The objective of this paper is to investigate and discuss the increased capability of technology in detecting archaeological sites in a submerged environment. The paper will discuss the dynamic methods using dynamic sonars and magnetometers and how these data are analyzed and interpreted. Advances in sonar technology have allowed for more advanced archaeological analytical capabilities. New sub-bottom profiling techniques and analytical capabilities are broadening the resolution in which discreet objects and features can be defined in the sub-surface. Advances in magnetometer processing has also allowed for an advancement in the capability for detecting small magnetic anomalies at depth and creating larger comprehensive profiles of near-surface archaeological materials. Utilizing new processing techniques in conjunction with these technologies opens the door to interpretive methods that can aid archaeologists in identifying potential archaeological sites and can help refine the process of protecting or researching these sites. The ongoing work of imaging the near-surface Pleistocene boundary within the North American continental shelf has allowed for higher resolution analysis of natural levee formations with the use of dynamic sonar configurations. The increased use of multiple magnetometer arrays and gradiometric sensing of magnetic changes in these same areas can lead research in the direction of refining models in detecting or predicting possible archaeological materials that could date earlier than previously discovered human occupation sites. By illustrating the capabilities of these technologies and how they are used, archaeologists can now refine models and expand the search and protection of cultural resources with refined precision. This refined precision can aid in determining a potentially reduced impact of these areas from development activities. Current models image the avoidance area for archaeological sites based on large structural components of the subsurface that can now potentially be narrowed and better pinpointed. With new survey methods and practices, hazard analyses can improve significantly while also benefitting efforts to understand archaeological landscapes across the North American continent. This paper poses a challenge for archaeologists to utilize and maximize their technological expertise, processing, and analytical capabilities. The paper also introduces the proposal that all marine operators should also consider the benefit of optimizing their survey strategies when approaching development while offshore. As technology continues to develop and offer new methods and higher resolution of the world, all parties can benefit by using the best options capable of bringing data into the next century while keeping up with global science and competition.
{"title":"Advances and Methods in Using, Analyzing, and Interpreting Data in Near and Subsurface Archaeological Contexts","authors":"Eric Swanson","doi":"10.4043/29262-MS","DOIUrl":"https://doi.org/10.4043/29262-MS","url":null,"abstract":"\u0000 \u0000 \u0000 The objective of this paper is to investigate and discuss the increased capability of technology in detecting archaeological sites in a submerged environment. The paper will discuss the dynamic methods using dynamic sonars and magnetometers and how these data are analyzed and interpreted.\u0000 \u0000 \u0000 \u0000 Advances in sonar technology have allowed for more advanced archaeological analytical capabilities. New sub-bottom profiling techniques and analytical capabilities are broadening the resolution in which discreet objects and features can be defined in the sub-surface. Advances in magnetometer processing has also allowed for an advancement in the capability for detecting small magnetic anomalies at depth and creating larger comprehensive profiles of near-surface archaeological materials. Utilizing new processing techniques in conjunction with these technologies opens the door to interpretive methods that can aid archaeologists in identifying potential archaeological sites and can help refine the process of protecting or researching these sites.\u0000 \u0000 \u0000 \u0000 The ongoing work of imaging the near-surface Pleistocene boundary within the North American continental shelf has allowed for higher resolution analysis of natural levee formations with the use of dynamic sonar configurations. The increased use of multiple magnetometer arrays and gradiometric sensing of magnetic changes in these same areas can lead research in the direction of refining models in detecting or predicting possible archaeological materials that could date earlier than previously discovered human occupation sites. By illustrating the capabilities of these technologies and how they are used, archaeologists can now refine models and expand the search and protection of cultural resources with refined precision. This refined precision can aid in determining a potentially reduced impact of these areas from development activities. Current models image the avoidance area for archaeological sites based on large structural components of the subsurface that can now potentially be narrowed and better pinpointed.\u0000 \u0000 \u0000 \u0000 With new survey methods and practices, hazard analyses can improve significantly while also benefitting efforts to understand archaeological landscapes across the North American continent. This paper poses a challenge for archaeologists to utilize and maximize their technological expertise, processing, and analytical capabilities. The paper also introduces the proposal that all marine operators should also consider the benefit of optimizing their survey strategies when approaching development while offshore. As technology continues to develop and offer new methods and higher resolution of the world, all parties can benefit by using the best options capable of bringing data into the next century while keeping up with global science and competition.\u0000","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85142176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With the increasing drive towards high temperature/high pressure wells, particularly in deep water, riser designs are utilising increasingly heavier wall thickness pipe in conventional strength material, up to 50mm wall thickness in 8" and 10" OD X65 linepipe. In deep water, there is a cost preference to utilise steel catenary risers over other riser designs. Such riser designs are challenging existing seamless linepipe manufacturing and girth welding capabilities. Consequently, in order to establish confidence in the practical realisation of such riser designs there is a need to demonstrate: Adequate linepipe material weldability including the achievement of satisfactory HAZ, elevated temperature and sour service properties.Availability of cost effective girth welding solutions for pipeline fabrication. Subsea 7 and Nippon Steel & Sumitomo Metal Corporation (NSSMC) collaborated on a development programme to qualify both linepipe material and welding solutions for the fabrication of pipelines of dimensions 273mm OD in both 35 and 45mm WT SMLS X65 linepipe. The paper will demonstrate the technical feasibility of using heavy wall pipe for demanding riser applications installed subsea by the reel-lay method. The manufacture of seamless pipe in heavy wall thicknesses will be described together with the alloying and thermal treatment concepts involved. Details of the welding solution for pipeline fabrication will be reported together with the details of the scope and results of the qualification programme performed in support of reel-lay pipeline installation.
