LNG tanks are complex in design and building process and high in costs,so LNG tank technology is one of the most advanced ones in the field of energy,which has been monopolized by foreign companies for a long time.In ...LNG tanks are complex in design and building process and high in costs,so LNG tank technology is one of the most advanced ones in the field of energy,which has been monopolized by foreign companies for a long time.In order to work out LNG tank technology domestically,China National Offshore Oil Corporation(CNOOC for short),the largest LNG importer in China,develops a LNG tank technology system“CGTank®”successfully in reference to the design and construction experience of domestic and foreign companies,after years of scientific research in tackling difficult problems.This system presents four traits as follows.First,a set of calculation software is developed independently by CNOOC,and the tanks in all operating conditions are calculated after 3D hologram and multi-point contact model of fluid-solid coupling effect is built up.Second,earthquake effect research and inner tank check research are improved innovatively by means of response spectrum analysis after European standards are introduced.Third,it is put forward for the first time that the stress strength discrimination standard is based on the principal stress which is obtained by means of the maximum shearing failure theory.And fourth,a large LNG full-capacity tank technology package with completely independent intellectual property right is established.The“CGTank®”system was first applied in the Tianjin LNG demonstration project,which has passed all indicator tests and is now in operation smoothly.The project is provided with the core tank design technology by CNOOC Gas and Power Group and with the EPC by CNOOC Engineering Co.,Ltd.The independent LNG tank technology can be applied in a wide scope and it is favorable for impelling domestic production of LNG industry completely.展开更多
Offshore oil and gas production has become an important growth pole to ensure national energy security.However,China's offshore oil and gas production is lack of key core technologies and weak in tool and equipmen...Offshore oil and gas production has become an important growth pole to ensure national energy security.However,China's offshore oil and gas production is lack of key core technologies and weak in tool and equipment foundation and can hardly support the optimized fast development of important fields.To solve these technological difficulties,China National Offshore Oil Corporation(CNOOC)insisted on independent technological innovation and overcame a series of key core technologies through theoretical research and key technology research and test during the 13th Five-Year Plan.And the following research results are obtained.First,several key technologies are broken through,including efficient drilling and completion in the middle and deep layers of the Bohai Sea,offshore large-scale heavy oil thermal recovery,deep-water oil and gas field development,and high temperature and high pressure well drilling and completion in the South China Sea,unconventional oil and gas stimulation,and offshore emergency rescue.Domestic first independently operated ultra deep water giant gas field,namely“Deepsea 1”is successfully put into production,so that the leap from 300 m to 1500 m of water depth and from exploration to development is realized.Second,key tools and equipment are developed,such as logging while drilling and rotary steering drilling system,deep-water drilling surface conductor,underwater emergency killing device,and underwater wellhead Christmas tree,which promote the high-quality development of China's offshore oil industry.Finally,some suggestions are proposed as follows.In the future,CNOOC shall strengthen independent technological innovation,quicken the pace to deepsea oil and gas,and continue to research key core technologies for oil and gas reserves and production increase(e.g.continuous localization of drilling and completion technologies,equipment and materials in complex fields),commingled gas production and test and green energy transformation(e.g.geothermal energy),so as to make greater contributions to ensure national energy security and build a maritime power.展开更多
At present,China is facing new strategic opportunities as well as risks and challenges in its development.Faced with the challenges brought by current global major risks,China urgently needs to build a group of world-...At present,China is facing new strategic opportunities as well as risks and challenges in its development.Faced with the challenges brought by current global major risks,China urgently needs to build a group of world-class enterprises as ballast stones.Accelerating the development of a number of world-class enterprises is an important support for China to enhance its comprehensive strength and international competitiveness,and is crucial for the realization of the strategic blueprint for socialist modernization.After more than forty years of reform and opening up,Chinese enterprises have rapidly developed and grown stronger,with their position rising and their influence in the global market increasing continuously.However,Chinese enterprises are“large in size but not yet strong enough”.In this context,this paper systematically analyzes the practical significance and theoretical connotation of building world-class enterprises and the status quo of building world-class enterprises in China and takes CNOOC as an example to deeply analyze the practices of large central enterprises to build world-class enterprises at the levels of group and subsidiaries,providing a reference for Chinese enterprises to accelerate their progress towards world-class enterprises.展开更多
