Method and system for guaranteeing safety of offshore oil well control equipment

{
  "publication_number": "US11346200B2",
  "country": "US",
  "kind": "B2",
  "title": "Method and system for guaranteeing safety of offshore oil well control equipment",
  "abstract": "The present disclosure belongs to the field of marine engineering, and in particular relates to a method and system for guaranteeing the safety of offshore oil well control equipment. The method comprises: identifying the state of a main structure of the offshore oil well control equipment, identifying the state of a hydraulic control unit of offshore oil well control equipment, identifying the state of an electronic control unit of offshore oil well control equipment, predicting the state of the offshore oil well control equipment and making a real-time decision based on existing information; and the system for guaranteeing the safety of the offshore oil well control equipment comprises a state identification subsystem of a main structure, a state identification subsystem of the hydraulic control unit, a state identification subsystem of the electronic control unit and a state prediction and real-time decision subsystem.",
  "claims": [
    "1. A method for guaranteeing the safety of an offshore oil well control equipment, comprising five major steps: identifying the state of a main structure of the offshore oil well control equipment, identifying the state of a hydraulic control unit of the offshore oil well control equipment, identifying the state of a electronic control unit of the offshore oil well control equipment, predicting the state of the offshore oil well control equipment and making a real-time decision based on existing information; wherein the identifying the state of the main structure of the offshore oil well control equipment specifically comprises: S 101: obtaining states of nodes V 11 V 12... V 1a A 11 A 12... A 1b C 11 C 12... C 1c at a characteristic value acquisition layer of the main structure of the offshore oil well control equipment by signal processing, the corresponding states being V 11 (m 11) V 12 (m 12)... V 1a (m 1a) A 11 (s 11) A 12 (s 12)... A 1b (s 1b) C 11 (w 11) C 12 (w 12)... C 1c (w 1c); S 102: obtaining failure probabilities of corresponding components based on an established Bayesian network, wherein for a component F 1x (x=1,2,... m), a method for solving the fault probabilities is as follows: P ⁡ (F 1 ⁢ x) = ∑ i = 1 n ⁢ ∑ j = 1 y 1 ⁢ i ⁢ P ⁡ (F 1 ⁢ x | I 1 ⁢ i ⁡ (j)) ⁢ P ⁡ (I 1 ⁢ i ⁡ (j) | V 11 ⁡ (m 11) ⁢ ⁢ … ⁢ ⁢ V 1 ⁢ a ⁡ (m 1 ⁢ a), A 11 ⁡ (s 11) ⁢ ⁢ … ⁢ ⁢ A 1 ⁢ ⁢ b ⁡ (s 1 ⁢ b), C 11 ⁡ (w 11) ⁢ ⁢ … ⁢ ⁢ C 1 ⁢ c ⁡ (w 1 ⁢ c)) wherein, P(F 1x |I 1i (j)) represents the component indicated by the x-th node in a state identification layer of the main structure of the offshore oil well control equipment being in a fault state when the i-th node in an intermediate inference layer of the main structure of the offshore oil well control equipment is in a state j; P(I 1i (j)|V 11 (m 11)... V 1a (m 1a),A 11 (s 11)... A 1b (s 1b), C 11 (w 11)... C 1c (w 1c)) represents the probability at which the i-th node in the intermediate inference layer of the main structure of the offshore oil well control equipment is in the j-th state when the nodes V 11 V 12... V 1a A 11 A 12... A 1b C 11 C 12... C 1c in the characteristic value acquisition layer of the main structure of the offshore oil well control equipment are in the states of V 11 (m 11) V 12 (m 12)... V 1a (m 1a) A 11 (s 11) A 12 (s 12)... A 1b (s 1b) C 11 (w 11) C 12 (w 12)... C 1c (w 1c); y 1i represents the number of states possessed by the i-th node in the intermediate inference layer of the main structure of the offshore oil well control equipment; n represents the total number of nodes in the intermediate inference layer of the main structure of the offshore oil well control equipment; and a probability is obtained by existing database through statistics; S 103: judging whether the respective component is in a fault state according to the following rule: (1) the component is considered to be in a fault state when the fault probability is greater than 70%; (2) the component is considered to have a potential fault when the fault probability is between 50% and 70%; (3) the component is considered to be normal when the fault probability is less than 50%; the identifying the state of the hydraulic control unit of the offshore oil well control equipment specifically comprises: S 201: obtaining corresponding states of nodes A 21 A 22... A 2d PT 21 P 22... PT 2e at a characteristic value acquisition layer of the hydraulic control unit of the offshore oil well control equipment by signal processing, the corresponding states being A 21 (s 21) A 22 (s 22)... A 2d (s 2d) P 21 (w 21) PT 22 (w 22)... PT 2e (w 2e); S 202: obtaining fault probabilities of corresponding components based on an established Bayesian network, wherein for a component F 2x (x=1,2,... q), a method for solving the fault probabilities by changing p to q is as follows: P ⁡ (F 2 ⁢ x) = ∑ i = 1 q ⁢ ∑ j = 1 y 2 ⁢ i ⁢ P ⁡ (F 2 ⁢ x | I 2 ⁢ i ⁡ (j)) ⁢ P ⁡ (I 2 ⁢ i ⁡ (j) | A 21 ⁡ (s 21) ⁢ ⁢ … ⁢ ⁢ A 2 ⁢ d ⁡ (s 2 ⁢ d), PT 21 ⁡ (w 21) ⁢ ⁢ … ⁢ ⁢ PT 2 ⁢ e ⁡ (w 2 ⁢ e)) wherein, P(F 2x |I 2i (j)) represents the component indicated by the x-th node in a state identification layer of the hydraulic control unit of the offshore oil well control equipment being in a fault state when the i-th node in an intermediate inference layer of the hydraulic control unit of the offshore oil well control equipment is in a state j; P(I 2i (j)|A 21 (s 21)... A 2d (s 2d), PT 21 (w 21)... PT 2e (w 2e) represents the probability at which the i-th node in the characteristic value acquisition layer of the hydraulic control unit of the offshore oil well control equipment is in the j-th state when the nodes A 21... A 2d PT 21... PT 2e in the characteristic value acquisition layer of the hydraulic control unit of the offshore oil well control equipment are in the states of A 21 (s 21)... A 2d (s 2d) PT 21 (w 21)... PT 2e (w 2e); y 2i represents the number of states possessed by the i-th node in the intermediate inference layer of the hydraulic control unit of the offshore oil well control equipment; q represents the total number of nodes in the intermediate inference layer of the hydraulic control unit of the offshore oil well control equipment; and the conditional probability is obtained by existing database through statistics; S 203: judging whether the respective component is in a fault state according to the following rule: (1) the component is considered to be in a fault state when the fault probability is greater than 70%; (2) the component is considered to have a potential fault when the fault probability is between 50% and 70%; (3) the component is considered to be normal when the fault probability is less than 50%; the identifying the state of the electronic control unit of offshore oil well control equipment specifically comprises: S 301: obtaining corresponding states of control information layers C 31 C 32... C 3f of the electronic control unit of offshore oil well control equipment by signal processing, the corresponding states being C 31 (w 31) C 32 (w 32)... C 3f (w 3f); S 302: obtaining fault probabilities of corresponding components based on an established Bayesian network, wherein for a component F 3x (x=1,2,... r), a method for solving the fault probabilities is as follows: P ⁡ (F 3 ⁢ x) = ∑ i = 1 s ⁢ ∑ j = 1 y 3 ⁢ i ⁢ P ⁡ (F 3 ⁢ x | I 3 ⁢ i ⁡ (j)) ⁢ P ⁡ (I 3 ⁢ i ⁡ (j) | C 3 ⁢ 1 ⁡ (w 3 ⁢ 1), C 3 ⁢ 2 ⁡ (w 3 ⁢ 2) ⁢ ⁢ … ⁢ ⁢ C 3 ⁢ f ⁡ (w 3 ⁢ f)) wherein, P(F 3x |I 3i (j)) represents the component indicated by the x-th node in a state identification layer of the electronic control unit of offshore oil well control equipment being in a fault state when the i-th node in an intermediate inference layer of the electronic control unit of offshore oil well control equipment is in a state j; P(I 3i (j)|C 31 (w 31),C 32 (w 32)... C 3f (w 3f)) represents the probability at which the i-th node in the intermediate inference layer of the electronic control unit of offshore oil well control equipment is in the j-th state when the nodes in the control information layer C 31 C 32... C 3f of the electronic control unit of offshore oil well control equipment are in the states of C 31 (w 31) C 32 (w 32)... C 3f (w 3f); y 3i represents the number of states possessed by the i-th node in the intermediate inference layer of the electronic control unit of offshore oil well control equipment; s represents the total number of nodes in the intermediate inference layer of the electronic control unit of offshore oil well control equipment; and the conditional probability is obtained by the existing database through statistics; S 303: judging whether the respective component is in a fault state according to the following rule: (1) the component is considered to be in a fault state when the fault probability is greater than 70%; (2) the component is considered to have a potential fault when the fault probability is between 50% and 70%; (3) the component is considered to be normal when the fault probability is less than 50%; the predicting the state of the offshore oil well control equipment specifically comprises: S 401: obtaining corresponding states of current state layers F 11 F 12... F 1m F 21 F 22... F 2p F 41 F 32... F 3r of the offshore oil well control equipment by collecting state identification signals, the corresponding states being F 11 (z 41) F 12 (z 42)... F 1m (z 4m) F 21 (u 41) F 22 (u 42)... F 2p (u 4p) F 31 (v 41) F 32 (v 42)... F 3r (v 4r); S 402: obtaining predicted fault probabilities of corresponding components based on an established Bayesian network, wherein for a component P 4x (x=1,2,... t), a method for solving the predicted fault probabilities is as follows: P ⁡ (P 4 ⁢ x) = ∑ i = 1 u ⁢ ∑ j = 1 y 4 ⁢ i ⁢ P ⁡ (P 4 ⁢ x | I 4 ⁢ i ⁡ (j)) ⁢ P ⁡ (I 4 ⁢ i ⁡ (j) | F 1 ⁢ 1 ⁡ (z 4 ⁢ 1), … ⁢ ⁢ F 1 ⁢ m ⁡ (z 4 ⁢ m), F 2 ⁢ 1 ⁡ (u 4 ⁢ 1), … ⁢ ⁢ F 2 ⁢ p ⁡ (u 4 ⁢ p), F 3 ⁢ 1 ⁡ (v 4 ⁢ 1), … ⁢ ⁢ F 3 ⁢ r ⁡ (v 4 ⁢ r)) wherein, P(P 4x |I 4i (j)) represents the probability at which the component indicated by the x-th node in a state prediction layer