Intelligent control system of blowout preventer

Abstract

The invention relates to the technical field of drilling equipment, in particular to an intelligent control system for a blowout preventer, which comprises a monitoring module for monitoring pressure data of a plurality of monitoring positions near a wellhead, well fluid return quantity, real-time drilling depth, position information of a sliding sleeve in a single opening and closing process and running current data of a driving motor; the calculation module and the control module are used for determining a pressure fluctuation state according to the pressure data, the real-time drilling depth and a dynamic pressure threshold value, determining an overflow fluctuation state according to the well liquid return amount so as to determine a jet state, determining a treatment mode of a blowout preventer, and determining the displacement of a sliding sleeve according to the position information; determining the running state of the motor according to the running current data, and judging whether the blowout preventer breaks down or not according to the comparison result of the displacement of the sliding sleeve and the preset displacement or the running state of the motor; the execution module executes opening and closing actions on the ball valve according to the processing mode; the early warning module sends out an alarm signal according to the fault judgment result; intelligent control over the blowout preventer is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of drilling equipment, and in particular to an intelligent control system for a blowout preventer. Background Art

[0002] Blowout preventers are safety sealing wellhead devices commonly used in oil fields to prevent blowouts. They are used to close the wellhead during operations such as oil testing, well repair, and well completion to prevent blowout accidents, maintain wellbore pressure balance, and provide a safe and reliable working environment for wellhead operations.

[0003] Traditional top drive internal blowout preventers are divided into upper blowout preventers and lower blowout preventers. They need to be replaced frequently during long-term operation, which is prone to damage and failure of the upper blowout preventer or the lower blowout preventer, which can easily affect the progress of drilling operations and increase operating costs. When the blowout preventer is damaged and fails, the risk of blowout will increase significantly during the period before replacement. Blowouts may cause secondary disasters such as fires and explosions, posing a serious threat to the lives of personnel on the drilling platform and causing huge pollution to the surrounding environment.

[0004] Therefore, there is an urgent need for an intelligent control system for BOPs to monitor the working status of the BOPs in real time and issue early warnings in a timely manner to ensure that workers can take appropriate measures before the BOPs fail completely, such as adjusting drilling parameters, preparing replacement parts in advance, etc., to reduce the risks caused by BOP failure. Summary of the invention

[0005] To this end, the present invention provides a blowout preventer intelligent control system to overcome the problem of insufficient monitoring capability of blowout preventer failure damage in the prior art.

[0006] To achieve the above object, the present invention provides a blowout preventer intelligent control system, comprising:

[0007] A monitoring module, which is used to monitor the pressure data of several monitoring positions near the wellhead at several monitoring time points, the return volume of well fluid at the wellhead and the real-time drilling depth of the drilling tool during the drilling process, and is also used to monitor the position information of the sliding sleeve of the blowout preventer during a single opening and closing process and the operating current data of the drive motor;

[0008] a calculation module connected to the monitoring module, for determining a pressure fluctuation state according to the pressure data, the real-time drilling depth and a dynamic pressure threshold, determining an overflow fluctuation state according to the well fluid return amount, and determining an injection state according to the pressure fluctuation state and the overflow fluctuation state;

[0009] a control module connected to the calculation module, for determining a processing method for the blowout preventer according to the injection state, determining a sleeve displacement according to the position information, determining a motor operation state according to the operating current data, and determining whether the blowout preventer fails according to a comparison result between the sleeve displacement and a preset displacement or the motor operation state;

[0010] an execution module, which is connected to the control module and includes a drive motor, a hydraulic pump, a cylinder, a sleeve and left and right knobs, and is used to control the drive motor, the hydraulic pump, the cylinder, the sleeve and the left and right knobs according to the processing method so that the ball valve performs an opening and closing action;

[0011] An early warning module, which is connected to the control module and sends out an alarm signal according to the fault judgment result;

[0012] The pressure fluctuation state is a consistent fluctuation or a differential fluctuation, the overflow fluctuation state includes a stable fluctuation and a sharp fluctuation, and the injection state is a true injection state or a false injection state.