{"title":"Heavy Wall Linepipe and Welding Solutions for HP/HT Pipelines","authors":"R. Jones, Kenta Yamada","doi":"10.4043/29430-MS","DOIUrl":"https://doi.org/10.4043/29430-MS","url":null,"abstract":"\u0000 With the increasing drive towards high temperature/high pressure wells, particularly in deep water, riser designs are utilising increasingly heavier wall thickness pipe in conventional strength material, up to 50mm wall thickness in 8\" and 10\" OD X65 linepipe. In deep water, there is a cost preference to utilise steel catenary risers over other riser designs. Such riser designs are challenging existing seamless linepipe manufacturing and girth welding capabilities. Consequently, in order to establish confidence in the practical realisation of such riser designs there is a need to demonstrate: Adequate linepipe material weldability including the achievement of satisfactory HAZ, elevated temperature and sour service properties.Availability of cost effective girth welding solutions for pipeline fabrication.\u0000 Subsea 7 and Nippon Steel & Sumitomo Metal Corporation (NSSMC) collaborated on a development programme to qualify both linepipe material and welding solutions for the fabrication of pipelines of dimensions 273mm OD in both 35 and 45mm WT SMLS X65 linepipe.\u0000 The paper will demonstrate the technical feasibility of using heavy wall pipe for demanding riser applications installed subsea by the reel-lay method. The manufacture of seamless pipe in heavy wall thicknesses will be described together with the alloying and thermal treatment concepts involved. Details of the welding solution for pipeline fabrication will be reported together with the details of the scope and results of the qualification programme performed in support of reel-lay pipeline installation.","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85159332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The need for an accurate or at least conservative assessment of wind loads on offshore structures to ensure adequate safety is acknowledged by all stakeholders. A traditional, empirical method that uses a prescriptive approach has been accepted for many decades. Proposed designs are submitted to a regulatory body to demonstrate that requirements using this method are satisfied. A review verifies that the submission satisfies the standard. However, there are questions with respect to the accuracy of this approach that may lead to over-conservative limits in operation. Alternatives exist to the traditional, empirical method to assess wind loads and moments on offshore structures that use both wind tunnel testing and computational fluid dynamics (CFD). Challenges to the use of the alternatives to the traditional method for wind load assessment for regulatory purposes have often pointed to a lack of demonstrable consistency or inaccuracy. Recent work performed under the guidance of the Offshore Committee of the Society of Naval Architects and Marine Engineers has done much to answer the challenges to wind tunnel testing and CFD. However, given the expertise needed to successfully perform wind load assessments using wind tunnel testing or CFD, a traditional regulatory approach that relies on prescriptive standards for acceptance may not be practical. This paper explores different approaches for rules or regulations that can leverage the outcomes of the recent work with sufficient reliability to assess confidently that standards are satisfied. Methods by which equivalents to prescriptive standards may be evaluated and applied in a regulatory context are discussed. Comparisons with similar approaches formulated for use in other maritime fields are also examined.
