Integrated well head device for shale gas well trial production and regulation and control method of integrated well head device

Abstract

The invention belongs to the technical field of shale gas well exploitation, and discloses an integrated wellhead device for shale gas well pilot production and a regulation and control method of the integrated wellhead device for shale gas well pilot production. The wellhead safety cut-off unit, the auxiliary production unit, the first-stage throttling pressure reduction unit, the second-stage throttling pressure control unit and the pre-separation metering unit are arranged on the skid-mounted platform and sequentially communicate with one another; a first production parameter detection unit is arranged between the wellhead safety cut-off unit and the auxiliary production unit, a second production parameter detection unit is arranged between the first-stage throttling pressure reduction unit and the second-stage throttling pressure control unit, and a third production parameter detection unit is arranged between the second-stage throttling pressure control unit and the pre-separation metering unit. The wellhead device adapts to the full life cycle of the shale gas well and covers the initial test stage, the long-term gas production stage and the subsequent maintenance and productivity adjustment stage of the gas well, the gas well can obtain adaptive technical support in the whole life cycle, and stable transition and efficient operation of production in all the stages are ensured.

Description

Technical Field

[0001] This invention belongs to the field of shale gas well development technology, and specifically relates to an integrated wellhead device for shale gas well trial production and its control method. Background Technology

[0002] Wellhead equipment typically possesses functions such as throttling and pressure control, flow regulation, and metering. Throttling and pressure control aims to regulate wellhead pressure and ensure safe gas well production. Flow regulation allows for flexible adjustment of gas production rates based on the production capacity requirements of different stages of gas well development. Metering functions are responsible for accurately measuring key data such as the gas and liquid phase flow rates, providing a basis for gas well production assessment and decision-making. With the continuous improvement of shale gas well development capabilities, the demand for economical development of shale gas wells is becoming more urgent, highlighting the growing contradiction between the adaptability of existing wellhead equipment during the testing and production stages.

[0003] Currently, the common practice is to manually replace fixed nozzles with nozzles of different diameters to throttle the flow, and to manually adjust the throttling area of ​​the valve cavity using a needle valve. While this fixed nozzle + needle valve combination design has a certain pressure control and regulation function, the fixed-diameter nozzles require physical replacement to adjust parameters. This discrete nozzle replacement mechanism is difficult to meet the dynamic adjustment needs of the entire trial production process, and each time it requires depressurization, disassembly, installation, and repressurization, which seriously affects the gas well production efficiency. Secondly, high-velocity sand-carrying fluids cause severe erosion of nozzles and pipelines, and improper selection of nozzle size and throttling area can easily induce hydrate blockage or sand deposition. At the same time, existing metering schemes often rely on metering equipment after sand removal and separation, which is complex to maintain, or are limited by the metering accuracy of mixed-phase flow meters, making it difficult to provide real-time feedback of true gas / liquid production data, resulting in a mismatch between pressure control decisions and gas well production status.

[0004] More importantly, existing equipment lacks full life-cycle data perception and intelligent decision-making capabilities. Static throttling parameters cannot respond to the dynamic characteristics of different mining stages, making it difficult to achieve precise matching between wellhead pressure and drainage rate, resulting in premature depletion of formation energy and increased sand production.

[0005] Patent CN116498264A discloses an integrated precision pressure control process for shale gas well pilot production. This process utilizes a multi-stage fixed nozzle throttling mechanism and a parallel production oil circuit design. Based on a pre-programmed system, the opening and closing degrees of the two nozzles in the open circuit are controlled to achieve precise pressure control in shale gas well production. Theoretically, this design can expand the wellhead pressure adjustment range. However, in practice, under typical operating conditions where the wellhead pressure of common shale gas wells is ≤69MPa, a single-stage fixed nozzle throttling mechanism with a reserved straight pipe section of appropriate length can cover more than 90% of the pressure drop requirement. Multi-stage valve groups and parallel circuits result in unnecessary equipment investment and maintenance costs.

[0006] Patent CN111364941A discloses a method and control system for controlling wellhead pressure in shale gas wells. This method adjusts the opening of the nozzle valves accordingly by judging the ratio of pipeline back pressure to wellhead oil pressure and the ratio of the average value to the current critical flow pressure. A remote monitoring system monitors the real-time production status of the gas well and controls the input and modification of model parameters. However, wellhead pressure fluctuates drastically, and threshold control strategies based on pressure ratios are slow to respond to transient wellhead pressure fluctuations. When the pressure fluctuation exceeds the linear adjustment range of the adjustable nozzle, manual intervention is still required to replace the upstream fixed nozzle. Furthermore, when adjusting oilfield development plans, the existing system can only maintain a preset pressure threshold and cannot accurately track production targets through proactive optimization of nozzle size.

[0007] In summary, existing shale gas extraction technologies suffer from several problems, including poor coupling between testing and production stages, low operational efficiency, complex composition of wellhead gas-water mixtures, and fragmented control and metering systems, due to significant differences in operating conditions between the testing and production stages throughout the shale gas well's lifecycle. Furthermore, some technical solutions also suffer from high investment and maintenance costs.

[0008] Therefore, developing a digital wellhead control system with intelligent sensing, dynamic adjustment, and full-cycle adaptability has become a key breakthrough for improving the high-efficiency development of shale gas wells. Summary of the Invention

[0009] To address the above problems, this invention provides an integrated wellhead device and its control method for shale gas well testing and production, employing the following technical solution: An integrated wellhead device for shale gas well testing and production includes a skid-mounted platform, and a wellhead safety cut-off unit, an auxiliary production unit, a primary throttling and pressure reduction unit, a secondary throttling and pressure control unit, and a pre-separation metering unit installed on the skid-mounted platform. The outlet of the wellhead safety cut-off unit is sequentially connected to the auxiliary production unit, the primary throttling and pressure reduction unit, the secondary throttling and pressure control unit, and the pre-separation metering unit. A first production parameter detection unit is provided between the wellhead safety cut-off unit and the auxiliary production unit; a second production parameter detection unit is provided between the first-stage throttling and pressure-reducing unit and the second-stage throttling and pressure-controlling unit; and a third production parameter detection unit is provided between the second-stage throttling and pressure-controlling unit and the pre-separation metering unit.

