bluuebunny/crossref_metadata_2025 huggingface dataset:
Seismic Inversion for Site Characterization: When, Where and Why Should We Use It?
Authors: Vardy M. E. , Clare M. A. , Vanneste M. , Forsberg C. F. , Dix J. K.
Published: April 2018

The application of seismic inversion techniques to the foundation and drilling top hole zones has garnered significant interest in recent years. The shift towards more geologically complex and deeper water sites, combined with the global economic climate, has driven a requirement for more cost-effective site characterisation. More often used by the exploration industry, seismic inversion has been touted as a potentially valuable tool for quantifying the spatial and depth variability in sediment properties. In doing so, this approach can reduce the risk of encountering unforeseen ground conditions and the need for excessive over-design. Despite its potential, the inversion of high-resolution seismic data has yet to see widespread use, leaving unanswered questions regarding how and where this tool can best fit into the site characterization work flow.

We test the potential usefulness of seismic inversion using a range of existing site investigation data sets. We apply several different inversion methods, including acoustic impedance and seismic quality factor inversion, as well as artificial neural network multi-attribute regression, to tackle end-member potential uses. First, explore early-phase potential uses, showing how seismic quality factor and acoustic impedance inversion can be used to capture the spatial variability in facies architecture and bulk sediment properties that could be used in appraisal and pre-FEED studies to optimize borehole and penetrometer (CPT) depths/locations and to ensure effective site-wide characterization. Second, we apply a combined acoustic impedance and artificial neural network workflow to link seismic properties with CPT profiles. These results demonstrate the potential late-phase use of seismic inversion for short-range interpolation/extrapolation of more complex geotechnical properties through the generation of synthetic CPT profiles useful for infrastructure design and micro-siting late in the development cycle.

While not a comprehensive list of applications, together these examples illustrate how seismic inversion can be utilized throughout the development cycle. If the required objectives are clearly defined and an appropriate inversion workflow developed, seismic inversion can help to reduce uncertainty in site-wide characterization and drive efficiencies in layout and design studies throughout a project lifetime.
Successful Management of Major Marine Operations for the Hebron Project
Authors: Perry R. , Overstake M. , Hagen O. , McCarthy R.
Published: April 2018

It is well known in the industry that the environment for all offshore oil and gas marine operations has unique challenges the world over. However, when operating in a sub-arctic region with notoriously difficult sea states, regular encounters with sea ice, icebergs, strong winds, thick fog and numerous forms of solid and liquid precipitation, the challenges become a major consideration for even the most straight forward task. It was in this very environment in Newfoundland and Labrador (NL), Canada, the Hebron Project safely and successfully executed a number of very complex, industry first, major marine operations. Successful management of these major operations was only possible due to a strong, experienced team who were able to balance critical technical planning processes with an appropriate risk based approach to decision making. The basis for this approach to planning and executing these marine activities for the Hebron Project will be explained in this paper, including some of the key success factors that enabled the team to overcome many safety, environmental and technical challenges that were encountered.
Balanced Maturity Model for Oil and Gas Portfolio of Assets
Authors: Bastos Marcelo
Published: April 2018

Capital-intensive projects are inherent to the oil industry, which requires large upfront capital expenditure and long-term paybacks. Diversification strategies are regularly used by oil companies to avoid high exposure to big projects and their geological, fiscal, cost, and political risks. Amongst such risks, oil price plays a pivotal role as the main variable driving project returns.

The purpose of this paper is to analyze these risks, with a special emphasis on oil price, and propose a systematic method to manage a balanced portfolio, considering different risks and diversification strategies. Oil companies must assess the size of their bets in exploration and development, evaluate farm-ins and farm-outs, invest in potentially disruptive energy sources, and downstream integration.