[0013] Furthermore, the control module determines a corresponding pressure variation amplitude according to the pressure data at a single monitoring position, and determines the pressure fluctuation state according to the pressure variation amplitude and a dynamic pressure threshold.

[0014] Furthermore, the control module constructs a dynamic model of formation pressure according to historical drilling depths and historical pressure data, and determines the dynamic pressure threshold according to the dynamic model of formation pressure and real-time drilling depth.

[0015] Furthermore, the control module determines the pressure fluctuation state according to the number of positions where the pressure change amplitude exceeds the dynamic pressure threshold and the total number of monitoring positions, wherein:

[0016] If the difference between the number of positions and the total number of monitoring positions is less than or equal to a first threshold, the pressure fluctuation state is a consistent fluctuation;

[0017] If the difference between the number of positions and the total number of monitored positions is greater than a first threshold, the pressure fluctuation state is a differential fluctuation.

[0018] Furthermore, the control module determines a well fluid return rate according to the well fluid return amount, and determines an overflow fluctuation state according to a comparison result between the well fluid return rate and a preset return rate, wherein:

[0019] If the well fluid return rate is less than the preset return rate, the overflow fluctuation state is a stable fluctuation;

[0020] If the well fluid return rate is greater than or equal to the preset return rate, the overflow fluctuation state is a sharp fluctuation.

[0021] Further, the control module determines the injection state, wherein:

[0022] If the pressure fluctuation state is a consistent fluctuation, and the overflow fluctuation state is a sharp fluctuation, the injection state is a true injection state;

[0023] If the pressure fluctuation state is a differential fluctuation, and the overflow fluctuation state is a stable fluctuation, the injection state is a false injection state.

[0024] Furthermore, the control module determines a treatment method for the blowout preventer, wherein:

[0025] If the injection state is a true injection state, the driving motor drives the ball valve in the blowout preventer to close automatically at a preset speed;

[0026] If the injection state is a false injection state, the ball valve in the blowout preventer is continuously opened.

[0027] Furthermore, the control module determines whether the blowout preventer fails according to the displacement of the sleeve and the preset displacement, wherein:

[0028] If the displacement of the sliding sleeve is less than the preset displacement, the blowout preventer fails.

[0029] Furthermore, the control module determines the current stabilization starting point according to the operating current data in a single switching process, and determines the motor operation state according to the operating current change rate after the current stabilization starting point and a preset dynamic change rate.

[0030] Furthermore, the control module determines the motor operation state based on the comparison result between the running current change rate and the preset dynamic change rate, wherein:

[0031] If the running current change rate is lower than the preset dynamic change rate, the motor running state is a stable running state;

[0032] If the running current change rate is greater than or equal to the preset dynamic change rate, the motor operation state is an abnormal fluctuation state.

[0033] Compared with the prior art, the beneficial effect of the present invention is that the present invention determines the wellhead injection state according to the pressure data of several monitoring positions near the wellhead at several monitoring time points during the drilling process, the return amount of well fluid at the wellhead, and the real-time drilling depth of the drilling tool, accurately distinguishes between true and false injections, avoids the mistaken closure of the blowout preventer during false injections, and causes shutdowns and inspections, and improves the overall operation efficiency. At the same time, accurate fault diagnosis is performed based on the position information of the sliding sleeve and the operating current data of the drive motor during the single opening and closing process of the blowout preventer, and the fault point is quickly located, further improving the safety of the drilling operation, ensuring the sustainable advancement of the drilling operation, and realizing intelligent control of the blowout preventer.

[0034] Furthermore, the present invention determines the corresponding pressure change amplitude according to the pressure data at a single monitoring position, and determines the pressure fluctuation state according to the pressure change amplitude and the dynamic pressure threshold, so as to facilitate further accurate distinction between true and false blowouts, avoid mistaken shutdown of the blowout preventer during false blowouts, and cause shutdowns and inspections, thereby improving overall operating efficiency. The safety of drilling operations is further improved, the sustainable advancement of drilling operations is ensured, and intelligent control of the blowout preventer is achieved.