[0010] Furthermore, it also includes a first valve and a second valve, the first valve being disposed between the auxiliary production unit and the primary throttling and pressure-reducing unit, and the second valve being disposed at the outlet of the pre-separation metering unit.

[0011] Furthermore, the wellhead safety cut-off system is located on one side of the length direction of the skid-mounted platform, and the pre-separation metering unit is located on the other side of the length direction of the skid-mounted platform.

[0012] Furthermore, the primary throttling and depressurization unit is equipped with multiple throttling nozzles of different sizes, the nozzle sizes of which are configured according to the regional gas well platform type, the range of wellhead pressure changes throughout the entire life cycle, and the production volume.

[0013] Furthermore, the pre-separation metering unit includes a pre-separation container, a differential pressure orifice plate flow meter, a multiphase flow meter, an electrically controlled valve, and a shut-off valve; The inlet at the bottom of the pre-separation container is connected to the outlet of the secondary throttling and pressure control unit. The first outlet at the bottom of the pre-separation container is sequentially connected to the multiphase flow meter and the electrically controlled valve. The second outlet at the top of the pre-separation container is sequentially connected to the differential pressure orifice plate flow meter and the shut-off valve. The end of the electrically controlled valve away from the multiphase flow meter is connected to the end of the shut-off valve away from the differential pressure orifice plate flow meter.

[0014] Furthermore, one end of the second valve is connected to the end of the electrically controlled valve that is away from the multiphase flow meter and the end of the shut-off valve that is away from the differential pressure orifice plate flow meter.

[0015] Furthermore, it also includes a control cabinet, which is communicatively connected to the wellhead safety cut-off unit, the secondary throttling and pressure control unit, and the pre-separation metering unit. The control cabinet is also communicatively connected to the field station remote terminal.

[0016] Furthermore, the throttling components inside both the primary throttling and pressure-reducing unit and the secondary throttling and pressure-controlling unit are made of ceramic material.

[0017] The present invention also provides a control method for an integrated wellhead device for shale gas well testing and production, which includes the following steps: The nozzle size of the primary throttling and depressurization unit is determined based on the regional well production dynamics or production needs. After the wellhead safety shut-off unit is opened, the high-temperature, high-pressure, and high-sand-content raw gas flows through the first-stage throttling and pressure-reducing unit, the second-stage throttling and pressure-controlling unit, and the pre-separation and metering unit after being defoamed and antifreeze by the production auxiliary production unit. The gas pressure at the outlet of the secondary throttling and pressure control unit is obtained through the third production parameter detection unit; The gas pressure at the inlet of the first-stage throttling and pressure-reducing unit is obtained through the first production parameter detection unit, and the gas pressure at the outlet of the first-stage throttling and pressure-reducing unit is obtained through the second production parameter detection unit. It is then determined whether the gas pressure drop per unit time passing through the first-stage throttling and pressure-reducing unit is within the adjustment range of the second-stage throttling and pressure-controlling unit. If so, when implementing the pressure drop control production strategy, the pressure and flow rate of the gas are regulated through the secondary throttling pressure control unit, and the third production parameter detection unit is interlocked with the secondary throttling pressure control unit; When implementing the controlled production strategy, determine whether the gas pressure drop per unit time passing through the secondary throttling and pressure control unit is within the set pressure drop range; If so, the gas flow rate is obtained through the pre-separation metering unit, and the pre-separation metering unit is interlocked with the secondary throttling and pressure control unit.

[0018] Furthermore, it also includes the following steps: Pressure and temperature data at different nodes of the wellhead device are obtained through the first production parameter detection unit, the second production parameter detection unit and the third production parameter detection unit. The current production status of the wellhead is determined based on the pressure and temperature data of different nodes of the wellhead device. When the pressure and temperature data of any node exceed the safety threshold, the wellhead safety shut-off unit is controlled to close the wellhead.

[0019] Furthermore, it also includes the following steps: During the testing phase, the wellhead safety shut-off unit is opened, the gas wellhead release rate is regulated by the first-level throttling and depressurization unit, the gas temperature and pressure data for each testing phase are obtained by the second production parameter detection unit, the gas flow rate is obtained by the pre-separation metering unit, and the production strategy model of production, time, pressure and flow rate is obtained based on the gas flow rate, temperature and pressure data, and the production strategy is determined based on the generated strategy model.

[0020] Furthermore, the third production parameter detection unit is interlocked with the secondary throttling and pressure control unit, including the following steps: The secondary throttling and pressure control unit controls the pressure based on real-time production data from the gas well, so that the gas pressure at the outlet of the secondary throttling and pressure control unit approaches the optimal production regime of the gas well. The third production parameter detection unit monitors the gas pressure in real time. If the gas pressure drop is still not within the set pressure drop range and there is no corresponding change trend after the adjustment action of the secondary throttling pressure control unit is completed, the opening of the secondary throttling pressure control unit will be continuously adjusted until the gas pressure drop rate is maintained within the set change range.

[0021] Furthermore, the pre-separation metering unit is interlocked with the secondary throttling and pressure control unit, including the following steps: When the required output is reached, the opening of the secondary throttling and pressure control unit is adjusted according to the gas flow rate monitored in real time by the pre-separation metering unit, so that the gas flow rate at the outlet of the pre-separation metering unit is maintained at the set value.

[0022] The beneficial effects of this invention are: 1. The wellhead device of this invention is adaptable to the entire life cycle of shale gas wells, covering the initial testing stage to the long-term gas production stage, and even the subsequent maintenance and production capacity adjustment stages. The first-stage throttling and pressure reduction unit is a multi-nozzle rotation angle throttling device, and its nozzle size can be flexibly preset according to the wellhead pressure change range and production volume throughout the entire life cycle. The second-stage throttling and pressure control unit meets the requirements for fine pressure control at each stage. The gas well can receive appropriate technical support throughout its entire life cycle, ensuring a smooth transition and efficient operation of production at each stage.

[0023] 2. The wellhead device of this invention has highly efficient integrated functions. It innovatively adopts an integrated skid-mounted structure, which highly integrates various key functional equipment required for the wellhead onto the skid-mounted platform. The equipment is pre-tested and assembled in the factory. After being transported to the site platform, it does not require secondary complex assembly. It can be put into use with only simple connection operations, which greatly simplifies the on-site construction process and avoids the problems of pipe incompatibility caused by the dispersion of components and the large number of interfaces in traditional wellhead construction.