{"title":"Regulatory Approaches for Wind Load Assessments of Offshore Structures","authors":"W. Peters","doi":"10.4043/29285-MS","DOIUrl":"https://doi.org/10.4043/29285-MS","url":null,"abstract":"\u0000 The need for an accurate or at least conservative assessment of wind loads on offshore structures to ensure adequate safety is acknowledged by all stakeholders. A traditional, empirical method that uses a prescriptive approach has been accepted for many decades. Proposed designs are submitted to a regulatory body to demonstrate that requirements using this method are satisfied. A review verifies that the submission satisfies the standard. However, there are questions with respect to the accuracy of this approach that may lead to over-conservative limits in operation.\u0000 Alternatives exist to the traditional, empirical method to assess wind loads and moments on offshore structures that use both wind tunnel testing and computational fluid dynamics (CFD). Challenges to the use of the alternatives to the traditional method for wind load assessment for regulatory purposes have often pointed to a lack of demonstrable consistency or inaccuracy.\u0000 Recent work performed under the guidance of the Offshore Committee of the Society of Naval Architects and Marine Engineers has done much to answer the challenges to wind tunnel testing and CFD. However, given the expertise needed to successfully perform wind load assessments using wind tunnel testing or CFD, a traditional regulatory approach that relies on prescriptive standards for acceptance may not be practical.\u0000 This paper explores different approaches for rules or regulations that can leverage the outcomes of the recent work with sufficient reliability to assess confidently that standards are satisfied. Methods by which equivalents to prescriptive standards may be evaluated and applied in a regulatory context are discussed. Comparisons with similar approaches formulated for use in other maritime fields are also examined.","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88136939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper discusses the requirements for a "next-generation" subsea control system and provides a description of the proposed setup/architecture. Requirements for "next-generation" subsea control focuses on requirements for "digitalization" and Industry 4.0 capabilities. Existing subsea control systems today are intended for and used to control hydraulic valves in subsea production setups. The proposed "next-generation" subsea control system is specified, designed and built for an all-electric process control setup, with requirements for extensive usage of digitalization toolboxes. Primary requirements for the "next-generation" subsea control system would be deterministic behavior and latency in the millisecond range for the control of operations part/signals/objects, while at the same time generating large amounts of high quality and highly accurate time-stamped condition monitoring data to be used in the digitalization setup. The proposed concept integrates subsea control and historian systems directly into the existing topsides control and historian systems. Implementation of an anti-surge control system will be used as an example to illustrate the concept for control of operations, and the use of artificial intelligence (AI) and historical stored data would be used as examples for topside digitalization techniques used on subsea installed equipment. Removing boundaries between topsides and subsea automation as suggested in this paper provides options to use already available toolboxes for digitalization of topsides assets on similar subsea components. The proposed open architecture control system would also easily interface directly to any cloud-based solution with standard interfaces or well-defined application program interfaces (APIs). Economic benefits of implementing an open-architecture control system would include CAPEX and OPEX reductions, while at the same time creating a "future-proof" system that allows for the addition of digitalization options. Subsea data would be delivered and stored with higher quality, providing operators with the option to look retrospectively and evaluate historian data based on knowledge to be obtained in the future. Moreover, having one integrated control system provides better protection against cyberthreats, as it eliminates the requirement for several systems, which need to be updated and maintained during the lifetime of the installation. Various predictions and thoughts about the future of subsea controls beyond the proposed "next-generation" subsea control system will also be included in this paper.