CNOOC is the first“offshore special economic zone”and fully open“industrial sector”in China.2022 witnessed the 40th anniversary of CNOOC.After 40 years,CNOOC has leaped from upstream to downstream,from shallow wat...CNOOC is the first“offshore special economic zone”and fully open“industrial sector”in China.2022 witnessed the 40th anniversary of CNOOC.After 40 years,CNOOC has leaped from upstream to downstream,from shallow water to deep water,and from domestic to international.In the new era of energy transition,CNOOC is set to transform into a world-class green and low-carbon energy product and service provider in an all-round way.展开更多
Depth migration can image complex structures with high accuracy,thereby stimulating the increasingly urgent demands for developing depth-domain inversions and interpretations in industry.The well-seismic calibration i...Depth migration can image complex structures with high accuracy,thereby stimulating the increasingly urgent demands for developing depth-domain inversions and interpretations in industry.The well-seismic calibration in the depth domain serves as a crucial cornerstone for these interpretations and inversions.Well data provide a partial cognition of underground media.Seismic data must be accurately calibrated with well data to expand this cognition outward.Depth-domain seismic data are non-stationary,transforming traditional,mature time-domain well calibration methods unsuitable for direct application to depth-domain seismic data.Therefore,researchers usually adopt a domain transformation strategy to complete well-seismic calibration in the time domain and then convert the calibration results into the depth domain.However,this method inevitably introduces additional error accumulation caused by domain transformation.On the basis of a comprehensive review of previous research,we propose a direct depth-domain well-seismic calibration method.This method is based on the synthesis of the depth-domain seismic records and the extraction of the depth-domain generalized seismic wavelets.We introduce constrained dynamic warping with maximum stretch depth constraint and directly match seismic data with well data in the depth domain.The actual processing results show that the method improves the efficiency of the depth-domain well-seismic calibration and produces a reliable relationship between seismic and well depths after two to four iterations.展开更多
High-precision sand prediction is fundamental to improving the efficiency of oil and gas exploration and development.To address the limitations of traditional fixed-weight fusion strategies,particularly under conditio...High-precision sand prediction is fundamental to improving the efficiency of oil and gas exploration and development.To address the limitations of traditional fixed-weight fusion strategies,particularly under conditions of significant lateral variation in sand body distribution,this study proposesa dynamic weightingdeep neural network(DW-DNN)for adaptive frequency-decomposed attribute fusion.The approach integrates physical constraints with deep learning and introduces two innovations:(i)a priori weight matrices derived from the amplitudefrequency and tuning thickness relationship(amplitude variation with frequency,AvF)are embeddedintothe attention mechanism to adaptivelyallocate multiband seismic attributes,emphasizing high-frequency features for thin sands and low-frequency features for thick sands;and(ii)a deep neural network with a composite loss function combining mean squared error(MSE)and AVF-based constraints is designed to jointly optimize weight allocation and prediction accuracy.The method was applied to the Xi 233 area of theQingcheng Oilfield in the Ordos Basin and compared with conventional approaches.DW-DNN achieved high accuracy and generalizability,with an R2 of 0.92 in the 30%blind-well test,24.3%higher than conventional methods.In addition,91%of well-point errors were within 03 m,while prediction accuracies for thin(≤3 m)and thick(>3 m)sands reached 88%and 91%,respectively.The model also maintained stable performance under low well-control conditions(training-test ratio 5:5).Predicted sand distributions exhibited improved continuity and geologically plausible geometries,clearly delineating channels,lobes,and estuary bars.The results demonstrate that DW-DNN enhances frequency-decomposed attribute fusion through adaptive weight allocation,providing a robust tool for predicting sand body distributions in complex reservoirs.展开更多
基金CNOOC Science and Technology Major Project“Large LNG full-capacity tank design and engineering application”(Grant No.CNOOC-KJ125ZDXM14QD04QD11).