[0035] Furthermore, the present invention determines the well fluid return rate according to the well fluid return volume, determines the overflow fluctuation state according to the comparison result between the well fluid return rate and the preset return rate, and further accurately distinguishes true blowout from false blowout in combination with the pressure fluctuation state, avoids the mistaken closure of the blowout preventer during false blowout, resulting in shutdown and investigation, and improves the overall operation efficiency. It further improves the safety of drilling operations, ensures the sustainable advancement of drilling operations, and realizes intelligent control of the blowout preventer.

[0036] Furthermore, the present invention determines the operating status of the sleeve and the motor during the opening and closing of the ball valve according to the comparison between the displacement of the sleeve and the preset displacement, and the operating current data during a single opening and closing process, and further performs fault judgment, manually closes the blowout preventer, and improves the overall operation efficiency. It further improves the safety of drilling operations, ensures that drilling operations can be continuously advanced, and realizes intelligent control of the blowout preventer. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of the blowout preventer structure in which the blowout preventer intelligent system is applied in an embodiment of the present invention;

[0038] Figure 2 for Figure 1 Schematic diagram of the structural cross section of the middle valve body;

[0039] Figure 3 It is a connection block diagram of the blowout preventer intelligent control system according to an embodiment of the present invention;

[0040] Figure 4 A decision diagram for determining the injection state in an embodiment of the present invention;

[0041] In the figure: 1, valve body; 11, upper valve seat; 12, lower valve seat; 13, wave spring; 14, ball valve; 15, left and right knobs; 16, O-ring; 17, elastic retaining ring; 2, oil cylinder; 3, slide plate; 4, slider; 5, roller; 6, sleeve; 7, knob wrench. DETAILED DESCRIPTION

[0042] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0043] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0044] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0045] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] See also Figure 1 , Figure 2 As shown, Figure 1 Schematic diagram of the blowout preventer structure using the blowout preventer intelligent system according to an embodiment of the present invention. The blowout preventer can be controlled in two ways: automatic control and manual control. The blowout preventer includes: a valve body 1, a cylinder 2, a slide plate 3, a slider 4, a roller 5, a sleeve 6, and a knob wrench 7. Figure 2 for Figure 1 The schematic diagram of the structure cross section of the middle valve body 1, the valve body 1 comprises an upper valve seat 11 and a lower valve seat 12, the wave spring 13 is installed on the upper valve seat 11, the outer surface of the valve body 1 is symmetrically provided with holes for installing left and right knobs 15, and the inside is sealed with an O-ring 16, wherein the switch state of the internal ball valve 14 is controlled by the left and right knobs 15, and the driving motor is driven to rotate under the control of the automated program system to drive the hydraulic pump to move the oil cylinder 2 up and down, the oil cylinder 2 drives the sliding sleeve 6 to move up and down, and the hexagon inside the plug drives the left and right knobs 15 of the blowout preventer to switch the blowout preventer.

[0047] Figure 3 The figure is a connection block diagram of an intelligent control system for a blowout preventer according to an embodiment of the present invention. Specifically, the present invention provides an intelligent control system for a blowout preventer, including:

[0048] A monitoring module, which is used to monitor the pressure data of several monitoring positions near the wellhead at several monitoring time points, the return amount of well fluid at the wellhead and the real-time drilling depth of the drilling tool during the drilling process, and is also used to monitor the position information of the sliding sleeve 6 and the operating current data of the drive motor during a single opening and closing process of the blowout preventer;

[0049] a calculation module connected to the monitoring module, for determining a pressure fluctuation state according to the pressure data, the real-time drilling depth and a dynamic pressure threshold, determining an overflow fluctuation state according to the well fluid return amount, and determining an injection state according to the pressure fluctuation state and the overflow fluctuation state;

[0050] a control module connected to the calculation module, for determining a processing method for the blowout preventer according to the injection state, determining a sleeve displacement according to the position information, determining a motor operation state according to the operating current data, and determining whether the blowout preventer fails according to a comparison result between the sleeve displacement and a preset displacement or the motor operation state;

[0051] an execution module, which is connected to the control module and includes a drive motor, a hydraulic pump, a cylinder, a sleeve and left and right knobs, and is used to control the drive motor, the hydraulic pump, the cylinder, the sleeve and the left and right knobs according to the processing method so that the ball valve performs an opening and closing action;

[0052] An early warning module, which is connected to the control module and sends out an alarm signal according to the fault judgment result;

[0053] The pressure fluctuation state is a consistent fluctuation or a differential fluctuation, the overflow fluctuation state includes a stable fluctuation and a sharp fluctuation, and the injection state is a true injection state or a false injection state.