{"title":"Digitalization Goes Subsea","authors":"Karstein Kristiansen","doi":"10.4043/29226-MS","DOIUrl":"https://doi.org/10.4043/29226-MS","url":null,"abstract":"\u0000 This paper discusses the requirements for a \"next-generation\" subsea control system and provides a description of the proposed setup/architecture. Requirements for \"next-generation\" subsea control focuses on requirements for \"digitalization\" and Industry 4.0 capabilities. Existing subsea control systems today are intended for and used to control hydraulic valves in subsea production setups. The proposed \"next-generation\" subsea control system is specified, designed and built for an all-electric process control setup, with requirements for extensive usage of digitalization toolboxes.\u0000 Primary requirements for the \"next-generation\" subsea control system would be deterministic behavior and latency in the millisecond range for the control of operations part/signals/objects, while at the same time generating large amounts of high quality and highly accurate time-stamped condition monitoring data to be used in the digitalization setup. The proposed concept integrates subsea control and historian systems directly into the existing topsides control and historian systems. Implementation of an anti-surge control system will be used as an example to illustrate the concept for control of operations, and the use of artificial intelligence (AI) and historical stored data would be used as examples for topside digitalization techniques used on subsea installed equipment.\u0000 Removing boundaries between topsides and subsea automation as suggested in this paper provides options to use already available toolboxes for digitalization of topsides assets on similar subsea components. The proposed open architecture control system would also easily interface directly to any cloud-based solution with standard interfaces or well-defined application program interfaces (APIs).\u0000 Economic benefits of implementing an open-architecture control system would include CAPEX and OPEX reductions, while at the same time creating a \"future-proof\" system that allows for the addition of digitalization options. Subsea data would be delivered and stored with higher quality, providing operators with the option to look retrospectively and evaluate historian data based on knowledge to be obtained in the future.\u0000 Moreover, having one integrated control system provides better protection against cyberthreats, as it eliminates the requirement for several systems, which need to be updated and maintained during the lifetime of the installation.\u0000 Various predictions and thoughts about the future of subsea controls beyond the proposed \"next-generation\" subsea control system will also be included in this paper.","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89918774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ishan Mons, V. Veedu, J. Pollock, G. Nakafuji, H. Elshahawi, K. Jim, M. Hadmack
High speed wireless communication has proven elusive in subsea environments due to the inherent bandwidth limitations of acoustics and range limitations of other transmission modalities. A truly connected subsea system necessitates a high-speed, resilient architecture that can enable the integration of new sensor technologies and edge analytics and allow closed-loop monitoring and control of subsea operations for integrity monitoring and optimization. Like terrestrial Internet of Things applications, the realization of this "digital subsea" vision requires the application of high speed, point-to-point wireless technologies to complement rather than replace "hard-wired" communications such as optical fiber or acoustic systems. This work addresses the development of ULTRA (Underwater LASER Telemetry and Remote Access), an ultra-long range underwater laser communications system for use in critical points of the subsea communications architecture to increase reliability, operational flexibility, and reduce communication system maintenance associated with physical subsea connections. To demonstrate the data capacity and range of ULTRA, a subscale laboratory point-to-point wireless laser communication system was constructed with the flexibility to transmit through either air or water. The test system used power and modulation frequencies for air, fresh water, and different qualities of seawater. Optical and RF encoding methodologies were implemented to facilitate and characterize data transmission through the various media. The laboratory experiment used a subscale, filtered, and attenuated 5 mW blue-green laser in a 22-meter folded path configuration to demonstrate real-time data transmission at 312 Megabit per Second (Mbps) data rate using single channel Quadrature Phase Shift Keying (QPSK) modulation. A field prototype ULTRA system will use an unattenuated 5 mW laser that can reach approximately 280-meter range at 312 Mbps in clear conditions, which are typical of deepwater subsea. The selection of laser power and data rate are considered operational tradeoffs in environments where underwater vehicles operate. The extended range of ULTRA can enable various use cases to greatly augment subsea data communications capacity to enable the "Digital Subsea".
{"title":"Subsea Broadband Using Underwater LASER Telemetry and Remote Access","authors":"Ishan Mons, V. Veedu, J. Pollock, G. Nakafuji, H. Elshahawi, K. Jim, M. Hadmack","doi":"10.4043/29303-MS","DOIUrl":"https://doi.org/10.4043/29303-MS","url":null,"abstract":"\u0000 High speed wireless communication has proven elusive in subsea environments due to the inherent bandwidth limitations of acoustics and range limitations of other transmission modalities. A truly connected subsea system necessitates a high-speed, resilient architecture that can enable the integration of new sensor technologies and edge analytics and allow closed-loop monitoring and control of subsea operations for integrity monitoring and optimization. Like terrestrial Internet of Things applications, the realization of this \"digital subsea\" vision requires the application of high speed, point-to-point wireless technologies to complement rather than replace \"hard-wired\" communications such as optical fiber or acoustic systems. This work addresses the development of ULTRA (Underwater LASER Telemetry and Remote Access), an ultra-long range underwater laser communications system for use in critical points of the subsea communications architecture to increase reliability, operational flexibility, and reduce communication system maintenance associated with physical subsea connections.