摘要LNG tanks are complex in design and building process and high in costs,so LNG tank technology is one of the most advanced ones in the field of energy,which has been monopolized by foreign companies for a long time.In order to work out LNG tank technology domestically,China National Offshore Oil Corporation(CNOOC for short),the largest LNG importer in China,develops a LNG tank technology system“CGTank®”successfully in reference to the design and construction experience of domestic and foreign companies,after years of scientific research in tackling difficult problems.This system presents four traits as follows.First,a set of calculation software is developed independently by CNOOC,and the tanks in all operating conditions are calculated after 3D hologram and multi-point contact model of fluid-solid coupling effect is built up.Second,earthquake effect research and inner tank check research are improved innovatively by means of response spectrum analysis after European standards are introduced.Third,it is put forward for the first time that the stress strength discrimination standard is based on the principal stress which is obtained by means of the maximum shearing failure theory.And fourth,a large LNG full-capacity tank technology package with completely independent intellectual property right is established.The“CGTank®”system was first applied in the Tianjin LNG demonstration project,which has passed all indicator tests and is now in operation smoothly.The project is provided with the core tank design technology by CNOOC Gas and Power Group and with the EPC by CNOOC Engineering Co.,Ltd.The independent LNG tank technology can be applied in a wide scope and it is favorable for impelling domestic production of LNG industry completely.
基金Project supported by the Science and Technology Project of CNOOC China Limited "Drilling and Completion Risk Evaluation and Countermeasure Study of Ultra High Temperature and High Pressure Development Wel1"(No.YXKY-ZX 09 2021).
摘要Offshore oil and gas production has become an important growth pole to ensure national energy security.However,China's offshore oil and gas production is lack of key core technologies and weak in tool and equipment foundation and can hardly support the optimized fast development of important fields.To solve these technological difficulties,China National Offshore Oil Corporation(CNOOC)insisted on independent technological innovation and overcame a series of key core technologies through theoretical research and key technology research and test during the 13th Five-Year Plan.And the following research results are obtained.First,several key technologies are broken through,including efficient drilling and completion in the middle and deep layers of the Bohai Sea,offshore large-scale heavy oil thermal recovery,deep-water oil and gas field development,and high temperature and high pressure well drilling and completion in the South China Sea,unconventional oil and gas stimulation,and offshore emergency rescue.Domestic first independently operated ultra deep water giant gas field,namely“Deepsea 1”is successfully put into production,so that the leap from 300 m to 1500 m of water depth and from exploration to development is realized.Second,key tools and equipment are developed,such as logging while drilling and rotary steering drilling system,deep-water drilling surface conductor,underwater emergency killing device,and underwater wellhead Christmas tree,which promote the high-quality development of China's offshore oil industry.Finally,some suggestions are proposed as follows.In the future,CNOOC shall strengthen independent technological innovation,quicken the pace to deepsea oil and gas,and continue to research key core technologies for oil and gas reserves and production increase(e.g.continuous localization of drilling and completion technologies,equipment and materials in complex fields),commingled gas production and test and green energy transformation(e.g.geothermal energy),so as to make greater contributions to ensure national energy security and build a maritime power.
摘要At present,China is facing new strategic opportunities as well as risks and challenges in its development.Faced with the challenges brought by current global major risks,China urgently needs to build a group of world-class enterprises as ballast stones.Accelerating the development of a number of world-class enterprises is an important support for China to enhance its comprehensive strength and international competitiveness,and is crucial for the realization of the strategic blueprint for socialist modernization.After more than forty years of reform and opening up,Chinese enterprises have rapidly developed and grown stronger,with their position rising and their influence in the global market increasing continuously.However,Chinese enterprises are“large in size but not yet strong enough”.In this context,this paper systematically analyzes the practical significance and theoretical connotation of building world-class enterprises and the status quo of building world-class enterprises in China and takes CNOOC as an example to deeply analyze the practices of large central enterprises to build world-class enterprises at the levels of group and subsidiaries,providing a reference for Chinese enterprises to accelerate their progress towards world-class enterprises.