[0054] It is understandable that during drilling operations, blowouts are extremely dangerous accidents that may cause catastrophic consequences such as casualties, environmental pollution, and equipment damage. Therefore, the blowout preventer intelligent monitoring system is used for all-round monitoring to detect the risk of blowouts at the first time, automatically control the action of the blowout preventer, and reduce the probability of blowouts. Blowouts include true blowouts and false blowouts. True blowouts refer to the imbalance of formation pressure in the well, and the formation fluid (such as oil, natural gas, formation water, etc.) breaks through the pressure barrier of the drilling fluid under the strong pressure, and rapidly gushes from the bottom of the well along the wellbore to the wellhead. False blowouts are usually caused by non-formation pressure out-of-control factors such as equipment failure, abnormal drilling parameters, or external interference.

[0055] When similar blowout phenomena occur, they should be distinguished to avoid accidents. For example, if a false blowout is treated as a real blowout, the blowout preventer will be frequently opened and closed, delaying the construction period and accelerating the wear of the mechanical parts and seals of the blowout preventer, shortening the service life of the equipment. On the contrary, if a real blowout is treated as a false blowout, and no effective well sealing measures are taken after the blowout occurs, the formation fluid will flow out of the wellhead uncontrollably in large quantities, bringing about an instant high-pressure shock, which can easily lead to the collapse of the drilling platform, casualties, and economic losses.

[0056] It is understandable that by monitoring the pressure data near the wellhead, the return volume of the well fluid and the real-time drilling depth of the drilling tool, it is possible to determine whether the injection state is a true injection state or a false injection state, and at the same time, corresponding processing is performed according to the injection state control system, including opening and closing the blowout preventer. Furthermore, since the opening and closing of the ball valve 14 is affected by the motor drive and the movement of the sleeve 6, the position information of the sleeve 6 and the operating current data of the drive motor are monitored during a single opening and closing process to help better determine the fault state of the blowout preventer, and the blowout preventer can be manually closed by the staff in time to prevent further losses.

[0057] In a specific embodiment, the monitoring module includes a pressure sensor for monitoring the pressure data of several monitoring positions near the wellhead at several monitoring time points during the drilling process, a flow sensor for monitoring the return amount of well fluid from the wellhead, a depth sensor for monitoring the real-time drilling depth of the drilling tool, a displacement sensor for monitoring the position information of the sliding sleeve 6 of the blowout preventer during a single opening and closing process, and a current sensor for monitoring the operating current data of the drive motor. Several monitoring positions can be pressure sensors set at a distance of 20 cm in the same well cross section 0.5 m below the wellhead; the time interval of the several monitoring time points ranges from 1 min to 3 min, preferably, the time interval of the several monitoring time points is 2 min; in implementation, the value range and preferred value of the time interval of the several monitoring positions and the several monitoring time points can be determined according to actual conditions, and are not specifically limited here and will not be repeated.

[0058] In another specific embodiment, in addition to judging the fault based on the displacement of the sleeve and the motor operating status of the drive motor, multiple parameters such as the pressure of the hydraulic pump and the working status of each sensor in the monitoring module can also be monitored to establish a comprehensive fault diagnosis model, conduct a comprehensive analysis of these parameters, and improve the accuracy and reliability of fault judgment.

