Hydraulic blowout preventer state monitoring and alarming method based on flashboard position sensor

Abstract

The invention relates to the technical field of blowout preventers, and discloses a hydraulic blowout preventer state monitoring and alarming method based on a flashboard position sensor. The method comprises the steps that S1, at least one position sensor is installed at a flashboard piston pin shaft of the hydraulic blowout preventer and used for detecting the opening and closing state of a flashboard; s2, collecting a signal of the position sensor, and transmitting the signal to a programmable logic controller (PLC) control system for data processing; and S3, the on-off state of the blowout preventer is judged according to signals of the position sensor. A position sensor is adopted to monitor the gate switch state in real time, a PLC control system is combined for data analysis, and high-precision state judgment is achieved. Different from a traditional scheme which only depends on hydraulic pressure feedback or visual inspection of an operator, the device can comprehensively sense the opening and closing conditions of the flashboard, so that misjudgment or missed judgment caused by visual errors, pressure abnormity or signal lag is avoided, and the safety and reliability of the blowout preventer are improved.

Description

Technical Field

[0001] The invention relates to the technical field of blowout preventers, and in particular to a hydraulic blowout preventer state monitoring and alarm method based on a gate position sensor. Background Art

[0002] Hydraulic blowout preventers are key equipment in well control operations, directly affecting the safety of drilling and downhole operations. In the use of hydraulic blowout preventers, accurately judging the switch status of the gate is the key to ensuring well control safety. However, the existing technology has many defects in this regard, resulting in misjudgment, delayed response and even misoperation. Specifically, the shortcomings of the current technology are mainly reflected in the following aspects.

[0003] Due to the lack of automated monitoring, many drilling and underground operation sites still require manual inspections to confirm the status of the gate. Operators usually rely on visual inspection or mechanical feedback to make judgments, but this method has problems such as strong subjectivity, easy misjudgment due to fatigue, and difficulty in night operations. In addition, manual inspections are usually carried out at regular intervals. If a fault occurs between two inspections, the dangerous situation may not be handled in time, missing the best intervention time.

[0004] Existing BOP monitoring systems often only passively receive status signals, without intelligent analysis and alarm functions. Even if the gate is in an abnormal state, the system usually does not actively remind, but waits until the operator finds the abnormality before taking action. This lag means that many potential safety hazards may not be detected for a long time, and the cause will be traced back when an accident occurs, which is extremely costly.

[0005] At present, the start-up of drilling rigs and well repair equipment is usually independent of the status of the blowout preventer. Operators need to manually confirm the status of the blowout preventer before starting the drilling rig and well repair equipment. However, in a high-pressure operating environment, personnel may start the equipment when the gate is not fully opened due to negligence, misjudgment or operational errors. This problem is particularly prominent in high-intensity operations or emergency situations, and it is very easy to cause equipment damage or even blowout accidents. The lack of an anti-misoperation mechanism makes the safe start-up of drilling and repair equipment overly dependent on manual decision-making, posing a safety hazard that cannot be ignored. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a hydraulic blowout preventer state monitoring and alarm method based on a gate position sensor, which solves the problem that the existing hydraulic blowout preventer relies on manual inspection, resulting in low state monitoring accuracy, delayed response, and high risk of misoperation.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: A hydraulic blowout preventer state monitoring and alarm method based on a gate position sensor comprises the following steps; S1. Install at least one position sensor at the gate piston pin of the hydraulic blowout preventer to detect the switch state of the gate; S2, collecting signals from position sensors and transmitting the signals to a programmable PLC control system for data processing; S3, judging the switch state of the blowout preventer according to the position sensor signal, and dividing the switch state into four states: fully open, half closed, not fully open, and abnormal; S4, when it is detected that the device is not fully opened or in an abnormal state, the alarm module is triggered; S5. Through PLC and drilling and workover equipment control system linkage, lock or operate the workover equipment when the blowout preventer is not fully opened to prevent misoperation.

[0008] Preferably, the signal of the position sensor in step S2 is transmitted to the PLC control system via Modbus, CAN bus or wireless communication.

[0009] Preferably, in step S2, the PLC control system uses signal filtering technology to eliminate unnecessary interference on the signal of the position sensor.