[0024] 3. The pre-separation metering unit of this invention differs from mixed-phase metering methods that are poorly adaptable to complex operating conditions. Based on the differences in gas-liquid flow characteristics, it utilizes vortex separation technology to achieve the gas-liquid pre-separation process. A relatively mature multiphase flow meter, combined with an electronically controlled valve, is used to adjust the fluid flow rate online, controlling the fluid density within a reasonable range. This allows for real-time matching of the dynamic changes in gas and liquid production at each stage, providing a reliable basis for gas well production allocation and yield calculation. Compared to traditional separation metering methods, the pre-separation metering unit of this invention eliminates the need for multiple devices connected in series, significantly saving floor space and avoiding the error accumulation problems caused by numerous devices and complex connections.

[0025] 4. The wellhead device of the present invention has an online production replacement function. The first-stage throttling and pressure reduction unit adopts a unique rotary valve design. When it is necessary to adjust the production strategy, such as changing the nozzle size to adapt to changes in gas well pressure and production volume, there is no need to shut down the gas well and interrupt production. Only the first valve and the second valve are needed. The rotary valve is used to conveniently rotate and switch the nozzle. Then the first valve and the second valve are reopened. The pressure inside the wellhead device remains stable throughout the process. There is no need for pressure relief operation, which greatly reduces the downtime caused by production strategy adjustment, saves a lot of time and energy costs required for pressure relief and pressure restoration, and improves production continuity.

[0026] 5. The wellhead device of this invention constructs a comprehensive, multi-layered data interaction and sharing system. Using the control cabinet as the core hub, it collects and aggregates various production data generated by the wellhead safety shut-off unit, the secondary throttling and pressure control unit, and the pre-separation metering unit in real time, breaking down data barriers between units and enabling free flow and sharing of data within the skid. Simultaneously, the control cabinet seamlessly connects with the remote terminal at the site, ensuring real-time data upload and download, and improving the scientific rigor and timeliness of production decisions.

[0027] 6. The wellhead device control method of the present invention provides two production strategies, including a pressure reduction production strategy and a production allocation strategy. The pressure reduction production strategy achieves refined pressure control throughout the gas well production process, maintaining the wellhead pressure within the ideal range at all times. This effectively avoids a series of production problems caused by pressure runaway, such as freezing and sand blockage, significantly improving the stability and safety of the production process and helping to solidify the foundation for continuous high and stable gas well production. The production allocation strategy, when faced with changes in market demand and the need for specific production volumes, flexibly adjusts the opening of the primary throttling and pressure reduction unit and the secondary throttling and pressure control unit to quickly and accurately allocate gas well production, successfully achieving the desired production allocation, seamlessly connecting with production planning needs, enhancing the adaptability of gas well production to market changes, ensuring that oil and gas resources can be extracted and output according to the optimal plan, and improving the economic benefits of enterprises.

[0028] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description and the drawings. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 A schematic diagram of an integrated wellhead device for shale gas well testing and production according to an embodiment of the present invention is shown. Figure 2 A schematic flowchart of a control method for an integrated wellhead device for shale gas well testing and production according to an embodiment of the present invention is shown.

[0031] In the diagram: 1. Skid-mounted platform; 2. Wellhead safety shut-off unit; 3. Auxiliary production unit; 4. First-stage throttling and pressure reduction unit; 5. Second-stage throttling and pressure control unit; 6. Pre-separation metering unit; 7. Control cabinet; 61. Pre-separation container; 62. Differential pressure orifice plate flow meter; 63. Multiphase flow meter; 64. Electrically controlled valve; 65. Shut-off valve; 81. First valve; 82. Second valve; 91. First production parameter detection unit; 92. Second production parameter detection unit; 93. Third production parameter detection unit. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that the terms "first," "second," etc., used in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," "longitudinal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings.

[0034] This invention provides an integrated wellhead device for shale gas well testing and production. It features a complete set of functions, a simple and centralized structure, and improves the production efficiency of shale gas wells, reduces production costs, and ensures safe and stable production. It also solves problems such as poor coupling between testing and production, low operational efficiency, complex composition of wellhead gas-water mixtures, fragmented control and metering systems, and high investment and maintenance costs caused by the large differences in operating conditions between the testing and production stages throughout the entire life cycle of shale gas wells.

[0035] like Figure 1 As shown, an integrated wellhead device for shale gas well testing and production includes a skid-mounted platform 1, and a wellhead safety cut-off unit 2, an auxiliary production unit 3, a primary throttling and pressure reduction unit 4, a secondary throttling and pressure control unit 5, a pre-separation and metering unit 6, and a control cabinet 7 installed on the skid-mounted platform 1. For example, the controller of the control cabinet 7 can be a PLC.

[0036] The wellhead safety shut-off system is located on one side of the length of the skid-mounted platform 1, the pre-separation metering unit 6 is located on the other side of the length of the skid-mounted platform 1, and the inlet of the wellhead safety shut-off unit 2 is the inlet of the integrated wellhead device. The wellhead raw gas enters from the inlet of the wellhead safety shut-off unit 2.

[0037] The wellhead device of this invention has highly integrated functions and innovatively adopts an integrated skid-mounted structure, which highly integrates various key functional equipment required for the wellhead onto the skid-mounted platform 1. The equipment is pre-tested and assembled in the factory, and after being transported to the site platform, it does not require secondary complex assembly. It can be put into use with only simple connection operations, which greatly simplifies the on-site construction process and avoids the problems of pipe incompatibility caused by the dispersion of components and the large number of interfaces in traditional wellhead construction.

[0038] For example, the safety shut-off unit includes a wellhead safety shut-off valve 65 and matching detection instruments to ensure the safety of platform production; the emergency safety shut-off system has high and low pressure detection and emergency shut-off functions. When the wellhead pressure is abnormal or the temperature changes drastically, it can realize one-click remote rapid well shut-off, quickly realize the well shut-off action, and avoid potential risks in time.

[0039] The outlet of the wellhead safety cut-off unit 2 is connected in sequence to the auxiliary production unit 3, the first-level throttling and pressure reduction unit 4, the second-level throttling and pressure control unit 5, and the pre-separation metering unit 6.