[0059] The present invention determines the wellhead jetting state according to the pressure data of several monitoring positions near the wellhead at several monitoring time points during the drilling process, the return amount of well fluid at the wellhead, and the real-time drilling depth of the drilling tool, accurately distinguishes between true and false jetting, avoids the accidental closure of the blowout preventer during false jetting, and causes shutdown and investigation, and improves the overall operation efficiency. At the same time, accurate fault diagnosis is performed according to the position information of the sliding sleeve 6 and the operating current data of the driving motor during the single opening and closing process of the blowout preventer, and the fault point is quickly located, further improving the safety of the drilling operation, ensuring the sustainable advancement of the drilling operation, and realizing the intelligent control of the blowout preventer.

[0060] See also Figure 4 As shown, it is a judgment diagram for determining the injection state in an embodiment of the present invention. Specifically, the control module determines the corresponding pressure change amplitude according to the pressure data at a single monitoring position, and determines the pressure fluctuation state according to the pressure change amplitude and the dynamic pressure threshold.

[0061] Specifically, the control module constructs a formation pressure dynamic model according to historical drilling depths and historical pressure data, and determines the dynamic pressure threshold according to the formation pressure dynamic model and real-time drilling depth.

[0062] It is understandable that when a real blowout occurs, the pressure imbalance in the underground formation is the root cause, and the pressure will rise rapidly and continue to rise. However, when a false blowout occurs, the pressure change amplitude is small, and the fluctuation is irregular and differentiated. Therefore, the wellhead pressure data is monitored at several monitoring time points to determine the wellhead pressure fluctuation state, so as to facilitate the subsequent accurate judgment of the injection state. The dynamic pressure threshold is a reference value for measuring the pressure change amplitude, which is used to determine whether the pressure change amplitude at adjacent monitoring time points reaches the real blowout state.

[0063] In a specific embodiment, at a single monitoring position, the pressure change amplitude is the pressure data difference at adjacent detection time points. The control module constructs a formation pressure dynamic model based on historical drilling depth and historical pressure data. More complex algorithms such as polynomial regression and neural network can be used for fitting to describe the relationship between pressure and depth as accurately as possible to construct a formation pressure dynamic model. The model can reflect the general law of formation pressure changes with depth in the drilling area, while taking into account the influence of local special formations; the dynamic pressure threshold is determined according to the formation pressure dynamic model and the real-time drilling depth. The real-time drilling depth is substituted into the formation pressure dynamic model to determine the estimated wellhead pressure value. The dynamic pressure threshold value ranges from 5% to 15% of the estimated wellhead pressure value. Preferably, the dynamic pressure threshold value is 10% of the estimated wellhead pressure value.

[0064] Specifically, the control module determines the pressure fluctuation state according to the number of positions where the pressure change amplitude exceeds the dynamic pressure threshold and the total number of monitoring positions, wherein:

[0065] If the difference between the number of positions and the total number of monitoring positions is less than or equal to a first threshold, the pressure fluctuation state is a consistent fluctuation;

[0066] If the difference between the number of positions and the total number of monitored positions is greater than a first threshold, the pressure fluctuation state is a differential fluctuation.

[0067] It can be understood that the total number of monitoring positions is the total number of several monitoring positions. In the true spray state, the pressure fluctuation amplitude is large, and the pressure fluctuation amplitudes of each monitoring position are approximately the same, while in the false spray state, the pressure fluctuation amplitude is small, and there may be a slight leakage of the seal that affects the nearby pressure, resulting in differential fluctuations in the pressure fluctuation amplitudes of each monitoring position. Therefore, the pressure fluctuation state is judged to further determine whether the injection state is true or false.

[0068] In a specific embodiment, the value range of the first threshold is 0 to 2. Preferably, the value of the first threshold is 0. When the number of positions where the pressure change amplitude exceeds the dynamic pressure threshold is consistent with the total number of monitoring positions, it means that the pressure fluctuation amplitudes of each monitoring position are approximately consistent, and the pressure fluctuation state is a consistent fluctuation.

[0069] The present invention determines the corresponding pressure change amplitude according to the pressure data at a single monitoring position, and determines the pressure fluctuation state according to the pressure change amplitude and the dynamic pressure threshold, so as to facilitate further accurate distinction between true and false blowouts, avoid mistaken shutdown of the blowout preventer during false blowouts, and cause shutdown and investigation, thereby improving overall operation efficiency. The safety of drilling operations is further improved, the sustainable advancement of drilling operations is ensured, and intelligent control of the blowout preventer is realized.