These combined alternatives must target a portfolio with diversified maturity that leads to a varied temporal price exposure and long-term financial robustness. The model proposed in this paper lays out a reference portfolio based on a typical selection of projects. Projects are classified as a family, its members, and financial structure. Each family must have enough breadwinners to sustain the other members, investing in the future of the kids, and complement the retired members’ income. This model offers companies a reference to consciously select a strategy according to their higher or lower risk profile.
Validation of Multiphase Modeling of a Horizontal Liquid-Liquid Separator in Fluent and STAR-CCM+
Authors: McCleney A. B. , Green S. T. , Owston R. A.
Published: April 2018

Computational simulations of a full-scale, horizontal liquid-liquid gravity separator have been undertaken by Southwest Research Institute (SwRI®) to model the batch separation of oil and water flow in two different software packages. Separator modeling using computational fluid dynamics (CFD) represents a powerful and economical option for design, but caution must be used in the setup and interpretation of data. Many examples are available in literature of poor agreement between simulation results and experimental/field data. Results require interpretation before taking them at face value due to the complexity of the various submodels that can be utilized. This work offers an evaluation of multiphase flow modeling techniques in both ANSYS® Fluent® and in Siemens PLM STAR-CCM+®, and provides a unique comparison between the CFD solvers that cover a broad range of flow rates, water cuts, and viscosities. Verification of the accuracy of each software package to reproduce empirical results while reducing computational resources has been accomplished.

The performance of a horizontal gravity separator with perforated baffles has been investigated using CFD. The simulations were carried out using an Eulerian-Eulerian multiphase approach, using monodisperse water droplets in an oil-continuous phase. Separation efficiencies and fluid concentration percentages at several locations throughout the test separator were compared against experimental results for a wide range of inlet flow rates, water cuts, and oil viscosities. Initial computational results indicated that the horizontal liquid-liquid separator can be modeled within 7% accuracy of the local experimental separation efficiency values for the various test conditions in both software packages. An additional simulation with a modification to a known drag model in Fluent showed a significant improvement to the oil-in-water (OiW) concentration in comparison to the same simulation conducted in STAR-CCM+. This effort demonstrates the capability of reliable modeling of multiphase flow fields inside of horizontal gravity separators and offers a viable option for aiding in the design of separation equipment.
Integrating Core Porosity and Well Logging Interpretations for Multivariate Permeability Modeling through Ordinary Kriging and Co-Kriging Algorithms
Authors: Al-Mudhafar Watheq J.
Published: April 2018

Estimation of core permeability as a function of well logging records is a pivotal task in reservoir characterization as it is affected by data sparseness, distinct scales, various sources, and lithology structures. In this paper, three specific dataset formats of a well logging and core measurements were considered for the core permeability modeling and prediction using the ordinary kriging and co-kriging interpolation algorithms. The dataset were used as complete dataset of multi-facies and two split datasets of shale- and sand-based measurements. More specifically, the ordinary kriging was first used to model the core permeability as a function of the well logging records only through constructing the variogram given the three mentioned dataset types. The same procedure was repeated by adopting the cross-variogram approach to model the core permeability as a primary factor along with core porosity as a secondary factor, both as a function of the well logging records. The well logging attributes, which were obtained from an oil well, include neutron porosity and water saturation given the well depth.

The cross-variogram was adopted to quantify the dissimilarity between known and unknown data for the co-kriging interpolation to provide linear coregionalization modeling of core permeability and porosity. The modeling and prediction accuracy of core permeability through the ordinary kriging and co-kriging algorithms were assessed by applying the leave-one-out cross validation in addition to the visual mismatch between predicted and observed core permeability. Results illustrated that co-kriging interpolation led to a more accurate permeability prediction than the ordinary kriging by achieving the highest adjusted R-square and the lowest root mean square error. The integrated workflow of ordinary kriging and co-kriging was applied on a dataset from an oil well in sandstone reservoir in the South Rumaila oil field, Southern Iraq.
ETH-HCRAW a Cost Effective Flexible Pipe for Active Heating
Authors: Lefer Bruno , Dessaint Renaud , Marchand Didier
Published: April 2018

To address flow assurance challenges, Integrated Production Bundle (ETH-IPB) and Heating Cables Replacing Armour Wires (ETH-HCRAW) have been developed. These two technologies use electrical cables, which provide heat to the fluid by Joule effect. They are different in their design, efficiency and cost, and thus on their application domains. This paper details the design, the qualification and the identified envelop of use of the ETH-HCRAW.

