiency. During the wax removal operation, the built-in sensor of the micro hydraulic push rod 52 monitors the contact pressure between the scraper and the tubing wall in real time and feeds back the data. Once the pressure exceeds the safe range, the microcontroller controller immediately adjusts the push rod thrust to ensure safe and effective operation.

[0036] The intelligent control system in this embodiment achieves adaptive adjustment of the wax prevention and removal strategy through multi-parameter acquisition and dynamic analysis and decision-making, thereby improving oil production efficiency by suppressing wax deposition in real time and reducing rod and tubing friction resistance; it also reduces manual intervention costs by automatically responding to changes in operating conditions. Simultaneously, it enhances environmental adaptability by allowing the preset model to match different reservoir conditions. Furthermore, it improves operational safety, as controlled contact pressure effectively prevents damage to the tubing inner wall. The collaborative operation between systems ensures the stability and reliability of the pumping process.

[0037] In some embodiments of this application, the intelligent control system further includes a wireless transmission module. This module interacts with the microcontroller controller to transmit control data and commands to the ground monitoring platform. The ground monitoring platform, acting as a remote monitoring center, receives and displays the data sent by the wireless transmission module in real time. It also has a remote command sending function, capable of sending control commands to the microcontroller controller to regulate the anti-wax and wax removal strategies.

[0038] During system operation, the wireless transmission module continuously transmits adjustment data such as temperature, wax thickness, and contact pressure collected by the multi-parameter IoT acquisition unit, as well as adjustment commands generated by the microcontroller controller, to the ground monitoring platform via LoRa or 4G network. Upon receiving the data, the ground monitoring platform immediately displays and analyzes it, presenting the downhole operating conditions data intuitively through charts and curves to help staff understand the on-site situation. Furthermore, it utilizes data analysis functions to statistically analyze historical data, providing support for optimizing wax prevention and removal strategies.

[0039] Understandably, when workers discover abnormal downhole conditions or need to adjust strategies, they can send remote commands to the microcontroller controller via the surface monitoring platform. Upon receiving the commands, the microcontroller controller will adjust the anti-wax and wax removal measures accordingly, ensuring safe and efficient operations. The collaboration between the wireless transmission module and the surface monitoring platform enables real-time data exchange and remote control between the downhole and surface, allowing workers to promptly identify and address problems, thus improving the intelligence level and emergency response capabilities of oil production operations.

[0040] In some embodiments of this application, the end of the shape memory alloy scraper 51 away from the micro hydraulic push rod 52 is wrapped with a polyurethane wear-resistant layer with a thickness of 2-3 mm.

[0041] When the shape memory alloy scraper 51 is unfolded, the polyurethane wear-resistant layer is arc-shaped and closely adheres to the inner wall of the oil pipe to ensure the wax scraping effect. In the contracted state, it is curled up and stored in the cavity of the storage cover 53 to avoid unnecessary friction between the sucker rod and the inner wall of the oil pipe during the up and down movement.

[0042] During system operation, when the dual-parameter sensor 111 detects that the wax layer thickness on the inner wall of the oil pipe reaches a preset threshold, the microcontroller controller issues a command, and the micro hydraulic pusher 52 pushes the shape memory alloy scraper 51 to unfold. Because the scraper is wrapped with a polyurethane wear-resistant layer, friction with the inner wall of the oil pipe is effectively reduced during unfolding and wax scraping, avoiding damage to the oil pipe and the scraper. After wax scraping is completed, the micro hydraulic pusher 52 retracts, and the shape memory alloy scraper 51 automatically curls up and is stored in the storage cover 53 under its own characteristics, waiting for the next wax scraping command.

[0043] This embodiment achieves low friction and low damage during the wax removal process by combining structural optimization and material properties of the shape memory alloy scraper 51. The arc-shaped design of the scraper conforms to the inner wall of the oil pipe, ensuring thorough and effective wax removal and improving scraping efficiency. The polyurethane wear-resistant layer reduces friction, extends the service life of the scraper, reduces maintenance frequency and costs, and overall ensures the effectiveness of the wax removal operation and the durability of the equipment.

[0044] In some embodiments of this application, multiple dual-parameter sensors 111 and low-frequency electromagnetic generators 12 are provided and arranged at equal intervals along the axial direction of the sucker rod body. Each sucker rod has 5-10 sets evenly arranged according to the well depth and wax deposition characteristics. Each set includes dual-parameter sensors 111 and low-frequency electromagnetic generators 12, so as to realize comprehensive monitoring and control of the wax layer thickness and temperature on the inner wall of the tubing.