of the offshore oil well control equipment will have a fault within a future certain time when the i-th node of a state prediction intermediate inference layer of the offshore oil well control equipment is in a state j; P(I 4i (j)|F 11 (z 41),... F 1m (z 4m), F 21 (u 41),... F 2p (u 4p), F 31 (v 41),... F 3r (v 4r) represents the probability at which the i-th node of the state prediction intermediate inference layer of the offshore oil well control equipment is in the j-th state when the nodes F 11 F 12... F 1m F 21 F 22... F 2p F 31 F 32... F 3r in the current state layers of the offshore oil well control equipment are in states of F 11 (z 41) F 12 (z 42)... F 1m (z 4m) F 21 (u 41) F 22 (u 42)... F 2p (u 4p) F 31 (v 41) F 32 (v 42)... F 3r (v 4r); y 4i represents the number of states possessed by the i-th node in the state prediction intermediate inference layer of the offshore oil well control equipment; u represents the total number of nodes in the state prediction intermediate inference layer of the electronic control unit of offshore oil well control equipment; and the conditional probability is obtained by expert decision; S 403: judging whether the respective component will have a fault within 24 hours according to the following rule; (1) the component is considered to have high probability of the fault occurrence within 24 hours when the predicted fault probability is greater than 70%; and (2) the component is considered to have small probability of the fault occurrence within 24 hours when the predicted fault probability is less than 70%; the making a real-time decision based on existing information specifically comprises: S 501: judging whether a fault occurs currently, making panel display and performing shutdown for maintenance if there is the fault, and proceeding to the next step if not; S 502: judging whether there is a predicted fault, allowing the equipment continue to run if there is no predicted fault, and making the panel display and judging whether the predicted fault is a major fault if yes, wherein a method for judging whether the predicted fault is a major fault is as follows: (1) calculating the predicted fault weights by referring to the following formula: ε x =P (P 4x)×γ x wherein, ε x is a corresponding fault weight; P (P 4x) is the predicted fault probability of the x-th component in S 402; γ x is corresponding weight of the x-th component in the system and obtained by expert scoring; (2) considering the predicted fault to be a major fault if the fault weight ε x is greater than 0.4; S 503: performing the shutdown for maintenance if the predicted fault is the major fault, and proceeding to the next step if not; and S 504: repeating S 501 to S 504.",
    "2. A system for guaranteeing the safety of an offshore oil well control equipment implementing the method of claim 1, further comprising a state identification subsystem of a main structure installed on a main structure of the offshore oil well control equipment, a state identification subsystem of a hydraulic control unit installed on the hydraulic control unit of the offshore oil well control equipment, a state identification subsystem of an electronic control unit installed on the electronic control unit of the offshore oil well control equipment and a state prediction and real-time decision subsystem installed in a driller room.",
    "3. A system for guaranteeing the safety of an offshore oil well control equipment, comprising: a state identification subsystem of a main structure installed on a main structure of the offshore oil well control equipment, a state identification subsystem of a hydraulic control unit installed on the hydraulic control unit of the offshore oil well control equipment, a state identification subsystem of an electronic control unit installed on the electronic control unit of the offshore oil well control equipment and a state prediction and real-time decision subsystem installed in a driller room wherein the state identification subsystem of the main structure comprises a vibration sensor group of the main structure, an acoustic emission sensor group of the main structure, a corrosion potentiometer of the main structure, a corrosion signal characteristic value extraction unit of the main structure, an acoustic emission signal characteristic value extraction unit of the main structure, a vibration signal characteristic value extraction unit of the main structure, a state monitoring information fusion unit of the main structure, and a state identification unit of the main structure; the vibration sensor group of the main structure is connected with the main structure of the offshore oil well control equipment by adhesive; the acoustic emission sensor group of the main structure is connected with the main structure of the offshore oil well control equipment by adhesive; the corrosion potentiometer of the main structure is connected with the main structure of the offshore oil well control equipment by adhesive; the corrosion signal characteristic value extraction unit of the main structure is connected with the corrosion potentiometer of the main