[0040] For example, the auxiliary production unit 3 is equipped with reserved interfaces such as foam discharge agent port and antifreeze injection port. After the high temperature, high pressure and high sand content raw gas is treated by defoaming and antifreeze in the auxiliary production unit 3, it enters the first-level throttling and depressurization unit 4 for depressurization treatment.

[0041] For example, the first-stage throttling and pressure-reducing unit 4 adopts a multi-nozzle rotary throttling device. The first-stage throttling and pressure-reducing unit 4 is equipped with multiple throttling nozzles of different sizes. The nozzle size is configured according to the type of gas well platform in the region, the range of wellhead pressure changes throughout the entire life cycle, and the production volume. During production, according to the gas well production conditions, the rotary mechanism of the first-stage throttling and pressure-reducing unit 4 quickly switches between nozzles of different diameters to perform different levels of pressure reduction treatment online. The production system can be changed without shutting in the well or depressurizing the pipeline, thus controlling the wellhead feed gas pressure within a reasonable range and effectively avoiding problems such as freezing and sand blockage caused by unreasonable or untimely pressure reduction control.

[0042] After being depressurized by the first-stage throttling and depressurization unit 4, the raw gas enters the second-stage throttling and pressure control unit 5. The second-stage throttling and pressure control unit 5 is equipped with a bidirectional high-precision electronic control device, which refines the wellhead throttling pressure control steps and achieves linear adjustment of the pressure within the 1mm equivalent nozzle. This achieves the effect of online supplementary control of the throttling pressure of the upstream first-stage throttling and depressurization unit 4 without shutting down the well, further optimizing the pressure regulation accuracy.

[0043] After being depressurized by the secondary throttling and pressure control unit 5, the raw gas enters the pre-separation and metering unit 6. Inside the pre-separation and metering unit 6, the gas and liquid are initially separated mainly by relying on the vortex separation technology and utilizing the characteristics of each phase fluid in the raw gas.

[0044] For example, the pre-separation metering unit 6 includes a pre-separation container 61, a differential pressure orifice plate flow meter 62, a multiphase flow meter 63, an electrically controlled valve 64, and a shut-off valve 65. The inlet at the bottom of the pre-separation container 61 is connected to the outlet of the secondary throttling and pressure control unit 5. The first outlet at the bottom of the pre-separation container 61 is sequentially connected to the multiphase flow meter 63 and the electrically controlled valve 64. The second outlet at the top of the pre-separation container 61 is sequentially connected to the differential pressure orifice plate flow meter 62 and the shut-off valve 65. The end of the electrically controlled valve 64 that is away from the multiphase flow meter 63 is connected to the end of the shut-off valve 65 that is away from the differential pressure orifice plate flow meter 62.

[0045] The gaseous fluid flows upwards within the pre-separation container 61 due to its own buoyancy, and its flow rate is accurately measured by a differential pressure orifice plate flow meter. If the raw gas contains too much water, the gas phase measurement pipeline shut-off valve 65 is closed, and the flow is measured by the lower pipeline. The mixed-phase fluid that has not yet been completely separated is measured by the multiphase flow meter 63 along the lower pipeline. The multiphase flow meter 63 adopts a venturi tube design, and its variable orifice throat structure automatically and flexibly adjusts according to different gas flow rates. At the same time, the electrically controlled valve 64 adjusts the fluid composition flowing through the multiphase flow meter 63 by changing the fluid flow rate, so that it can accurately match the measurement requirements under different phase states, ensuring the accuracy and efficiency of the entire measurement process in all aspects.

[0046] The pre-separation metering unit 6 of this invention differs from mixed-phase metering methods that are poorly adaptable to complex operating conditions. Based on the differences in gas-liquid flow characteristics, it utilizes vortex separation technology to achieve gas-liquid pre-separation. A relatively mature multiphase flow meter 63, in conjunction with an electrically controlled valve 64, is used to adjust the fluid flow rate online, controlling the fluid density within a reasonable range. This allows for real-time matching of the dynamic changes in gas and liquid production at each stage, providing a reliable basis for gas well production allocation and output calculation. Compared to traditional separation metering methods, the wellhead device of this invention does not require multiple devices connected in series, greatly saving floor space and avoiding the error accumulation problem caused by numerous devices and complex connections.

[0047] For example, the integrated wellhead device also includes a first valve 81 and a second valve 82. The first valve 81 is located between the auxiliary production unit 3 and the first-stage throttling and pressure-reducing unit 4, and the second valve 82 is located at the outlet of the pre-separation metering unit 6. For example, one end of the second valve 82 is connected to the end of the electrically controlled valve 64 that is away from the multiphase flow meter 63 and the end of the shut-off valve 65 that is away from the differential pressure orifice plate flow meter 62.

[0048] For example, the first valve 81 and the second valve 82 can be flat gate valves, which have advantages such as low flow resistance, energy saving and convenient maintenance.

[0049] In this embodiment, valves are configured at the inlet of the primary throttling and pressure-reducing unit 4 and the outlet of the pre-separation metering unit 6 to form a double shut-off, ensuring the safe conduct of equipment maintenance and repair work. Compared with traditional gate valves, which are difficult to open and close under pressure differential, the valve can be easily opened and closed because no pressure relief operation is required when switching production systems in the process, and both sides of the valve are always in an equal pressure state.

[0050] For example, a first production parameter detection unit 91 is provided between the wellhead safety cut-off unit 2 and the auxiliary production unit 3; a second production parameter detection unit 92 is provided between the first-level throttling and pressure-reducing unit 4 and the second-level throttling and pressure-controlling unit 5; and a third production parameter detection unit 93 is provided between the second-level throttling and pressure-controlling unit 5 and the pre-separation metering unit 6.

[0051] In this embodiment of the invention, a first production parameter detection unit 91, a second production parameter detection unit 92, and a third production parameter detection unit 93 are respectively provided for nodes with sudden changes in pressure and temperature. The units are equipped with temperature or pressure transmitters to remotely transmit key data and provide accurate data support for subsequent process control. At the same time, some production parameter detection units are equipped with on-site temperature and pressure gauges so that inspection personnel can check the well conditions at any time and keep abreast of the production dynamics.

[0052] For example, the throttling components inside the primary throttling and pressure-reducing unit 4 and the secondary throttling and pressure-controlling unit 5 are made of erosion-resistant ceramic material; at the same time, through reasonable pressure reduction and flow monitoring, the flow rate and velocity of the raw gas are effectively optimized. This dual technical treatment avoids the risks of wellhead pipelines and equipment failure due to erosion caused by high-pressure, high-speed sand-containing fluids.