[0070] Specifically, the control module determines the well fluid return rate according to the well fluid return amount, and determines the overflow fluctuation state according to the comparison result between the well fluid return rate and the preset return rate, wherein:

[0071] If the well fluid return rate is less than the preset return rate, the overflow fluctuation state is a stable fluctuation;

[0072] If the well fluid return rate is greater than or equal to the preset return rate, the overflow fluctuation state is a sharp fluctuation.

[0073] It can be understood that the well fluid return rate is the ratio of the well fluid return volume at a single monitoring time point to the theoretical well fluid return volume. If the well fluid return rate is greater than or equal to the preset return rate, it means that a large amount of well fluid is returned from the wellhead. This may be because the fluid in the formation, under the strong pressure, flows into the wellbore in large quantities and quickly returns to the wellhead, which is a sharp fluctuation. If the well fluid return rate is less than the preset return rate, it means that the pressure change at the wellhead is not obvious. This may be because there is no large amount of high-pressure fluid flowing into the wellbore, or even if some fluid enters, its energy is not enough to cause a significant change in the wellhead pressure, which is defined as a stable fluctuation.

[0074] In a specific embodiment, the well fluid return rate is the ratio of the difference in well fluid return amounts at adjacent monitoring time points to the well fluid return amount at the previous monitoring time point between the two monitoring time points. The value range of the preset return rate is ±1% to ±20%. Preferably, the value of the preset return rate is ±15%. In implementation, the value range and preferred value of the preset return rate can be determined according to actual conditions, and no specific limitation is made here and will not be repeated.

[0075] Specifically, the control module determines the injection state, wherein:

[0076] If the pressure fluctuation state is a consistent fluctuation, and the overflow fluctuation state is a sharp fluctuation, the injection state is a true injection state;

[0077] If the pressure fluctuation state is a differential fluctuation, and the overflow fluctuation state is a stable fluctuation, the injection state is a false injection state.

[0078] It can be understood that if the return volume of well fluid increases sharply at the same time, the return rate rises, and the pressure fluctuations near the wellhead tend to be consistent, it is judged to be a true blowout state. If the pressure fluctuations are small, the return volume of well fluid is basically stable or has only slight changes, it is judged to be a false blowout state.

[0079] Specifically, the control module determines the processing method for the blowout preventer, wherein:

[0080] If the injection state is a true injection state, the driving motor drives the ball valve 14 in the blowout preventer to close automatically at a preset speed;

[0081] If the injection state is a false injection state, the ball valve 14 in the blowout preventer is continuously opened.

[0082] It is understandable that the control module can respond quickly at the moment of detecting signs of real blowout (such as a sharp rise in wellhead pressure, a surge in well fluid return, etc.), start the motor and hydraulic pump and other components, control the motor to rotate to drive the hydraulic pump and cylinder to move, the cylinder drives the sliding sleeve 6 to move, and the hexagon inside the plug drives the blowout preventer knob to rotate to close the ball valve 14 and the blowout preventer. If a false blowout is detected, the blowout preventer ball valve 14 can be kept open and continuous monitoring can be continued.

[0083] The present invention determines the well fluid return rate according to the well fluid return volume, determines the overflow fluctuation state according to the comparison result between the well fluid return rate and the preset return rate, and further accurately distinguishes true blowout from false blowout in combination with the pressure fluctuation state, avoids the mistaken closure of the blowout preventer during false blowout, resulting in shutdown and investigation, and improves the overall operation efficiency. It further improves the safety of drilling operations, ensures the sustainable advancement of drilling operations, and realizes intelligent control of the blowout preventer.

[0084] Specifically, the control module determines whether the blowout preventer fails according to the displacement of the sleeve and the preset displacement, wherein:

[0085] If the displacement of the sliding sleeve is less than the preset displacement, the blowout preventer fails.