[0010] Preferably, the logic rule for judging the switch status of the blowout preventer in step S3 is as follows: Fully open state: the position sensor detects that the gate is fully retracted; Half-closed state: the position sensor detects that the gate is partially closed; Not fully open: The position sensor does not detect that the gate is fully retracted and has not reached the semi-closed state; Abnormal status: The position sensor signal is abnormal or remains unchanged for a long time.

[0011] Preferably, the alarm module in step S4 includes the following alarm modes: On-site sound and light alarm, set on the driller's console, including red warning light and buzzer; Vibration reminder device on the driller's console or seat; Remote notification device, sends alarm information to the well control command center through wireless communication.

[0012] Preferably, the specific manner of linkage control in step S5 includes: When the BOP is not fully opened, the lifting system of the drilling and repair equipment is locked, and drilling and lowering operations are prohibited; When the BOP is in an abnormal state, pumping operations are prohibited; When the wellhead pressure exceeds the preset threshold and the BOP is not completely closed, the PLC control system automatically triggers the BOP to close the gate.

[0013] Preferably, in step S2, the PLC control system stores all BOP operation data and generates a history log, wherein the log information includes the BOP switch status, alarm events, driller operation records and fault occurrence time.

[0014] Preferably, in step S2, the PLC control system is connected to the SCADA system through a remote monitoring platform to achieve real-time remote monitoring and analysis of the BOP status and has a historical data backtracking function.

[0015] Preferably, the PLC control system in step S2 includes a self-learning module, which can optimize the alarm threshold based on historical data to improve the accuracy of state judgment.

[0016] Preferably, in step S1, the position sensor adopts a magnetic mounting structure and is fixed by an adjustable bracket to adapt to different types of hydraulic blowout preventers. The position sensor includes at least one of a Hall sensor, a magnetoresistive sensor or an inductive sensor.

[0017] The present invention provides a hydraulic blowout preventer state monitoring and alarm method based on a gate position sensor. It has the following beneficial effects: 1. The present invention uses a position sensor to monitor the gate switch status in real time, and combines the PLC control system to perform data analysis to achieve high-precision status judgment. Different from the traditional solution that only relies on hydraulic pressure feedback or operator visual inspection, the present invention can fully perceive the opening and closing of the gate, avoiding misjudgment or missed judgment caused by visual errors, pressure abnormalities or signal lags, and improving the safety and reliability of the blowout preventer.

[0018] 2. Through real-time signal analysis and anomaly detection algorithms, the present invention can automatically trigger sound and light alarms and remote notifications when the gate is not fully opened or abnormal, reminding operators to intervene. Compared with traditional delayed manual inspections, the present invention greatly shortens the response time and reduces the risk of accidents.

[0019] 3. The present invention introduces a linkage strategy between PLC and the control system of the drilling and repair equipment. When the blowout preventer is not fully opened, the operation of the drilling and repair equipment is directly locked to prevent safety hazards caused by misstarting. The existing technology mainly relies on manual confirmation, which has the problems of untimely execution and inaccurate judgment. The present invention avoids this risk from the source.

[0020] 4. By adopting Kalman filtering and self-learning algorithm, the present invention can optimize sensor signals, reduce noise interference, and improve judgment accuracy. Compared with the traditional single threshold judgment method, this technical solution can adaptively adjust the alarm standard according to historical data, reduce false alarms and missed alarms, and ensure the stable operation of the system under complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Please see attached Figure 1 , an embodiment of the present invention provides a hydraulic blowout preventer state monitoring and alarm method based on a gate position sensor, comprising the following steps; S1. Install at least one position sensor at the gate piston pin of the hydraulic blowout preventer to detect the switch state of the gate; Specifically, the main task of step S1 is to ensure that the position sensor can stably and accurately capture the switch state of the gate, thereby providing a reliable data source for subsequent signal acquisition and state judgment. This step is closely connected with other steps in the system, such as signal processing and state judgment, to ensure the stability and reliability of the entire system.