[0045] During system operation, the dual-parameter sensor 111 monitors the temperature of the inner wall of the tubing and the thickness of the wax layer in real time, transmitting the data to the microcontroller controller. When the temperature in a certain area is lower than the wax precipitation point or the wax layer thickness exceeds the threshold, the microcontroller controller activates the low-frequency electromagnetic generator 12 in the corresponding area. The alternating magnetic field destroys the wax crystal structure to inhibit precipitation or remove the deposited wax layer. The sensors and electromagnetic generators in other areas continue to monitor, ensuring the anti-wax effect throughout the tubing.

[0046] This embodiment achieves comprehensive monitoring and precise control through multi-point deployment and a local response mechanism. Its beneficial effects are as follows: multi-point monitoring covers the entire oil pipe, preventing pump jamming accidents caused by excessively thick local wax layers and improving wax prevention; local control only activates the electromagnetic generator when needed, reducing unnecessary energy consumption and achieving energy saving; comprehensive monitoring and precise response enhance the stability and reliability of system operation.

[0047] In some embodiments of this application, the composite coating 11 covers the surface of the sucker rod body and is composed of an epoxy resin matrix, aluminum nitride nanoparticles and fluorosilane-modified nano-SiO2, with a thickness of 0.1-0.3 mm. The aluminum nitride nanoparticle content is 20%-30% and the fluorosilane-modified nano-SiO2 content is 5%-10%, which serves to conduct heat and prevent waxing.

[0048] Understandably, the epoxy resin matrix, as a coating, provides excellent adhesion and mechanical strength, ensuring that the composite coating can bond tightly to the surface of the sucker rod and withstand the complex downhole working environment. Aluminum nitride nanoparticles possess excellent thermal conductivity, significantly improving the coating's thermal conductivity and accelerating the transfer of heat from the sucker rod to the surrounding crude oil, helping to maintain the crude oil temperature above the wax precipitation point and reducing wax precipitation at its source. Meanwhile, fluorosilane-modified nano-SiO2 endows the coating with excellent hydrophobic properties and extremely low surface energy, making it difficult for wax molecules in the crude oil to adhere and deposit on the sucker rod surface. It also reduces the flow resistance of crude oil on the sucker rod surface, further enhancing the anti-wax effect. This synergistic effect of the composite coating not only effectively inhibits wax deposition on the sucker rod surface but also improves the sucker rod's wear and corrosion resistance, extending its service life.

[0049] The preparation process of this composite coating is as follows: First, epoxy resin matrix and aluminum nitride nanoparticles are mixed evenly in a certain proportion to form a thermally conductive filler mixture. Then, fluorosilane-modified nano-SiO2 is added. After high-speed stirring and ultrasonic treatment, the nanoparticles are evenly dispersed. Finally, the mixture is sprayed or brushed onto the surface of the sucker rod and cured. During operation, the composite coating, with its high thermal conductivity, evenly conducts the frictional heat generated by the movement of the sucker rod to the rod surface to increase the crude oil temperature and inhibit wax crystal precipitation. At the same time, its super hydrophobicity reduces the adhesion of paraffin molecules to the rod, further reducing wax layer formation.

[0050] In some embodiments of this application, the sucker rod body includes an upper connecting rod 1, a connecting clamp 2, a pin 3, and a lower connecting rod 4. The top end of the upper connecting rod 1 is connected to the pumping unit, and the bottom end of the lower connecting rod 4 is connected to the pumping pump. All three are hollow metal rods. The connecting clamp 2 is sleeved on the bottom end of the upper connecting rod 1 and the top end of the lower connecting rod 4, and is fixedly connected to the upper connecting rod 1 and the lower connecting rod 4 by the pin 3, thereby ensuring a stable connection between the upper connecting rod 1 and the lower connecting rod 4, while allowing a certain small angle to adapt to the bending deformation of the sucker rod downhole.