摘要CNOOC is the first“offshore special economic zone”and fully open“industrial sector”in China.2022 witnessed the 40th anniversary of CNOOC.After 40 years,CNOOC has leaped from upstream to downstream,from shallow water to deep water,and from domestic to international.In the new era of energy transition,CNOOC is set to transform into a world-class green and low-carbon energy product and service provider in an all-round way.
基金supported by the National Natural Science Foundation of China(No.U23B20158)CNOOC major technology project(KJGG2022-0104)。
摘要Depth migration can image complex structures with high accuracy,thereby stimulating the increasingly urgent demands for developing depth-domain inversions and interpretations in industry.The well-seismic calibration in the depth domain serves as a crucial cornerstone for these interpretations and inversions.Well data provide a partial cognition of underground media.Seismic data must be accurately calibrated with well data to expand this cognition outward.Depth-domain seismic data are non-stationary,transforming traditional,mature time-domain well calibration methods unsuitable for direct application to depth-domain seismic data.Therefore,researchers usually adopt a domain transformation strategy to complete well-seismic calibration in the time domain and then convert the calibration results into the depth domain.However,this method inevitably introduces additional error accumulation caused by domain transformation.On the basis of a comprehensive review of previous research,we propose a direct depth-domain well-seismic calibration method.This method is based on the synthesis of the depth-domain seismic records and the extraction of the depth-domain generalized seismic wavelets.We introduce constrained dynamic warping with maximum stretch depth constraint and directly match seismic data with well data in the depth domain.The actual processing results show that the method improves the efficiency of the depth-domain well-seismic calibration and produces a reliable relationship between seismic and well depths after two to four iterations.
基金funded by the ScienceFoundation of China University of Petroleum(Beijing)(Grant No.2462025BJRC005)Strategic Cooperation Technology Projects of China National Petroleum Corporation(CNPC)and China University of Petroleum(Grant No.ZLZX2020-02)+2 种基金Major Science and Technology Project of Changqing Oilfield(Grant No.2023DZZ04)China University of Petroleum(Grant No.2462023YJRC034)and the National Natural Science Foundation of China(Grant No.42202178,42272110).
摘要High-precision sand prediction is fundamental to improving the efficiency of oil and gas exploration and development.To address the limitations of traditional fixed-weight fusion strategies,particularly under conditions of significant lateral variation in sand body distribution,this study proposesa dynamic weightingdeep neural network(DW-DNN)for adaptive frequency-decomposed attribute fusion.The approach integrates physical constraints with deep learning and introduces two innovations:(i)a priori weight matrices derived from the amplitudefrequency and tuning thickness relationship(amplitude variation with frequency,AvF)are embeddedintothe attention mechanism to adaptivelyallocate multiband seismic attributes,emphasizing high-frequency features for thin sands and low-frequency features for thick sands;and(ii)a deep neural network with a composite loss function combining mean squared error(MSE)and AVF-based constraints is designed to jointly optimize weight allocation and prediction accuracy.The method was applied to the Xi 233 area of theQingcheng Oilfield in the Ordos Basin and compared with conventional approaches.DW-DNN achieved high accuracy and generalizability,with an R2 of 0.92 in the 30%blind-well test,24.3%higher than conventional methods.In addition,91%of well-point errors were within 03 m,while prediction accuracies for thin(≤3 m)and thick(>3 m)sands reached 88%and 91%,respectively.The model also maintained stable performance under low well-control conditions(training-test ratio 5:5).Predicted sand distributions exhibited improved continuity and geologically plausible geometries,clearly delineating channels,lobes,and estuary bars.The results demonstrate that DW-DNN enhances frequency-decomposed attribute fusion through adaptive weight allocation,providing a robust tool for predicting sand body distributions in complex reservoirs.