[0024] In this embodiment, at least one position sensor is first installed at the gate piston pin of the hydraulic blowout preventer. The sensor is responsible for real-time monitoring of the position change of the gate and transmitting the signal to the PLC control system for subsequent data processing and status determination. The selection of the position sensor is crucial to the accuracy of the entire system.

[0025] The position sensor can select at least one of the Hall sensor, magnetoresistive sensor or inductive sensor. The installation of the position sensor adopts a magnetic installation structure, which has the advantages of not requiring complex modification and being easy to install. At the same time, the installation position can be adjusted by an adjustable bracket to adapt to different types of hydraulic blowout preventers. The installation position of the sensor needs to be precisely docked with the gate piston pin of the hydraulic blowout preventer to ensure that the gate's switch status can be reflected in real time. The signal transmission method of the position sensor can select standard transmission protocols such as Modbus, CAN bus or wireless communication. These communication methods can ensure that the signal is stably and accurately transmitted to the PLC control system under different working environments. Especially in complex environments, wireless communication provides better flexibility and anti-interference ability, thereby improving the overall reliability of the system.

[0026] The sensor installation method in step S1 plays a vital role in the present invention. By reasonably selecting the sensor type and installation method, it not only ensures the real-time monitoring of the hydraulic blowout preventer status, but also enhances the reliability and safety of the system, providing sufficient technical guarantee for subsequent steps.

[0027] S2, collecting signals from position sensors and transmitting the signals to a programmable PLC control system for data processing; Specifically, step S2 involves the processing and transmission of sensor signals. This step follows the workflow after the sensor is installed, ensuring that the position signal collected by the sensor can be effectively transmitted to the PLC control system and processed through a certain algorithm to provide a reliable basis for subsequent state judgment. The implementation of step S2 is crucial, as it is closely related to subsequent signal judgment, alarm triggering, and linkage control, and directly determines the response speed and accuracy of the system.

[0028] In this embodiment, the signal is transmitted from the position sensor to the PLC control system. The signal output by the sensor is usually a voltage signal, a digital signal or a pulse signal, and its form varies depending on the type of sensor. The PLC control system will pre-process the received signal and provide reliable data support for subsequent state judgment through signal conversion and filtering steps.

[0029] The sensor signal is transmitted in the form of analog signal or digital signal. For analog signal, the PLC system converts it into digital signal through analog-to-digital converter (ADC) to ensure the stability and processability of the signal. For digital signal, PLC directly reads the digital signal and processes it. In this process, the signal transmission path can choose Modbus communication protocol, CAN bus or wireless communication. In practical applications, Modbus and CAN bus have better stability and anti-interference ability, while wireless communication provides better flexibility, especially suitable for complex working environments.

[0030] Specifically, the signal received by the PLC control system is first subjected to noise suppression through low-pass filtering. This filtering process can effectively remove high-frequency interference and maintain the integrity of the signal, especially in industrial environments with severe electromagnetic interference. At this time, the cutoff frequency of the filter should be reasonably configured in combination with the sampling frequency of the signal to prevent the loss of important information.

[0031] Signal processing also includes Kalman filtering, which can estimate the signal in the presence of random noise, thereby improving the system's processing accuracy of sensor data. Kalman filter can estimate parameters through state equations and observation equations: ; ; in: Represents state variables; is the state transition matrix; is the control input matrix; is the control input; is the process noise; is the observed value; is the observation matrix; is the observation noise.

[0032] Specifically, the PLC control system analyzes historical data through the self-learning module, and establishes and updates the optimization model of the alarm threshold in combination with the specific conditions of the equipment operation. The model can automatically adjust the upper and lower limits of the alarm threshold by learning from multiple collected data. For example, when the system runs in a certain state for a long time, after learning from historical data, the alarm threshold can be automatically adjusted to reduce false alarms or missed alarms caused by environmental fluctuations.

[0033] The self-learning module optimizes alarm thresholds by: Based on historical data, the algorithm calculates the range of key parameters of the equipment under normal working conditions, such as the regular switch position of the gate, hydraulic pressure, etc. Based on these regular data, the system automatically sets the preliminary alarm threshold.

[0034] As the equipment runs longer, the PLC system will continue to monitor the equipment status and optimize the alarm threshold based on the comparison between real-time data and historical data to form a dynamic adjustment mechanism.