[0053] Control cabinet 7 is communicatively connected to wellhead safety cut-off unit 2, secondary throttling and pressure control unit 5, and pre-separation metering unit 6. Control cabinet 7 centrally processes complex data from the wellhead device and issues corresponding control commands. At the same time, control cabinet 7 is also communicatively connected to the field station remote terminal. Data collected by the wellhead device can be transmitted to the field station remote terminal through control cabinet 7, and the wellhead device can be controlled and interlocked for protection through the field station remote terminal.

[0054] This invention utilizes the coordinated operation of an integrated wellhead device (production platform) and a remote terminal unit (RTU) (back-end system) to realize the functions of wellhead safety cut-off, refined control and interlocking of wellhead pressure and flow, and intelligent management and control of skid-mounted equipment in an integrated full life cycle digital wellhead device for shale gas well testing and production.

[0055] The primary throttling and pressure-reducing unit 4 of this invention employs a unique rotary valve design. When production strategies need to be adjusted, such as changing the nozzle size to adapt to changes in gas well pressure and production volume, there is no need to shut down the gas well and interrupt production. Simply close the first valve 81 and the second valve 82, and conveniently rotate the rotary valve to switch the nozzle. Then, reopen the first valve 81 and the second valve 82. Throughout the process, the pressure in the pipeline remains stable, and no pressure relief operation is required. This greatly reduces downtime caused by production strategy adjustments, saves significant time and energy costs required for pressure relief and restoration, and improves production continuity.

[0056] The wellhead device in this embodiment of the invention avoids data silos and constructs a comprehensive, multi-layered data interaction and sharing system. Using control cabinet 7 as the core hub, it collects and aggregates various production data generated by the wellhead safety cutoff unit 2, the secondary throttling and pressure control unit 5, and the pre-separation metering unit 6 in real time, breaking down data barriers between units and enabling free flow and sharing of data within the skid. Simultaneously, control cabinet 7 seamlessly connects with the remote terminal unit (RTU) to ensure real-time data upload and download, improving the scientific rigor and timeliness of production decisions.

[0057] The wellhead device of this invention can be used in different stages of gas well operation, from the initial testing stage to the long-term gas production stage, and even the subsequent maintenance and production adjustment stages. For example, the multi-nozzle rotary angle throttling device of the first-stage throttling and pressure reduction unit 4 can flexibly preset its nozzle size according to factors such as the wellhead pressure variation range and production volume throughout the entire life cycle; the second-stage throttling and pressure control unit 5 introduces a bidirectional high-precision electronic control device to meet the requirements for fine pressure control at each stage. The gas well can receive adaptive technical support throughout its entire life cycle, ensuring a smooth transition and efficient operation of production at each stage.

[0058] Current wellhead production schemes typically separate testing and gas production into two independent phases, lacking continuity and causing production interruptions that fail to meet the demands of efficient and continuous modern oil and gas production. Regarding pressure control, single-stage fixed nozzles are commonly used, failing to provide precise adjustments based on dynamic changes in actual wellhead production conditions, and hindering real-time monitoring and intelligent feedback of the production process. Existing technologies for wellhead feedstock gas metering often employ a method of first desandering and separation on the platform before metering. This method requires numerous large pieces of equipment, consuming significant wellsite space and resulting in high construction costs. Alternatively, multiphase flow meters (63) can be used directly, but due to the complex composition of the wellhead feedstock gas and frequent slug flows, metering results often exhibit significant deviations, failing to provide reliable data support for production decisions.

[0059] This invention also provides a method for the full life-cycle control of shale gas wellheads, based on the aforementioned integrated wellhead device for shale gas well pilot production, which solves the problems in existing wellhead production schemes.

[0060] like Figure 2 As shown, a control method for an integrated wellhead device for shale gas well testing and production includes the following steps: S0, control cabinet 7 opens wellhead safety cut-off unit 2, high temperature, high pressure and high sand content raw gas flows through first-level throttling and pressure reduction unit 4, second-level throttling and pressure control unit 5 and pre-separation metering unit 6 after defoaming and antifreeze treatment in production auxiliary production unit 3.

[0061] S1. Determine the nozzle size of the first-level throttling and pressure-reducing unit 4 based on the regional well production dynamics or production needs.

[0062] S2. Obtain the gas pressure at the outlet of the secondary throttling and pressure control unit 5 through the third production parameter detection unit 93.

[0063] S3. Obtain the gas pressure at the inlet of the first-stage throttling and pressure-reducing unit 4 through the first production parameter detection unit 91, and obtain the gas pressure at the outlet of the first-stage throttling and pressure-reducing unit 4 through the second production parameter detection unit 92. Determine whether the gas pressure drop per unit time passing through the first-stage throttling and pressure-reducing unit 4 is within the adjustment range of the second-stage throttling and pressure-controlling unit 5, for example, the adjustment range is 0 to 3 MPa; if not, redetermine the nozzle size of the first-stage throttling and pressure-reducing unit 4.

[0064] S4. If so, when implementing the pressure reduction production strategy, control cabinet 7 finely regulates the gas pressure and flow rate through the secondary throttling pressure control unit 5, and interlocks the third production parameter detection unit 93 with the secondary throttling pressure control unit 5 P01, as follows: The pressure control production strategy, also known as the precise pressure control mode, involves interlocking the secondary throttling pressure control unit 5 and the third production parameter detection unit 93 in the control cabinet 7 via P01. The secondary throttling pressure control unit 5 serves as the actuator, and the third production parameter detection unit 93 serves as the detection mechanism. Based on the production strategy determined in the previous testing phase, the gas well is subjected to refined pressure control production.

[0065] In this embodiment of the invention, after setting a predetermined pressure system, the pressure of the two-stage throttling and pressure control unit 5 is precisely adjusted to ensure that the daily gas production is above the critical liquid carrying value, while taking into account the wellhead pressure fluctuation. The pressure drop of the gas well per unit time is adjusted, and the impact of the pressure drop of the gas-water mixture in the pipeline on the gas production of the gas well is detected, so as to obtain the optimal strategy for controlling the pressure drop of the gas well.