[0086] In a specific embodiment, the hydraulic pump is driven by the rotation of the motor, and the hydraulic pump drives the cylinder sleeve 6 to move up and down. During the process from opening to closing of the ball valve 14, the sleeve 6 will move up and down. Therefore, the preset displacement is defined as the moving distance from the starting position to the end of the sleeve 6 during the process from opening to closing of the ball valve 14. If the sleeve displacement is less than the preset displacement, it means that in the series of mechanical transmission processes from the motor to the hydraulic pump, and then from the hydraulic pump to the cylinder sleeve 6, there are problems such as excessive friction between transmission components, loose connection parts, or damaged components, which causes power loss during the transmission process, affecting the normal moving distance of the sleeve 6 and preventing it from reaching the preset value. At this time, an early warning signal can be issued through the early warning module, and the staff manually closes the blowout preventer to avoid related losses.

[0087] Specifically, the control module determines the current stabilization starting point according to the operating current data in a single switching process, and determines the motor operation state according to the operating current change rate after the current stabilization starting point and a preset dynamic change rate.

[0088] Specifically, the control module determines the motor operation state based on the comparison result between the running current change rate and the preset dynamic change rate, wherein:

[0089] If the running current change rate is lower than the preset dynamic change rate, the motor running state is a stable running state; if the running current change rate is greater than or equal to the preset dynamic change rate, the motor running state is an abnormal fluctuation state, and the control module determines that the blowout preventer is faulty when the motor running state is an abnormal fluctuation state.

[0090] It is understandable that when the motor starts normally and drives the hydraulic pump to operate, the operating current of the motor will quickly rise to a stable value. The time point when the motor rises to a stable current is defined as the current stabilization starting point. After determining the current stabilization starting point, focus on the change of the operating current after the starting point. The operating state of the motor is determined by calculating the operating current change rate and comparing it with the preset dynamic change rate. If the operating current change rate is lower than the preset dynamic change rate, it means that the operation of the drive motor is relatively stable, and the motor operation state is determined to be a stable operating state. On the contrary, if the operating current change rate is greater than or equal to the preset dynamic change rate, it means that the blowout preventer is likely to fail, because the unstable and abnormal fluctuations in the operation of the motor often reflect problems in the power transmission, mechanical coordination or electrical control of the entire system, and these problems may affect the normal control of the ball valve 14 by the blowout preventer, thereby affecting its blowout prevention function. At this time, an early warning signal can be issued through the early warning module, and the staff can manually close the blowout preventer to avoid related losses.

[0091] In a specific embodiment, the operating current change rate is the ratio of the difference in operating current data at adjacent time points after the current stabilization starting point to the operating current data at the previous time point during a single switching process. The preset dynamic change rate has a value range of ±5% to ±10%. Preferably, the preset dynamic change rate has a value of ±8%. In implementation, the value of the preset dynamic change rate can be determined based on actual conditions. No specific limitation is made here and no further details are given.

[0092] In another specific embodiment, in addition to judging the fault based on the displacement of the sleeve and the operating current of the drive motor, parameters such as the hydraulic pressure of the hydraulic pump and the working status of each sensor can also be monitored. By combining multiple parameters to establish a fault diagnosis model, these parameters are comprehensively analyzed to improve the accuracy and reliability of fault judgment. In implementation, the method of judging the blowout preventer fault can be determined according to the actual situation, which is not specifically limited here and will not be repeated.

[0093] The present invention determines the operating state of the sleeve 6 and the motor during the opening and closing of the ball valve 14 according to the comparison between the displacement of the sleeve and the preset displacement, and the operating current data during a single opening and closing process, and further performs fault judgment, manually closes the blowout preventer, and improves the overall operation efficiency. The safety of drilling operations is further improved, the sustainable advancement of drilling operations is ensured, and intelligent control of the blowout preventer is achieved.