[0035] When an abnormality occurs, the PLC control system will record the data of the abnormal event and analyze its pattern. If the abnormality occurs in multiple runs, the system will automatically adjust the alarm threshold to adapt to this new operating condition.

[0036] The self-learning module further improves the accuracy of alarm threshold optimization by introducing machine learning algorithms, especially learning methods based on regression analysis or neural networks. Regression analysis can predict future state changes by fitting historical data, while neural networks can make accurate state predictions and threshold adjustments under large data volumes through more complex pattern recognition.

[0037] For example, using the regression model, the following formula can be used to describe the optimization process of the alarm threshold: ; in: is the predicted state of the device; is the historical data input; are the parameters of the model; is the error term.

[0038] By adjusting the parameters The model can more accurately predict the optimal location of the alarm threshold.

[0039] The PLC control system in step S2 can effectively improve the accuracy of state judgment by introducing a self-learning module and optimizing the alarm threshold based on historical data. Through self-learning and data optimization, the system can adapt to different working conditions and environmental changes, reduce false alarms and missed alarms, and improve the intelligence and stability of the system, thereby providing higher reliability for the safety monitoring and state alarm of the hydraulic blowout preventer.

[0040] S3, judging the switch state of the blowout preventer according to the position sensor signal, and dividing the switch state into four states: fully open, half closed, not fully open, and abnormal; Specifically, this step further analyzes the signal transmitted and optimized in step S2 to identify the operating status of the hydraulic blowout preventer, and determines whether to trigger an alarm or perform further safety control measures in combination with the set alarm threshold. This step is a key link in the intelligent monitoring of the system, which directly affects the accuracy of fault identification and the timeliness of response, while ensuring that the system can adapt to different operating environments and maintain stability.

[0041] In this embodiment, the PLC control system first receives the signal optimized in step S2, and performs data analysis according to the preset state model. In general, the system uses a state machine model to classify the gate position. Common states include fully open, half open, fully closed, and abnormal. The key to state judgment lies in how the PLC system matches the real-time data of the sensor with the historical data and makes an accurate state judgment.

[0042] Specifically, the PLC control system comprehensively determines the status of the hydraulic blowout preventer through threshold comparison, trend analysis and anomaly detection technologies: During the threshold comparison process, the system compares the sensor data with the alarm threshold. If the data falls within the set safety range, the device is considered to be in a normal state. If it exceeds the range, further analysis is performed to determine whether an alarm is triggered.

[0043] As an option, the system can also perform trend analysis, that is, judging whether the hydraulic blowout preventer is operating abnormally based on the trend of sensor data changes over a period of time. For example, if the system detects a continuous drop in hydraulic pressure or abnormal fluctuations in gate opening, it can be judged that the equipment may have a leak or mechanical failure.

[0044] In terms of anomaly detection, the PLC system uses an outlier detection algorithm (such as the standard deviation method or Mahalanobis distance) to calculate the degree to which the data deviates from the normal range and determine whether there is an abnormal state. , its standardized deviation can be calculated: ; in: is the historical average; is the historical standard deviation.

[0045] when When the set threshold is exceeded, the system considers the point as abnormal data and further analyzes whether an alarm needs to be triggered.

[0046] Step S3 realizes intelligent judgment of the hydraulic blowout preventer status through in-depth analysis of sensor data, and optimizes the accuracy of status recognition by combining multiple algorithms. At the same time, through the logic decision module, the system can take appropriate countermeasures in abnormal situations to improve safety and reliability. This technical solution ensures the stable operation of the hydraulic blowout preventer under complex working conditions and lays the foundation for subsequent alarm processing and linkage control.

[0047] S4, when it is detected that the device is not fully opened or in an abnormal state, the alarm module is triggered; Specifically, step S4 involves the PLC control system triggering the alarm module when it detects that the gate is not fully opened or is in an abnormal state. This step is based on the state judgment result of step S3, and sends an alarm signal to the operator or remote monitoring system through the alarm module to ensure that timely countermeasures are taken. This step plays a key early warning role in the operation of the entire system, can detect abnormal conditions at an early stage, prevent the fault from further expanding, and improve the safety and reliability of the equipment.