[0066] For example, a primary throttling and pressure-reducing unit 4 is configured based on the actual formation pressure and regional well production characteristics. This unit controls the gas pressure within a set range, and the size of the throttling element within it is set according to the dynamic production schedule. Simultaneously, a secondary throttling and pressure-controlling unit 5 provides supplementary control of the minute pressure within the 1mm equivalent nozzle.

[0067] The secondary throttling and pressure control unit 5 performs precise pressure control based on real-time production data from the gas well, ensuring that the gas pressure at the outlet of the secondary throttling and pressure control unit 5 approaches the optimal production regime of the gas well. The downstream third production parameter detection unit 93 monitors the gas pressure in real time. If the gas pressure drop is still not within the reasonable pressure drop range and shows no corresponding trend after the secondary throttling and pressure control unit 5 has completed its adjustment, the opening of the secondary throttling and pressure control unit 5 is continuously adjusted until the gas pressure drop rate is maintained within the set range. The secondary throttling and pressure control unit 5 is integrated with the control system to achieve automated operation and support remote monitoring functions.

[0068] S5. When executing the controlled production strategy, determine whether the gas pressure drop per unit time through the secondary throttling and pressure control unit 5 is within the set pressure drop range. If not, the control cabinet 7 adjusts the gas pressure drop amplitude through the secondary throttling and pressure control unit 5.

[0069] S6. If so, the control cabinet 7 obtains the gas flow rate through the pre-separation metering unit 6 and interlocks the pre-separation metering unit 6 with the secondary throttling and pressure control unit 5 P02, as follows: The controlled production strategy, also known as the intelligent production allocation mode, interlocks the secondary throttling and pressure control unit 5 with the pre-separation and metering unit 6 (P02). The secondary throttling and pressure control unit 5 acts as the actuator, and the pre-separation and metering unit 6 acts as the detection mechanism. This achieves the key objective of gas well production control. When a production rate needs to be set, the opening of the secondary throttling and pressure control unit 5 is adjusted based on the gas flow rate monitored in real time by the pre-separation and metering unit 6. This ensures that the gas flow rate at the outlet of the pre-separation and metering unit 6 remains at the set value, thus obtaining the desired production allocation and meeting the production planning requirements.

[0070] This invention provides a refined interlocking control method for pressure or flow based on a two-stage throttling and pressure control unit 5. The two-stage throttling and pressure control unit 5 is interlocked with wellhead pressure or gas well production, and combined with the control cabinet 7, it realizes the core functions of gas well pressure control or production control.

[0071] Upstream of the wellhead assembly, a primary throttling and depressurization unit 4 depressurizes the gas, while downstream, a secondary throttling and pressure control unit 5 precisely regulates the gas pressure. A pre-separation metering unit 6 monitors the gas flow rate, continuously monitoring and transmitting real-time gas flow data. Operators can then gradually adjust the gas well pressure control strategy. By analyzing production variations under different pressure settings, the optimal production control strategy tailored to the gas well's characteristics is determined, ensuring stable and efficient gas well production. This approach meets production planning requirements while avoiding formation pressure imbalances caused by over-exploitation, thus achieving sustainable gas well development.

[0072] In the later gas production stage, the control cabinet 7 regulates the pressure and flow rate at the gas wellhead through the primary throttling and pressure reduction unit 4 and the secondary throttling and pressure control unit 5 to ensure stable downstream pressure and flow rate, while meeting the requirements of the throttling device at different stages. This invention achieves refined control and interlocking of wellhead pressure and flow: the control cabinet 7 interlocks the third production parameter detection unit 93 with the secondary throttling and pressure control unit 5 (P01), or the pre-separation metering unit 6 interlocks the secondary throttling and pressure control unit 5 (P02), thereby controlling the wellhead pressure and flow.

[0073] S7 and control cabinet 7 communicate with the remote terminal unit (RTU). The remote terminal unit obtains the gas flow rate measured by the pre-separation metering unit 6, as well as the gas pressure and temperature before and after passing through the first-stage throttling and pressure reduction unit 4 and the second-stage throttling and pressure control unit 5 through the control cabinet 7.

[0074] For example, a control method for an integrated wellhead device for shale gas well testing and production according to an embodiment of the present invention further includes the following steps: S8. Wellhead Safety Cut-off: Control cabinet 7 obtains pressure and temperature data of different nodes of the wellhead device through the first production parameter detection unit 91, the second production parameter detection unit 92 and the third production parameter detection unit 93. Based on the pressure and temperature data of different nodes of the wellhead device, the current production status of the wellhead is determined. When the pressure and temperature data of any node exceeds the safety threshold, the wellhead safety cut-off unit 2 is controlled to close the wellhead.

[0075] The wellhead production status includes: pressure exceeding the upper limit of the safety value after throttling and pressure control, pressure within the safe range after throttling and pressure control, wellhead temperature fluctuating within a reasonable range, and abnormal wellhead pressure fluctuation.

[0076] S9. In the early testing phase, the optimal production output of the gas well is matched: In the early testing phase, the wellhead safety shut-off unit 2 is opened slowly and gradually, and the gas wellhead release rate is finely controlled through the first-level throttling and depressurization unit 4. The gas temperature and pressure data under each testing phase are obtained through the second production parameter detection unit 92, and the gas flow rate is obtained through the pre-separation metering unit 6. Based on the gas flow rate, temperature and pressure data, a production strategy model of production output, time, pressure and flow rate is obtained, and the production strategy is determined based on the generated strategy model.

[0077] For example, the nozzle opening of the first-stage throttling and pressure-reducing unit 4 is set in a small range (such as 4-6mm) to prevent sudden pressure drops from causing sand production in the formation and to maintain wellbore stability.

[0078] Subsequently, flow rate tests were conducted by progressively increasing the nozzle size of the first-level throttling and pressure-reducing unit 4. Starting with smaller nozzle sizes, the tests were switched sequentially to larger sizes, and flow rate and pressure data were recorded at each test stage. The gas well production capacity was then quantitatively evaluated step by step in a detailed manner.

[0079] The second production parameter detection unit 92 monitors and collects temperature and pressure data during the operation of the wellhead equipment. The first-level throttling and depressurization unit 4 controls the pressure drop rate of the wellhead gas-water mixture within the set range. Taking advantage of the sufficient formation energy, the fracturing fluid is returned to the maximum extent while controlling formation sand production.