\u0000 To demonstrate the data capacity and range of ULTRA, a subscale laboratory point-to-point wireless laser communication system was constructed with the flexibility to transmit through either air or water. The test system used power and modulation frequencies for air, fresh water, and different qualities of seawater. Optical and RF encoding methodologies were implemented to facilitate and characterize data transmission through the various media. The laboratory experiment used a subscale, filtered, and attenuated 5 mW blue-green laser in a 22-meter folded path configuration to demonstrate real-time data transmission at 312 Megabit per Second (Mbps) data rate using single channel Quadrature Phase Shift Keying (QPSK) modulation. A field prototype ULTRA system will use an unattenuated 5 mW laser that can reach approximately 280-meter range at 312 Mbps in clear conditions, which are typical of deepwater subsea. The selection of laser power and data rate are considered operational tradeoffs in environments where underwater vehicles operate. The extended range of ULTRA can enable various use cases to greatly augment subsea data communications capacity to enable the \"Digital Subsea\".","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77565696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fitness-for-service (FFS) assessments are critical to the integrity management of offshore and subsea assets. Decisions regarding continued service life or the need for corrective action for damaged structures pivot on accurate FFS assessment results. While FFS assessments using failure assessment diagrams (FAD) and finite element method (FEM) have been successfully implemented on simple and regular geometries, they are not suitable for structures with complex geometries, transition of failure modes, presence of residual stress, and nonlinear fracture toughness. Extended finite element method (XFEM), a fracture mechanics-based approach enriched by extra functions around a crack, is capable of considering the above mentioned scenarios and evaluating the crack behavior. This paper demonstrates the performance of XFEM and validates the results obtained from XFEM. First, XFEM is implemented in assessing a stationary crack on ASTM Compact Test (CT) specimen to calculate the stress intensity factor (SIF) which the obtained results deviate from the analytical solution by less than 6% for various crack length cases. Following that, a cracked plate case treated with cold expansion technique is investigated. Its remaining fatigue life is obtained by simulating fatigue crack growth, under two sets of residual stresses generated by different mandrel diameters. The results are then compared to the crack arrest hole (CAH) approach. Through these case studies, XFEM shows adequacy for FFS applications. XFEM facilitates the modeling of the crack surface, and eliminates the need to remesh for crack growth analysis. Arbitrary structure geometries and loading combinations can be directly used in XFEM since the stress and strain responses are calculated in a conventional FEM framework. This means that the presence of local corrosion and dents, as well as transition of failure modes can be accounted for. The residual stress effect can be accurately calculated and considered for SIF calculation. Although XFEM appears to be a good solution for FFS application, adequate caution should be given to the mesh size selection and mesh orientation because they may cause slight or noticeable fluctuation of results. Therefore, a mesh sensitivity study is recommended.
{"title":"Implementation of XFEM for Fitness-For-Service Assessments in Life Extension and Damaged Structure Applications","authors":"Mengxi Liu, Smarty Mathew John, Jessie Lin, Amanda Massingill","doi":"10.4043/29488-MS","DOIUrl":"https://doi.org/10.4043/29488-MS","url":null,"abstract":"Fitness-for-service (FFS) assessments are critical to the integrity management of offshore and subsea assets. Decisions regarding continued service life or the need for corrective action for damaged structures pivot on accurate FFS assessment results. While FFS assessments using failure assessment diagrams (FAD) and finite element method (FEM) have been successfully implemented on simple and regular geometries, they are not suitable for structures with complex geometries, transition of failure modes, presence of residual stress, and nonlinear fracture toughness. Extended finite element method (XFEM), a fracture mechanics-based approach enriched by extra functions around a crack, is capable of considering the above mentioned scenarios and evaluating the crack behavior. This paper demonstrates the performance of XFEM and validates the results obtained from XFEM.\u0000 First, XFEM is implemented in assessing a stationary crack on ASTM Compact Test (CT) specimen to calculate the stress intensity factor (SIF) which the obtained results deviate from the analytical solution by less than 6% for various crack length cases. Following that, a cracked plate case treated with cold expansion technique is investigated. Its remaining fatigue life is obtained by simulating fatigue crack growth, under two sets of residual stresses generated by different mandrel diameters. The results are then compared to the crack arrest hole (CAH) approach.\u0000 Through these case studies, XFEM shows adequacy for FFS applications. XFEM facilitates the modeling of the crack surface, and eliminates the need to remesh for crack growth analysis. Arbitrary structure geometries and loading combinations can be directly used in XFEM since the stress and strain responses are calculated in a conventional FEM framework. This means that the presence of local corrosion and dents, as well as transition of failure modes can be accounted for. The residual stress effect can be accurately calculated and considered for SIF calculation. Although XFEM appears to be a good solution for FFS application, adequate caution should be given to the mesh size selection and mesh orientation because they may cause slight or noticeable fluctuation of results. Therefore, a mesh sensitivity study is recommended.","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76998498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hans Fredrik Lindøen Kjellnes, Trond William Jenssen, Joakim Almqvist, Petter Solberg, Carsten Falck Russenes