[0051] Furthermore, the bottom outer wall of the upper connecting rod 1 is provided with an external thread section, and the top inner wall of the lower connecting rod 4 is provided with an internal thread section. The inner wall of the connecting clamp 2 is provided with an upper internal thread that matches the external thread section of the upper connecting rod 1 and a lower internal thread that matches the internal thread section of the lower connecting rod 4. During assembly, the pin 3 is first inserted into the pin hole of the upper connecting rod 1 to form an interference fit. Then, the top of the lower connecting rod 4 is fitted into the lower end of the connecting clamp 2 and tightened so that the pin hole of the lower connecting rod 4 is aligned with the free end of the pin 3. Subsequently, the free end of the pin 3 is inserted into the pin hole of the lower connecting rod 4. At this time, the two sides of the annular limiting boss and the upper and lower side walls of the pin hole of the lower connecting rod 4 respectively retain a preset swing gap. This gap ensures that when the lower connecting rod 4 is subjected to downhole lateral force, it can swing around the axis of the pin 3 at a certain angle, avoiding stress concentration caused by rigid connection. Meanwhile, the upper and lower internal threads of the connecting clamp 2 are tightly engaged with the threaded sections of the upper and lower connecting rods, forming a double fixing structure. This structure not only bears the main axial tensile force through the threaded connection, but also restricts radial displacement through the limiting effect of the pin 3, which significantly improves the structural stability and fatigue resistance of the sucker rod body under complex working conditions.

[0052] The pumping unit drives the entire sucker rod body to reciprocate up and down via the upper connecting rod 1. The lower connecting rod 4 transmits the motion to the pumping unit, enabling the suction and discharge of crude oil. The sucker rod body utilizes a modular structure design. A hollow metal rod ensures efficient motion transmission, while the fixed connection between the connecting clamp 2 and the pin 3 maintains structural stability. A micro-angle adaptive design enhances adaptability to complex downhole environments, and the modular form simplifies installation, disassembly, and maintenance. The benefits are reflected in improved transmission efficiency due to the stable connection and hollow rod body, reduced pump jamming due to angle adaptability, and easier maintenance due to the modular design, resulting in highly efficient and stable crude oil extraction.

[0053] In some embodiments of this application, the pin 3 is an axial limiting pin, with its two ends having clearance fit with the pin holes of the upper connecting rod 1 and the lower connecting rod 4, and an annular limiting boss provided in the middle. The limiting boss and the side wall of the pin hole of the lower connecting rod 4 form a ±5° swing gap. The pin 3 has an interference fit with the pin hole of the connecting hoop 2. When the lower connecting rod 4 rotates around the pin axis, the limiting boss contacts and limits the pin hole of the lower connecting rod 4, thereby ensuring a stable connection between the upper connecting rod 1 and the lower connecting rod 4, while allowing for small angle self-adaptation.

[0054] Specifically, during oil pumping, when formation conditions are complex or the wellbore trajectory is curved, the lower connecting rod 4 will be subjected to lateral friction or impact loads from the well wall. At this time, the pre-set swing gap between the pin hole of the lower connecting rod 4 and the annular limiting boss allows the lower connecting rod 4 to swing slightly by ±5° relative to the upper connecting rod 1 around the axis of the pin 3. This swing effectively buffers the impact from lateral forces, avoiding the rapid accumulation of stress at the connection point as is common in traditional rigid connections.

[0055] Meanwhile, the upper and lower internal threads of the connecting clamp 2 always maintain a tight engagement with the threaded sections of the upper and lower connecting rods, ensuring stable transmission of axial tensile force during oscillation. The pin 3, while limiting excessive radial displacement, ensures the initial strength of the connection through its interference fit with the pin hole, preventing loosening during long-term reciprocating motion. Through this structural design, the sucker rod body can better adapt to the complex and changing working conditions downhole, reducing failures such as fractures and deformations caused by stress concentration, thereby extending the service life of the sucker rod and reducing maintenance costs in oilfield operations.

[0056] In some embodiments of this application, the wax removal system further includes an oil storage tank 6 and a plug 7. The oil storage tank 6 is tightly connected to the bottom end of the upper connecting rod 1 by a threaded connection, which is both stable and easy to disassemble for periodic cleaning of accumulated wax. Its volume can accommodate the scraped wax blocks between two cleaning cycles, depending on the wax deposition rate and scraping frequency of the oil well. The plug 7 is screwed onto the bottom of the oil storage tank 6, designed to ensure a tight seal to prevent leakage of crude oil and wax blocks, while also facilitating opening and cleaning. Its lower end is connected to the inlet of the oil pump, allowing the scraped wax blocks to be extracted from the wellbore along with the crude oil.