structure through signal lines; the acoustic emission signal characteristic value extraction unit of the main structure is connected with the acoustic emission sensor group of the main structure through signal lines; the vibration signal characteristic value extraction unit of the main structure is connected with the vibration sensor group of the main structure through signal lines; the state monitoring information fusion unit of the main structure is connected with the corrosion signal characteristic value extraction unit of the main structure, the acoustic emission signal characteristic value extraction unit of the main structure and the vibration signal characteristic value extraction unit of the main structure through signal lines, respectively; and the state identification unit of the main structure is connected with the state monitoring information fusion unit of the main structure through signal lines, wherein the corrosion signal characteristic value extraction unit of the main structure is developed based on DSP; the acoustic emission signal characteristic value extraction unit of the main structure is developed based on the DSP; the vibration signal characteristic value extraction unit of the main structure is developed based on the DSP; the state monitoring information fusion unit of the main structure is developed based on an STM32 data communication module; the state identification unit of the main structure is developed based on the DSP and embedded with a Bayesian algorithm; the signal characteristic value extraction unit of the hydraulic control unit pressure is developed based on the DSP; the signal characteristic value extraction unit of the hydraulic control unit pressure is developed based on the DSP; the state monitoring information fusion unit of hydraulic control unit is developed based on the STM32 data communication module; the state identification unit of the hydraulic control unit is developed based on the DSP and embedded with a Bayesian algorithm; a signal collection unit of the electronic control unit is developed based on the STM32 data communication module; the signal collection unit of the electronic control unit is developed based on the DSP; and the state identification unit of the electronic control unit is developed based on the DSP and embedded with a Bayesian algorithm; the current state collection unit is developed based on a multi-channel signal collection board; the state prediction unit of the offshore oil well control equipment is developed based on DSP and embedded with the Bayesian algorithm; the information fusion unit of the offshore oil well control equipment is developed based on the STM32 data communication module; and the situation-based decision unit is developed based on DSP data processing module.",
    "4. The system for guaranteeing the safety of the offshore oil well control equipment of claim 3, wherein the state identification subsystem of the hydraulic control unit comprises an acoustic emission sensor group of the hydraulic control unit, a pressure signal characteristic value extraction unit of the hydraulic control unit, an acoustic emission signal characteristic value extraction unit of the hydraulic control unit, a state monitoring information fusion unit of the hydraulic control unit, and a state identification unit of the hydraulic control unit; the acoustic emission sensor group of the hydraulic control unit is connected with key valves in the hydraulic control unit of the offshore oil well control equipment by adhesive; the signal characteristic value extraction unit of the hydraulic control unit pressure is connected with pressure sensors in the hydraulic control unit of the offshore oil well control equipment through signal lines; the signal characteristic value extraction unit of the hydraulic control unit pressure is connected with the acoustic emission sensor group of the hydraulic control unit through signal lines; the state monitoring information fusion unit of hydraulic control unit is connected with the signal characteristic value extraction unit of the hydraulic control unit pressure and the signal characteristic value extraction unit of the hydraulic control unit pressure through signal lines, respectively; and the state identification unit of the hydraulic control unit is connected with the state monitoring information fusion unit of hydraulic control unit through signal lines.",
    "5. The system for guaranteeing the safety of the offshore oil well control equipment of claim 3, wherein the state identification subsystem of the electronic control unit comprises a signal collection unit of the electronic control unit, an information screening unit of the electronic control unit, and a state identification unit of the electronic control unit; the signal collection unit of the electronic control unit is connected with interfaces in the electronic control unit of offshore oil well control equipment through signal lines; the information screening unit of the electronic control unit is connected with a signal collection unit of the electronic control unit through signal lines; and the state identification unit of the electronic control unit is connected with the signal collection unit of the electronic control unit through signal lines.",