Subsea boosting has been building a track record at increasing depths and higher pressures. This has introduced certain new challenges. Continuous development of the technology has been required to maintain the historical high reliability and operability. This paper identifies operational challenges associated with a specific deepwater field and how they were resolved. The close collaboration between the operator's and the pump supplier's teams is emphasized as a success-factor. Insight is given into the development team's problem-solving strategy, as well as the applied technology itself. Extensive use of digital tools such as advanced dynamic modelling and virtual prototyping has been applied to debug concepts ahead of physical prototyping. This resulted in a fast track project with only very few time-consuming and expensive re-iterations. In 2014 the world's deepest seabed boosting pump system was successfully installed and commissioned. The permanent real-time condition monitoring system allowed the pump manufacturer to remotely monitor the pump performance. During the first few months of operation, it was determined that the shut-in pressure gradient was significantly steeper than specified. The production pressure build-up following a pump stop was more abrupt than the pump's barrier fluid pressure control system was designed to deal with. Because the gradient of the pressure increase couldn't be altered, a limitation on the pump's maximum pressure drawdown was immediately put in place. This was done to minimize the amplitude of the pressure increase on shut-in, and to prevent the production pressure from exceeding the pump's barrier fluid pressure. Without such a limitation, this condition could result in a pump breakdown. Continuous operation with this constraint in place would lead to significant curtailment once additional pressure drawdown was required to maintain the nameplate production. Seabed pumps are equipped with a barrier fluid system, which is regarded among the main success factors leading to the high meantime to failure. The barrier fluid system provides the pump with clean fluid at a correct pressure. The barrier fluid is used for lubrication of bearings and seals, heat transfer, and electric insulation. It also constitutes a barrier, hence its name, for any production fluid ingress into the electric motor through pressure control. The pressure is being closed-loop regulated to stay within a certain band above the production pressure. Barrier fluid is conveyed between host facility and the subsea pump through small-bore tubing in the umbilical. Thus, quick volume exchanges between topside and subsea is limited. As the umbilical length increase, the response time, as given by speed of sound, also becomes a limiting factor. A subsea pressure control system is the most common solution in the industry for larger depths and long tie-backs. As the well pressures were depleting for the described deepwater field, the drawdown
{"title":"Development of Novel Pressure Control for Subsea Pumps and Compressors","authors":"Hans Fredrik Lindøen Kjellnes, Trond William Jenssen, Joakim Almqvist, Petter Solberg, Carsten Falck Russenes","doi":"10.4043/29563-MS","DOIUrl":"https://doi.org/10.4043/29563-MS","url":null,"abstract":"\u0000 Subsea boosting has been building a track record at increasing depths and higher pressures. This has introduced certain new challenges. Continuous development of the technology has been required to maintain the historical high reliability and operability. This paper identifies operational challenges associated with a specific deepwater field and how they were resolved. The close collaboration between the operator's and the pump supplier's teams is emphasized as a success-factor. Insight is given into the development team's problem-solving strategy, as well as the applied technology itself. Extensive use of digital tools such as advanced dynamic modelling and virtual prototyping has been applied to debug concepts ahead of physical prototyping. This resulted in a fast track project with only very few time-consuming and expensive re-iterations.\u0000 In 2014 the world's deepest seabed boosting pump system was successfully installed and commissioned. The permanent real-time condition monitoring system allowed the pump manufacturer to remotely monitor the pump performance. During the first few months of operation, it was determined that the shut-in pressure gradient was significantly steeper than specified. The production pressure build-up following a pump stop was more abrupt than the pump's barrier fluid pressure control system was designed to deal with. Because the gradient of the pressure increase couldn't be altered, a limitation on the pump's maximum pressure drawdown was immediately put in place. This was done to minimize the amplitude of the pressure increase on shut-in, and to prevent the production pressure from exceeding the pump's barrier fluid pressure. Without such a limitation, this condition could result in a pump breakdown. Continuous operation with this constraint in place would lead to significant curtailment once additional pressure drawdown was required to maintain the nameplate production.\u0000 Seabed pumps are equipped with a barrier fluid system, which is regarded among the main success factors leading to the high meantime to failure. The barrier fluid system provides the pump with clean fluid at a correct pressure. The barrier fluid is used for lubrication of bearings and seals, heat transfer, and electric insulation. It also constitutes a barrier, hence its name, for any production fluid ingress into the electric motor through pressure control. The pressure is being closed-loop regulated to stay within a certain band above the production pressure.\u0000 Barrier fluid is conveyed between host facility and the subsea pump through small-bore tubing in the umbilical. Thus, quick volume exchanges between topside and subsea is limited. As the umbilical length increase, the response time, as given by speed of sound, also becomes a limiting factor. A subsea pressure control system is the most common solution in the industry for larger depths and long tie-backs.\u0000 As the well pressures were depleting for the described deepwater field, the drawdown","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87217669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