[0057] During system operation, the shape memory alloy scraper 51, driven by the hydraulic push rod 52, unfolds to scrape off the wax layer on the inner wall of the oil pipe. The scraped wax blocks fall into the oil storage tank 6 due to gravity. As the wax blocks accumulate, the space inside the oil storage tank 6 decreases. The sealing design of the plug 7 ensures that crude oil and wax blocks do not leak, guaranteeing continuous and stable oil production operations. When the ground monitoring platform determines, based on sensor data, that the wax blocks in the oil storage tank 6 are approaching or have reached the upper limit of capacity, it issues a cleaning command. Upon receiving the command, the operator stops the pumping unit, uses a special tool to rotate and remove the plug 7, collects and processes the outflowing wax blocks and some crude oil, reinstalls the plug 7 after cleaning, ensures a seal, and then restarts the pumping unit to resume operations. To further improve efficiency, an automatic discharge device can be installed at the bottom of the oil storage tank 6, enabling automatic discharge and collection of wax blocks through ground control, reducing manual intervention.

[0058] Based on the above embodiments, the overall usage process of the intelligent anti-wax and wax-removing integrated sucker rod device provided in this application is as follows: First, the sucker rod reciprocates up and down under the drive of the pumping unit. The composite coating utilizes high thermal conductivity to transfer frictional heat from the rod body to maintain the crude oil temperature, while its superhydrophobicity reduces wax adhesion. Simultaneously, multiple dual-parameter sensors are spaced apart along the rod's axial direction to monitor the sucker rod surface temperature and the wax thickness on the tubing inner wall in real time. This data is collected by a multi-parameter IoT acquisition unit and transmitted to a microcontroller for analysis and processing.

[0059] The microcontroller makes decisions based on a preset reservoir database and algorithm model: if the monitored temperature is below the wax precipitation point of the crude oil, it activates the corresponding low-frequency electromagnetic generator to assist in coating anti-waxing; if the monitored wax thickness reaches a preset threshold, it generates a wax removal command. After the wax removal command is issued, the microcontroller controls the micro hydraulic push rod to push the shape memory alloy scraper out of the storage cover. The scraper adheres to the inner wall of the tubing and scrapes off the wax layer as the sucker rod moves. During wax scraping, the built-in sensor of the micro hydraulic push rod monitors the contact pressure and provides feedback, and the microcontroller dynamically adjusts the thrust to achieve non-destructive wax removal. The scraped wax blocks fall into the oil storage tank and can be pumped out of the wellbore with the crude oil or cleaned periodically.

[0060] The device's operating data and control commands are exchanged in real time with the ground monitoring platform via a wireless transmission module. The ground platform can remotely monitor downhole conditions and allow for manual intervention. The microcontroller adaptively adjusts the electromagnetic generator oscillation frequency, hydraulic push rod thrust threshold, and scraper action cycle based on multi-dimensional data and preset models to match different reservoir conditions.

[0061] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the disclosure in the specification and the embodiments. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein.

Claims

1. A smart integrated anti-wax and wax-removing sucker rod device, characterized in that, include: Sucker rod body, anti-wax system and dewaxing system; The sucker rod body is provided with the anti-wax system, which includes a composite coating (11) and a dual-parameter sensor (111). The composite coating (11) covers the outer surface of the sucker rod body and serves to repel water and conduct heat. The dual-parameter sensor (111) is embedded inside the composite coating (11) and attached to the outer wall of the sucker rod body, and is used to monitor the temperature data of the surface of the sucker rod body and the wax thickness data of the inner wall of the tubing in real time. The wax removal system includes an inner wall cleaning device (5), which includes a shape memory alloy scraper (51), a micro hydraulic push rod (52), and a storage cover (53). The storage cover (53) is fitted onto the lower end of the sucker rod body and is used to store the shape memory alloy scraper (51) when not in operation. The miniature hydraulic push rod (52) is disposed in the cavity of the storage cover (53) and fixed to the lower end of the sucker rod body; The movable end of the micro hydraulic push rod (52) is hinged to the root of the shape memory alloy scraper (51) for unfolding the shape memory alloy scraper (51) in the working state and retracting the shape memory alloy scraper (51) in the non-working state. The miniature hydraulic push rod (52) has a built-in sensor for real-time monitoring of the contact pressure data between the shape memory alloy scraper (51) and the inner wall of the oil pipe.

2. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 1, characterized in that, The anti-wax system also includes a low-frequency electromagnetic generator (12). The low-frequency electromagnetic generator (12) is built into the cavity of the sucker rod body or embedded in the rod wall of the sucker rod body and is electrically connected to the dual-parameter sensor (111). The low-frequency electromagnetic generator (12) is used to emit low frequencies to oscillate and destroy the wax crystal structure.

3. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 2, characterized in that, Also includes: Intelligent control system; The intelligent control system includes a multi-parameter Internet of Things (IoT) acquisition unit and a single-chip microcontroller. The multi-parameter IoT acquisition unit is electrically connected to the built-in sensors of the dual-parameter sensor (111) and the micro hydraulic push rod (52) to acquire adjustment data; the adjustment data includes: temperature data, wax thickness data and contact pressure data; The output of the multi-parameter IoT acquisition unit is communicatively connected to the input of the microcontroller, and transmits the adjustment data to the microcontroller. The output terminal of the single-chip microcomputer controller is communicatively connected to the control terminal of the low-frequency electromagnetic generator (12) and the thrust adjustment terminal of the micro hydraulic push rod (52); The single-chip microcomputer controller analyzes and processes the adjustment data based on the preset reservoir database, generates adjustment instructions, and sends the adjustment instructions to the control terminal of the low-frequency electromagnetic generator (12) and the thrust adjustment terminal of the micro hydraulic push rod (52); The adjustment commands include: adjusting the oscillation frequency of the low-frequency electromagnetic generator (12), adjusting the thrust threshold of the micro hydraulic push rod (52), and adjusting the extension and retraction period of the memory alloy scraper (51).

4. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 3, characterized in that, Also includes: Wireless transmission module; The microcontroller is electrically connected to the wireless transmission module. The wireless transmission module transmits the adjustment data and adjustment commands to the ground monitoring platform via LoRa or 4G network, and the ground monitoring platform is used for remote monitoring.

5. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 1, characterized in that, The end of the shape memory alloy scraper (51) away from the micro hydraulic push rod (52) is wrapped with a polyurethane wear-resistant layer, the thickness of which is 2-3mm; When the shape memory alloy scraper (51) unfolds, it fits the inner wall of the oil pipe in an arc shape, and when it contracts, it curls up and is stored in the cavity of the storage cover (53).

6. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 1, characterized in that, Multiple dual-parameter sensors (111) and low-frequency electromagnetic generators (12) are provided and are arranged at equal intervals along the axial direction of the sucker rod body.

7. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 1, characterized in that, The composite coating (11) is composed of an epoxy resin matrix, aluminum nitride nanoparticles and fluorosilane-modified nano-SiO2. The composite coating (11) has a thickness of 0.1-0.3 mm, an aluminum nitride nanoparticle content of 20%-30%, and a fluorosilane-modified nano-SiO2 content of 5%-10%.

8. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 1, characterized in that, The main body of the sucker rod includes: an upper connecting rod (1), a connecting clamp (2), a pin (3), and a lower connecting rod (4). The top end of the upper connecting rod (1) is connected to the oil pumping unit, and the bottom end of the lower connecting rod (4) is connected to the oil pump. The upper connecting rod (1), the connecting hoop (2) and the lower connecting rod (4) are all hollow metal rods. The connecting hoop (2) is sleeved on the bottom end of the upper connecting rod (1) and the top end of the lower connecting rod (4), and is fixedly connected to the upper connecting rod (1) and the lower connecting rod (4) by the pin (3).

9. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 8, characterized in that, The pin (3) is an axial limiting pin, and the two ends of the pin (3) are clearance fit with the pin holes of the upper connecting rod (1) and the lower connecting rod (4); The pin (3) is provided with an annular limiting boss in the middle, and the limiting boss and the pin hole sidewall of the lower connecting rod (4) form a ±5° swing gap. The pin (3) is interference-fitted with the pin hole of the upper connecting rod (1). When the lower connecting rod (4) rotates around the pin axis, the limiting boss contacts and limits the pin hole sidewall of the lower connecting rod (4).

10. The intelligent anti-wax and wax-removing integrated sucker rod device according to claim 8, characterized in that, The wax removal system also includes: an oil storage tank (6) and a plug (7); The oil storage tank (6) is screwed to the bottom of the upper connecting rod (1), the plug (7) is screwed onto the bottom of the oil storage tank (6), and the lower end of the plug (7) is connected to the oil pump.

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