    "6. The system for guaranteeing the safety of the offshore oil well control equipment of claim 3, wherein the state prediction and real-time decision subsystem comprises a current state collection unit, an information fusion unit of the offshore oil well control equipment, a state prediction unit of the offshore oil well control equipment, a situation-based decision unit, and an online display unit; the current state collection unit is connected with state identification unit of the electronic control unit through signal lines, and is respectively connected with a state identification unit of the hydraulic control unit and a state identification unit of the main structure through waterproof cables; the state prediction unit of the offshore oil well control equipment is connected with the current state collection unit through signal lines; the information fusion unit of the offshore oil well control equipment is connected with the current state collection unit and the state prediction unit of the offshore oil well control equipment through signal lines, respectively; the situation-based decision unit is connected with the information fusion unit of the offshore oil well control equipment through signal lines; and the online display unit is connected with the information fusion unit of the offshore oil well control equipment and the situation-based decision unit through signal lines, respectively.",
    "7. The system for guaranteeing the safety of the offshore oil well control equipment of claim 3, wherein the state identification subsystem of the main structure mainly completes step for identifying the state of the main structure of the offshore oil well control equipment; the state identification subsystem of the hydraulic control unit mainly completes step for identifying the state of the hydraulic control unit of the offshore oil well control equipment; a state identification subsystem of the electronic control unit mainly completes step for identifying the state of electronic control unit of offshore oil well control equipment; and the state prediction and real-time decision subsystem mainly completes step of predicting the state of the offshore oil control equipment and making a real-time decision based on existing information."
  ],
  "description_excerpt": "The present disclosure belongs to the field of marine engineering, and in particular relates to a method and a system for guaranteeing the safety of offshore oil well control equipment.\n\nWith the deepening of a national marine strategy, offshore oil exploitation has become a key issue in the national oil strategy, and the development of the offshore oil equipment has provided technical support for the offshore oil strategy. At the same time, the oil spill in the Gulf of Mexico has sounded the alarm for us and the offshore oil drilling and exploitation accidents will have devastating consequences. Therefore, the exploitation of offshore oil requires highly reliable well control equipment and effective maintenance methods for the well control equipment. Offshore oil well control equipment generally consists of three modules: an electronic control system that processes and sends control commands, a hydraulic control system that provides main control pressure, and a system main body that performs the main tasks. The detection of well control equipment is usually performed by means of regular maintenance, that is, the submarine equipment is regularly hoisted to the drilling platform for testing relevant parameters, and the test parameters are analyzed to assess the state of the well control equipment.\n\nThe traditional maintenance method guarantees the safe operation of offshore oil well control equipment to a certain extent. However, the regular maintenance method fails to monitor the real-time status of the well control equipment, and it is difficult to make a real-time decision on the drilling process.",
  "cpc": [
    "E21B 44/00",
    "E21B 2200/22",
    "G01H 17/00",
    "G01N 27/00",
    "G01N 29/14",
    "G05B 23/0218",
    "G06F 18/24155",
    "G06N 20/00",
    "G06N 5/04",
    "G06N 7/005",
    "G06N 7/01",
    "G06Q 10/0637",
    "G06Q 50/02"
  ],
  "ipc": [
    "E21B 44/00",
    "G06N 5/04",
    "G06N 7/00"
  ],
  "assignees": [
    "China University of Petroleum East China"
  ],
  "inventors": [
    "Baoping CAI",
    "Yonghong Liu",
    "Chao Yang",
    "Xiangdi KONG",
    "Yi Zhao",
    "Hongqi XU",
    "Xincheng Li",
    "Yandong Chen",
    "Renjie JI",
    "Zengkai LIU",
    "Libing Liu",
    "Rikui Zhang",
    "Yuqian YANG",
    "Shitang Liu",
    "Xin Wei"
  ],
  "filing_date": "2019-12-05",
  "publication_date": "2022-05-31",
  "grant_date": "2022-05-31",
  "priority_date": "2019-05-20",
  "application_number": "US-201916704805-A",
  "family_id": "67571302",
  "cited_by_count": 105,
  "citations": [
    "US20120118637A1",
    "US20130124171A1",
    "US20120215450A1",
    "US20120317058A1",
    "CN104899664A"
  ]
}