While there is a lot of talk about Big Data Analytics, Internet of Things (IoT), Artificial Intelligence (AI), Real Time Monitoring (RTM), Digital Twin and other methodologies, all of them require, not only data, but accurate, reliable data. This paper describes a new and innovative inspection methodology that combines 3D laser scanning and precise 3D Geometric Dimensioning & Tolerancing (GD&T) metrology data with advanced Non-Destructive Testing (NDT) results. This data is then combined in digital 3D space to give an accurate representation of current equipment condition and mechanical integrity of critical offshore assets. Such inspection and testing can be conducted during manufacturing as a quality check, creating digital baseline records, or on deck during operations, saving significant downtime and costs. By including metrology and phased array, the described inspection methodology can provide precise digital data and specialized 3D reports that will satisfy not only compliance and regulatory efforts in a more objective manner, but also assist original equipment manufacturers (OEMs), drilling contractors and operators by supplying conclusive and accurate data of equipment condition. This data, based on in-situ NDT and Geometric Dimensioning & Tolerancing measurement information, will support Digital Twin data and operational and maintenance decisions that will preserve the integrity, safety, and availability of the assets. This innovative inspection solution can form part of a Condition-Based Maintenance (CBM) program where operators can move from time-based programs and use the digital data to determine future equipment performance, work scope, and schedules while maintaining a complete and updated digital condition record throughout the lifecycle of the equipment. The program may predict and prevent problems at early stages, provide strategies that will simplify maintenance activities, and potentially identify manufacturing flaws. More importantly, it can create historical digital data that will change the way the drilling industry operates and satisfy what regulatory agencies have been seeking since the implementation of the new well control rule.
{"title":"Innovative Digital Inspection Methods","authors":"Stephen Anderson, Sigve Barvik, Chad Rabitoy","doi":"10.4043/29387-MS","DOIUrl":"https://doi.org/10.4043/29387-MS","url":null,"abstract":"\u0000 While there is a lot of talk about Big Data Analytics, Internet of Things (IoT), Artificial Intelligence (AI), Real Time Monitoring (RTM), Digital Twin and other methodologies, all of them require, not only data, but accurate, reliable data. This paper describes a new and innovative inspection methodology that combines 3D laser scanning and precise 3D Geometric Dimensioning & Tolerancing (GD&T) metrology data with advanced Non-Destructive Testing (NDT) results. This data is then combined in digital 3D space to give an accurate representation of current equipment condition and mechanical integrity of critical offshore assets. Such inspection and testing can be conducted during manufacturing as a quality check, creating digital baseline records, or on deck during operations, saving significant downtime and costs.\u0000 By including metrology and phased array, the described inspection methodology can provide precise digital data and specialized 3D reports that will satisfy not only compliance and regulatory efforts in a more objective manner, but also assist original equipment manufacturers (OEMs), drilling contractors and operators by supplying conclusive and accurate data of equipment condition. This data, based on in-situ NDT and Geometric Dimensioning & Tolerancing measurement information, will support Digital Twin data and operational and maintenance decisions that will preserve the integrity, safety, and availability of the assets.\u0000 This innovative inspection solution can form part of a Condition-Based Maintenance (CBM) program where operators can move from time-based programs and use the digital data to determine future equipment performance, work scope, and schedules while maintaining a complete and updated digital condition record throughout the lifecycle of the equipment. The program may predict and prevent problems at early stages, provide strategies that will simplify maintenance activities, and potentially identify manufacturing flaws. More importantly, it can create historical digital data that will change the way the drilling industry operates and satisfy what regulatory agencies have been seeking since the implementation of the new well control rule.","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86308466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. S. Rovina, C. J. Valença, F. M. Passarelli, S. Balint
This paper uses a case study approach to present the challenges to develop a large and thick oil carbonate reservoir that is full of opportunities and uncertainties. The Libra block, located in Santos Basin ultra-deep water, in Brazil, has been developed under a Production Sharing Contract that was awarded to a Consortium where PETROBRAS is the operator in partnership with SHELL, TOTAL, CNOOC Limited and CNPC. This document will briefly present the de-risking plan, and detail the EWT Program implementation and its impact on the Mero area development, which consists of up to 4 (four) mega projects and altogether represents over 20 billion dollars in CAPEX investment. In addition, the results will show how the achievements achieved by the EWT project provided an extensive technological legacy to the offshore oil & gas industry.