[0080] After completing the step-by-step testing, the first-level throttling and pressure-reducing unit 4 uses the largest-sized nozzle to conduct extended flow testing to further explore the gas well's potential. Based on the temperature and pressure data collected by the second production parameter detection unit 92, a production strategy model for production, time, pressure, and flow is obtained. The production strategy is determined according to the generated strategy model, laying the foundation for accurate judgment of gas well production status, optimization of production plans, and long-term production prediction of gas wells.

[0081] Data from the early testing phase of shale gas wells provides a basis for subsequent stable production control strategies. This invention, through testing gas well drainage parameters under different drainage strategies during the early testing phase, helps to find the optimal production method and improve recovery rate and economic benefits.

[0082] The wellhead device control method of the present invention provides two production strategies, including a pressure reduction production strategy and a production allocation strategy. Among them, the pressure reduction production strategy realizes precise pressure control operation throughout the gas well production process, keeping the wellhead pressure within the ideal range at all times. This effectively avoids a series of production problems caused by pressure runaway, such as freezing and sand blockage, and greatly improves the stability and safety of the production process, helping to lay a solid foundation for continuous high and stable gas well production.

[0083] The production control and allocation strategy allows for flexible adjustment of the opening degree of the primary throttling and pressure reduction unit 4 and the secondary throttling and pressure control unit 5 when faced with changes in market demand and the need for specific output. This enables rapid and precise allocation of gas well output, successfully achieving the desired production allocation, seamlessly connecting with production planning needs, enhancing the adaptability of gas well production to market changes, ensuring that oil and gas resources can be extracted and output according to the optimal plan, and improving the economic benefits of the enterprise.

[0084] S10. Smart Management of Skid-Mounted Equipment: Control cabinet 7 acquires pressure and temperature data through the first production parameter detection unit 91, the second production parameter detection unit 92, and the third production parameter detection unit 93, and acquires flow data through the pre-separation metering unit 6. Based on the acquired pressure, temperature, and flow data, it issues execution commands to control the wellhead safety cut-off unit 2 and the secondary throttling and pressure control unit 5, and uploads the pressure, temperature, and flow data to the field station remote terminal. Through the high-efficiency oil and gas production module and expert-assisted diagnostic system configured in the field station remote terminal, execution instructions are generated to ensure smart management of wellhead production.

[0085] In the complex and unpredictable process of shale gas extraction, the testing and gas extraction equipment on the shale gas extraction platform inevitably encounters various abnormal conditions or even malfunctions due to the interplay of geological conditions, equipment operating time, and various unforeseen factors, such as wellhead overpressure, abnormal temperature fluctuations, oil nozzle sand blockage, valve puncture and leakage, and other thorny problems.

[0086] S11. The gas well production process is handled for abnormal situations and faults through the wellhead safety cut-off unit 2, the first valve 81 and the second valve 82.

[0087] S111 Emergency Response to Wellhead Overpressure and Abnormal Temperature Fluctuations: When the wellhead pressure suddenly spikes above the safety threshold or the temperature fluctuates violently and irregularly, the system can quickly respond by cutting off the connection between the wellhead and the external pipeline through the one-click shut-off function of the wellhead safety shut-off unit 2, thereby timely curbing the high-pressure and high-temperature airflow and ensuring the safety of personnel, equipment and the surrounding environment.

[0088] S112. Strategy for handling sand blockage in primary throttling and pressure reduction unit 4 under extreme sand conditions: Under certain extremely harsh geological conditions, the sand content in the gas well feed gas may far exceed expectations. If the nozzle size of the sand blockage in primary throttling and pressure reduction unit 4 is relatively small, when the gas flow carries a large amount of sand particles through at high speed, it is very easy for sand particles to accumulate and block at the nozzle of primary throttling and pressure reduction unit 4. Primary throttling and pressure reduction unit 4 can be cleaned by closing the first valve 81 and the second valve 82.

[0089] S113. Incomplete fracturing and plugging operations leading to leakage in the secondary throttling and pressure control unit 5: If the initial fracturing and plugging operations are not thorough enough, residual underground metal material may enter the wellhead equipment with the gas flow. If the nozzle size of the upstream primary throttling and pressure reduction unit 4 is improperly set, resulting in uneven gas flow velocity and pressure distribution, the high-speed impacting gas flow carrying metal particles can easily cause wear on the sealing parts or valve core of the secondary throttling and pressure control unit 5, leading to leakage.

[0090] Upon detecting a leak in the secondary throttling and pressure control unit 5, operators can quickly close the first valve 81 and the second valve 82 to prevent more impurities from entering the wellhead equipment and avoid further deterioration of the fault. Simultaneously, the primary throttling and pressure-reducing unit 4 should be cleaned, and the leaking secondary throttling and pressure control unit 5 should be promptly repaired or replaced to fully restore the system's normal operation and ensure the continuity of gas well production operations.

[0091] Through the targeted response strategies for the three typical failure scenarios described above, the wellhead device control method of this invention provides strong technical support for shale gas platforms when facing complex and ever-changing working conditions, ensuring the safety, stability, and efficiency of gas well extraction, and safeguarding the sustainable development of shale gas wells.

[0092] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An integrated wellhead device for shale gas well testing and production, characterized in that, It includes a skid-mounted platform (1), and a wellhead safety cut-off unit (2), an auxiliary production unit (3), a first-stage throttling and pressure-reducing unit (4), a second-stage throttling and pressure-controlling unit (5), and a pre-separation metering unit (6) installed on the skid-mounted platform (1); The outlet of the wellhead safety cut-off unit (2) is connected in sequence to the auxiliary production unit (3), the first-level throttling and pressure reduction unit (4), the second-level throttling and pressure control unit (5), and the pre-separation metering unit (6); A first production parameter detection unit (91) is provided between the wellhead safety cut-off unit (2) and the auxiliary production unit (3), a second production parameter detection unit (92) is provided between the first-level throttling and pressure-reducing unit (4) and the second-level throttling and pressure-controlling unit (5), and a third production parameter detection unit (93) is provided between the second-level throttling and pressure-controlling unit (5) and the pre-separation metering unit (6).

2. The integrated wellhead device for shale gas well testing and production according to claim 1, characterized in that, It also includes a first valve (81) and a second valve (82), the first valve (81) being disposed between the auxiliary production unit (3) and the first-stage throttling and pressure-reducing unit (4), and the second valve (82) being disposed at the outlet of the pre-separation metering unit (6).