[0048] In this embodiment, after the PLC control system completes the state judgment, if it detects that the gate is not fully opened or is in an abnormal state, the alarm module is immediately activated. Generally, the alarm module includes an audible and visual alarm device, a remote communication interface, and a control linkage mechanism to ensure that the operator can quickly respond to abnormal situations.

[0049] Specifically, the alarm triggering logic of the PLC control system is based on alarm threshold judgment and abnormal signal analysis. The specific triggering conditions include but are not limited to: The gate position signal fed back by the sensor does not reach the set full-open state threshold, and the duration exceeds the set delay time; Combined with the hydraulic pressure, temperature, and load data, a comprehensive judgment was made and abnormal conditions were found; By using the historical data comparison method, it is detected that the deviation between the current state and the normal working state exceeds the set range.

[0050] The PLC system will give priority to triggering local sound and light alarms to ensure that on-site operators can quickly detect abnormal conditions. The sound and light alarm device uses a high-decibel buzzer and a high-brightness LED warning light to maintain high visibility and audibility in a noisy industrial environment. As an option, the system can adjust the alarm intensity according to different alarm levels, such as: In case of slight abnormality, the warning light flashes and the buzzer sounds at a low frequency; In case of serious abnormality, the warning light flashes quickly and the buzzer sounds continuously.

[0051] In a possible implementation, the alarm module also includes a remote alarm function. When the abnormal state continues to be unresolved, the PLC system sends the alarm information to the remote monitoring platform or the operator's mobile terminal. This function can be implemented through Modbus-TCP, MQTT protocol or wireless GSM communication to ensure that remote managers can grasp the equipment status in real time.

[0052] Step S4 triggers the alarm module to achieve a quick response to incomplete opening or abnormal status, ensuring that operators and remote management systems can obtain equipment abnormality information in a timely manner and take corresponding measures. The alarm mechanism combines multiple means such as sound and light alarms, remote alarms and linkage control, which improves the intelligence level and safety of the system and ensures the stable operation of the hydraulic blowout preventer under complex working conditions.

[0053] S5. Through PLC and drilling and repair equipment control system linkage, the drilling and repair equipment operation is locked when the blowout preventer is not fully opened to prevent misoperation; Specifically, step S5 involves the linkage between the PLC control system and the drilling and repair equipment control system to ensure that the drilling and repair equipment operation is locked when the blowout preventer is not fully opened to prevent safety accidents caused by misoperation. This step is based on the alarm judgment result of step S4. When it is detected that the gate is not fully opened or is in an abnormal state, the PLC system automatically sends a locking signal to the drilling and repair equipment control system to limit the start-up or drilling operation of the drilling and repair equipment, thereby avoiding the well control risk caused by the blowout preventer not being in a safe state. The implementation of this step not only improves safety, but also enhances the system's automated control capabilities, allowing the blowout preventer and drilling and repair equipment to work together and reduce the risk of manual intervention.

[0054] In this embodiment, the communication between the PLC control system and the drilling rig control system adopts industrial Ethernet (Ethernet / IP), Modbus-TCP or CAN bus protocol to ensure the real-time and reliability of signal transmission. Generally, when the PLC system determines that the blowout preventer is not fully opened, it will send a locking command to the drilling and repair equipment control system. The command contains information such as the current gate position, hydraulic status, and fault code to ensure that the drilling and repair system can accurately determine the necessity of locking.

[0055] Specifically, the locking logic is based on the following conditions: The gate position reported by the sensor has not reached the fully open state and exceeds the set time threshold; Combined with the hydraulic pressure data, it was found that the blowout preventer failed to reset normally or perform the opening and closing action; When the drilling rig system requested to start drilling operations, the PLC detected that the blowout preventer was still in a partially closed state.

[0056] The PLC control system will first implement a short-term locking strategy, that is, when it detects that the BOP is not fully opened but is still in the normal opening process, the system will temporarily lock the drilling and repair equipment to start, and automatically unlock it after the BOP is completely opened. As an option, when the BOP is in an abnormal state and cannot be reset in a short time, the PLC system will implement a long-term locking strategy and trigger the remote alarm module to notify the operator to intervene manually.