{"title":"Extend Well Test EWT Libra Project Overview and Technological Highlights","authors":"P. S. Rovina, C. J. Valença, F. M. Passarelli, S. Balint","doi":"10.4043/29533-MS","DOIUrl":"https://doi.org/10.4043/29533-MS","url":null,"abstract":"\u0000 This paper uses a case study approach to present the challenges to develop a large and thick oil carbonate reservoir that is full of opportunities and uncertainties. The Libra block, located in Santos Basin ultra-deep water, in Brazil, has been developed under a Production Sharing Contract that was awarded to a Consortium where PETROBRAS is the operator in partnership with SHELL, TOTAL, CNOOC Limited and CNPC. This document will briefly present the de-risking plan, and detail the EWT Program implementation and its impact on the Mero area development, which consists of up to 4 (four) mega projects and altogether represents over 20 billion dollars in CAPEX investment. In addition, the results will show how the achievements achieved by the EWT project provided an extensive technological legacy to the offshore oil & gas industry.","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87771808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
X. Long, G. Tucker, P. Gibbs, Z. Westgate, Alberto Díaz, A. Senanayake
The geotechnical site characterization process typically begins with an assessment of the soil lithology, the in situ stress state, and the geostatic stress history of the formation, which involves identification of soil types and an evaluation of the preconsolidation, or effective yield, stress. The preconsolidation stress is defined as the maximum past stress physically and/or mechanically applied to the soil, representing the demarcation between normally consolidated (NC) and overconsolidated (OC) states. This paper presents an assessment of the preconsolidation stress of Atlantic Outer Continental Shelf (OCS) sediments within the zone of influence for offshore renewable wind turbine foundations, based on laboratory oedometer test data and cone penetration test (CPTu) data. Atlantic OCS sediments comprise a complex layering of clays, sands, and silts, classified using physical (textural) characteristics, including visual description, grain size distribution, and soil plasticity-based or CPTu data-based soil behavior type (SBT) charts. Soil classification for a variety of OCS sediment types from SBT charts, the Unified Soil Classification System (USCS), and ISO standard 14688-2 (2018) is compared and described. Predicted preconsolidation stresses are compared across several commonly used industry methods, and prediction accuracies are discussed in the context of soil type, minerology, and microstructure. Guidance is provided on appropriate site investigation (SI) techniques to allow characterization of these influential properties.
{"title":"Soil Classification and Evaluation of Preconsolidation Stress of Atlantic Outer Continental Shelf OCS Sediments from Oedometer and Cone Penetration Testing","authors":"X. Long, G. Tucker, P. Gibbs, Z. Westgate, Alberto Díaz, A. Senanayake","doi":"10.4043/29541-MS","DOIUrl":"https://doi.org/10.4043/29541-MS","url":null,"abstract":"\u0000 The geotechnical site characterization process typically begins with an assessment of the soil lithology, the in situ stress state, and the geostatic stress history of the formation, which involves identification of soil types and an evaluation of the preconsolidation, or effective yield, stress. The preconsolidation stress is defined as the maximum past stress physically and/or mechanically applied to the soil, representing the demarcation between normally consolidated (NC) and overconsolidated (OC) states.\u0000 This paper presents an assessment of the preconsolidation stress of Atlantic Outer Continental Shelf (OCS) sediments within the zone of influence for offshore renewable wind turbine foundations, based on laboratory oedometer test data and cone penetration test (CPTu) data. Atlantic OCS sediments comprise a complex layering of clays, sands, and silts, classified using physical (textural) characteristics, including visual description, grain size distribution, and soil plasticity-based or CPTu data-based soil behavior type (SBT) charts.\u0000 Soil classification for a variety of OCS sediment types from SBT charts, the Unified Soil Classification System (USCS), and ISO standard 14688-2 (2018) is compared and described. Predicted preconsolidation stresses are compared across several commonly used industry methods, and prediction accuracies are discussed in the context of soil type, minerology, and microstructure. Guidance is provided on appropriate site investigation (SI) techniques to allow characterization of these influential properties.","PeriodicalId":11149,"journal":{"name":"Day 1 Mon, May 06, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90206796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：