3. The integrated wellhead device for shale gas well testing and production according to claim 1, characterized in that, The wellhead safety cut-off system is located on one side of the length direction of the skid-mounted platform (1), and the pre-separation metering unit (6) is located on the other side of the length direction of the skid-mounted platform (1).

4. The integrated wellhead device for shale gas well testing and production according to claim 1, characterized in that, The primary throttling and pressure reduction unit (4) is equipped with multiple throttling nozzles of different sizes. The nozzle size is configured according to the regional gas well platform type, the range of wellhead pressure changes throughout the entire life cycle, and the production volume.

5. The integrated wellhead device for shale gas well testing and production according to claim 2, characterized in that, The pre-separation metering unit (6) includes a pre-separation container (61), a differential pressure orifice plate flow meter (62), a multiphase flow meter (63), an electrically controlled valve (64), and a shut-off valve (65); The inlet at the bottom of the pre-separation container (61) is connected to the outlet of the secondary throttling and pressure control unit (5). The first outlet at the bottom of the pre-separation container (61) is connected in sequence to the multiphase flow meter (63) and the electrically controlled valve (64). The second outlet at the top of the pre-separation container (61) is connected in sequence to the differential pressure orifice plate flow meter (62) and the shut-off valve (65). The end of the electrically controlled valve (64) away from the multiphase flow meter (63) is connected to the end of the shut-off valve (65) away from the differential pressure orifice plate flow meter (62).

6. The integrated wellhead device for shale gas well testing and production according to claim 5, characterized in that, One end of the second valve (82) is connected to the end of the solenoid valve (64) away from the multiphase flow meter (63) and the end of the shut-off valve (65) away from the differential pressure orifice flow meter (62).

7. The integrated wellhead device for shale gas well testing and production according to any one of claims 1-6, characterized in that, It also includes a control cabinet (7), which is communicatively connected to the wellhead safety cut-off unit (2), the secondary throttling and pressure control unit (5), and the pre-separation metering unit (6). The control cabinet (7) is also communicatively connected to the field station remote terminal.

8. The integrated wellhead device for shale gas well testing and production according to claim 1, characterized in that, The throttling components inside the primary throttling and pressure reduction unit (4) and the secondary throttling and pressure control unit (5) are all made of ceramic.

9. A control method for an integrated wellhead device for shale gas well testing and production, characterized in that, The integrated wellhead device for shale gas well testing and production as described in any one of claims 1-8 includes the following steps: Based on the regional well production dynamics or production needs, determine the nozzle size of the primary throttling and depressurization unit (4); After the wellhead safety shut-off unit (2) is opened, the high-temperature, high-pressure, and high-sand-content raw gas flows through the first-level throttling and pressure-reducing unit (4), the second-level throttling and pressure-controlling unit (5), and the pre-separation and metering unit (6) after the defoaming and antifreeze treatment of the production auxiliary production unit (3). The gas pressure at the outlet of the secondary throttling and pressure control unit (5) is obtained through the third production parameter detection unit (93); The gas pressure at the inlet of the first-stage throttling and pressure-reducing unit (4) is obtained by the first production parameter detection unit (91), and the gas pressure at the outlet of the first-stage throttling and pressure-reducing unit (4) is obtained by the second production parameter detection unit (92). It is then determined whether the gas pressure drop through the first-stage throttling and pressure-reducing unit (4) per unit time is within the adjustment range of the second-stage throttling and pressure-controlling unit (5). If so, when implementing the pressure reduction production strategy, the pressure and flow rate of the gas are regulated by the secondary throttling pressure control unit (5), and the third production parameter detection unit (93) is interlocked with the secondary throttling pressure control unit (5); When implementing the controlled production strategy, it is determined whether the gas pressure drop per unit time passing through the secondary throttling and pressure control unit (5) is within the set pressure drop range; If so, the gas flow rate is obtained through the pre-separation metering unit (6), and the pre-separation metering unit (6) is interlocked with the secondary throttling and pressure control unit (5).

10. The control method for the integrated wellhead device for shale gas well testing and production according to claim 9, characterized in that, It also includes the following steps: Pressure and temperature data at different nodes of the wellhead device are obtained through the first production parameter detection unit (91), the second production parameter detection unit (92), and the third production parameter detection unit (93); The current production status of the wellhead is determined based on the pressure and temperature data of different nodes of the wellhead device. When the pressure and temperature data of any node exceed the safety threshold, the wellhead safety cut-off unit (2) is controlled to close the wellhead.

11. The control method for the integrated wellhead device for shale gas well testing and production according to claim 9, characterized in that, It also includes the following steps: During the testing phase, the wellhead safety shut-off unit (2) is opened, the gas wellhead release rate is controlled by the first-level throttling and depressurization unit (4), the gas temperature and pressure data under each testing phase are obtained by the second production parameter detection unit (92), the gas flow rate is obtained by the pre-separation metering unit (6), and the production strategy model of production, time, pressure and flow rate is obtained based on the gas flow rate, temperature and pressure data. The production strategy is determined based on the generated strategy model.

12. The control method for an integrated wellhead device for shale gas well testing and production according to any one of claims 9-11, characterized in that, Interlocking the third production parameter detection unit (93) with the secondary throttling pressure control unit (5) includes the following steps: The secondary throttling and pressure control unit (5) performs pressure control based on the real-time production data of the gas well, so that the gas pressure at the outlet of the secondary throttling and pressure control unit (5) approaches the optimal production system of the gas well. The third production parameter detection unit (93) monitors the gas pressure in real time. If the gas pressure drop is still not in the set pressure drop range and there is no corresponding change trend after the adjustment action of the secondary throttling pressure control unit (5), the opening degree of the secondary throttling pressure control unit (5) will be continuously adjusted until the gas pressure drop rate is maintained in the set change range.

13. The control method for an integrated wellhead device for shale gas well testing and production according to any one of claims 9-11, characterized in that, Interlocking the pre-separation metering unit (6) with the secondary throttling pressure control unit (5) includes the following steps: When the required output is reached, the opening of the secondary throttling and pressure control unit (5) is adjusted according to the gas flow rate monitored in real time by the pre-separation metering unit (6) so that the gas flow rate at the outlet of the pre-separation metering unit (6) remains at the set value.

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