[0094] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A blowout preventer intelligent control system, characterized in that: include: A monitoring module, which is used to monitor the pressure data of several monitoring positions near the wellhead at several monitoring time points, the return volume of well fluid at the wellhead and the real-time drilling depth of the drilling tool during the drilling process, and is also used to monitor the position information of the sliding sleeve in the blowout preventer and the operating current data of the drive motor during a single opening and closing process; a calculation module connected to the monitoring module, for determining a pressure fluctuation state according to the pressure data, the real-time drilling depth and a dynamic pressure threshold, determining an overflow fluctuation state according to the well fluid return amount, and determining an injection state according to the pressure fluctuation state and the overflow fluctuation state; a control module connected to the calculation module, for determining a processing method for the blowout preventer according to the injection state, determining a sleeve displacement according to the position information, determining a motor operation state according to the operating current data, and determining whether the blowout preventer fails according to a comparison result between the sleeve displacement and a preset displacement or the motor operation state; an execution module, which is connected to the control module and includes a drive motor, a hydraulic pump, a cylinder, a sleeve and left and right knobs, and is used to control the drive motor, the hydraulic pump, the cylinder, the sleeve and the left and right knobs according to the processing method so that the ball valve performs an opening and closing action; An early warning module, which is connected to the control module and sends out an alarm signal according to the fault judgment result; The pressure fluctuation state is a consistent fluctuation or a differential fluctuation, the overflow fluctuation state includes a stable fluctuation and a sharp fluctuation, and the injection state is a true injection state or a false injection state.

2. The BOP intelligent control system according to claim 1, characterized in that: The control module determines the corresponding pressure change amplitude according to the pressure data at a single monitoring position, and determines the pressure fluctuation state according to the pressure change amplitude and a dynamic pressure threshold.

3. The BOP intelligent control system according to claim 2 is characterized in that: The control module constructs a formation pressure dynamic model according to historical drilling depths and historical pressure data, and determines the dynamic pressure threshold according to the formation pressure dynamic model and real-time drilling depth.

4. The BOP intelligent control system according to claim 2, characterized in that: The control module determines the pressure fluctuation state according to the number of positions where the pressure change amplitude exceeds the dynamic pressure threshold and the total number of monitoring positions, wherein: If the difference between the number of positions and the total number of monitoring positions is less than or equal to a first threshold, the pressure fluctuation state is a consistent fluctuation; If the difference between the number of positions and the total number of monitored positions is greater than a first threshold, the pressure fluctuation state is a differential fluctuation.

5. The BOP intelligent control system according to claim 2, characterized in that: The control module determines the well fluid return rate according to the well fluid return amount, and determines the overflow fluctuation state according to the comparison result between the well fluid return rate and the preset return rate, wherein: If the well fluid return rate is less than the preset return rate, the overflow fluctuation state is a stable fluctuation; If the well fluid return rate is greater than or equal to the preset return rate, the overflow fluctuation state is a sharp fluctuation.

6. The BOP intelligent control system according to claim 5, characterized in that: The control module determines an injection state, wherein: If the pressure fluctuation state is a consistent fluctuation, and the overflow fluctuation state is a sharp fluctuation, the injection state is a true injection state; If the pressure fluctuation state is a differential fluctuation, and the overflow fluctuation state is a stable fluctuation, the injection state is a false injection state.

7. The intelligent control system for blowout preventer according to claim 6, characterized in that: The control module determines the treatment method for the blowout preventer, wherein: If the injection state is a true injection state, the driving motor drives the ball valve in the blowout preventer to close automatically at a preset speed; If the injection state is a false injection state, the ball valve in the blowout preventer is continuously opened.

8. The BOP intelligent control system according to claim 1, characterized in that: The control module determines whether the blowout preventer fails according to the displacement of the sleeve and the preset displacement, wherein: If the displacement of the sliding sleeve is less than the preset displacement, the blowout preventer fails.

9. The BOP intelligent control system according to claim 1, characterized in that: The control module determines the current stabilization starting point according to the operating current data in a single switching process, and determines the motor operation state according to the operating current change rate after the current stabilization starting point and a preset dynamic change rate.

10. The intelligent control system for blowout preventer according to claim 9, characterized in that: The control module determines the motor operation state based on the comparison result between the running current change rate and the preset dynamic change rate, wherein: If the running current change rate is lower than the preset dynamic change rate, the motor running state is a stable running state; If the running current change rate is greater than or equal to the preset dynamic change rate, the motor operation state is an abnormal fluctuation state.

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