[0057] Step S5 realizes the locking function of the drilling and repair equipment when the blowout preventer is not fully opened through the linkage between the PLC control system and the drilling and repair equipment control system, thereby preventing safety accidents caused by misoperation. The locking strategy combines multiple modes such as short-term locking, long-term locking and warning signals to ensure that the system can respond flexibly under different working conditions.

[0058] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A hydraulic blowout preventer state monitoring and alarm method based on a gate position sensor, characterized in that: The steps include: S1. Install at least one position sensor at the gate piston pin of the hydraulic blowout preventer to detect the switch state of the gate; S2, collecting signals from position sensors and transmitting the signals to a programmable PLC control system for data processing; S3, judging the switch state of the blowout preventer according to the position sensor signal, and dividing the switch state into four states: fully open, half closed, not fully open, and abnormal; S4, when it is detected that the device is not fully opened or in an abnormal state, the alarm module is triggered; S5. Through PLC and drilling and repair equipment control system linkage, the drilling and repair equipment operation is locked when the blowout preventer is not fully opened to prevent misoperation.

2. The hydraulic blowout preventer state monitoring and alarm method based on the gate position sensor according to claim 1 is characterized in that: The signal of the position sensor in step S2 is transmitted to the PLC control system via Modbus, CAN bus or wireless communication.

3. The hydraulic blowout preventer state monitoring and alarm method based on the gate position sensor according to claim 1 is characterized in that: In step S2, the PLC control system uses signal filtering technology to eliminate unnecessary interference on the signal of the position sensor.

4. The hydraulic blowout preventer state monitoring and alarm method based on the gate position sensor according to claim 1 is characterized in that: The logic rule for judging the switch status of the blowout preventer in step S3 is as follows: Fully open state: the position sensor detects that the gate is fully retracted; Half-closed state: the position sensor detects that the gate is partially closed; Not fully open: The position sensor does not detect that the gate is fully retracted and has not reached the semi-closed state; Abnormal status: The position sensor signal is abnormal or remains unchanged for a long time.

5. The hydraulic blowout preventer state monitoring and alarm method based on gate position sensor according to claim 1 is characterized in that: The alarm module in step S4 includes the following alarm modes: On-site sound and light alarm, set on the driller's console, including red warning light and buzzer; Vibration reminder device on the driller's console or seat; Remote notification device, sends alarm information to the well control command center through wireless communication.

6. The hydraulic blowout preventer state monitoring and alarm method based on gate position sensor according to claim 1 is characterized in that: The specific method of linkage control in step S5 includes: When the BOP is not fully opened, the lifting system of the drilling and repair equipment is locked, and drilling and lowering operations are prohibited; When the BOP is in an abnormal state, pumping operations are prohibited; When the wellhead pressure exceeds the preset threshold and the BOP is not completely closed, the PLC control system automatically triggers the BOP to close the gate.

7. The hydraulic blowout preventer state monitoring and alarm method based on gate position sensor according to claim 1 is characterized in that: In step S2, the PLC control system stores all BOP operation data and generates a history log, wherein the log information includes the BOP switch status, alarm events, driller operation records and fault occurrence time.

8. The hydraulic blowout preventer state monitoring and alarm method based on gate position sensor according to claim 1 is characterized in that: In step S2, the PLC control system is connected to the SCADA system through the remote monitoring platform to achieve real-time remote monitoring and analysis of the BOP status and has a historical data backtracking function.

9. The hydraulic blowout preventer state monitoring and alarm method based on gate position sensor according to claim 1 is characterized in that: In step S2, the PLC control system includes a self-learning module, which can optimize the alarm threshold based on historical data and improve the accuracy of state judgment.

10. The hydraulic blowout preventer state monitoring and alarm method based on gate position sensor according to claim 1, characterized in that: In step S1, the position sensor adopts a magnetic mounting structure and is fixed by an adjustable bracket to adapt to different types of hydraulic blowout preventers. The position sensor includes at least one of a Hall sensor, a magnetic resistance sensor or an inductive sensor.

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