The pioneer flexible pipe with active heating technology was ETH-HCRAW, i.e. flexible pipe with electrical cables integrated in the tensile armour layers for active heating and such application is developed in the paper. The integration of the active heating in the flexible and the terminations is presented. The overall qualification of this technology is described considering two different levels. Firstly, the qualification of the components of the electrical system through extensive electrical and mechanical tests is developed. Then, the global mechanical behavior and the reliability of the overall system are demonstrated by a phase of full scale tests.

Such solution based on integrated electrical cables has been demonstrated to be a safe and effective technology for active heating on flexible pipe through dedicated R&D development back in the early 2000’s. This paper presents the latest developments that enable to position the ETH-HCRAW technology as leading solution for active heating with the advantages of flexible pipes. ETH-HCRAW facilitates the exploitation of deep water projects and long tie back by limiting the temperature losses along the lines. Active heating, by increasing the temperature of the fluid, enhances flow assurance for complex and viscous fluids by reducing the viscosity and reduces wax appearance in the lines. Finally, this technology tackles the formation of hydrates by maintaining a minimum temperature during shut down and start-up phases allowing to remain outside the hydrate formation conditions.

ETH-HCRAW is an attractive and cost effective active heating solution with a broad possible domain of application. This technology offers many advantages in terms of flexibility of operation especially for hydrate and wax management. This paper details the numerous advantages and the limitations of this technology compared to other active heating technologies.
Assessment of Pipelines for Manmade Hazards
Authors: Akinci N. O. , Kumar A. , Simpson N. , Dai X. , Guinard M.
Published: April 2018

Well intervention operations at shallow water depth typically require utilization of a jack-up rig nearby a fixed platform and pipelines depending on orientation of platform and drilling rig approach angle. Interaction of jack-up spudcans with platform piles have been studied by many researchers and generic guidelines are provided in several design codes. However, interaction of spudcans or other potential earthwork related activities with nearby pipelines and potential long-term integrity effects are not captured in the current state of the art. The objective of this study is to present findings from analytical assessment of soil displacement and pipeline interaction studies.

This paper summarizes findings and observations from case studies, and provides guidelines regarding extent of spudcan influence distance for pipelines. Non-linear finite element analysis tool Abaqus [1] was utilized for the assessment of spudcan-soil-pipeline interaction. Response of soft clay type soils were simulated using Coupled Eulerian-Lagrangian (CEL) approach like that for a mud slide scenario. Spudcan extraction and subsequent soil collapse potential were investigated as part of this study. Generalized recommendations were developed after running sensitivity studies with varying soil and pipeline parameters. Pipeline buckling and potential integrity implications due to soil movement are discussed.

It was observed that pipelines within one diameter of the spudcan are susceptible to increased stresses due to soil movements at the surface during spudcan driving and pull-out operations. The resulting imposition of localized out-of-straightness could increase the risk of subsequent pipeline buckling under operating conditions. Collapse risks for soil after spudcan extraction needs to be evaluated on a case by case basis. Spudcan extraction conditions are more critical compared to spudcan driving for soil displacements and soil degradation. Aging pipeline systems pose an additional challenge as some of those pipelines may not meet current design code requirements.

The case studies and generalized recommendations presented in this study are expected to provide information for screening level assessments and requirements for further analysis. Although the pipeline related risks have been well known in the industry, guidelines for pipeline clearance requirements and a simplified method to estimate pipe stresses are not available in the literature. The recommendations presented in this study would enable assessing the spudcan pipeline interaction risks in a practical way.
Advancements in Guidance for the Specification and Assessment of Mooring Steel Wire Rope
Authors: Potts Andrew , Jayasinghe Kanishka , Kilner Andrew , Melchers Robert , Chaplin C. R.
Published: April 2018

Prior to the SCORCH JIP, industry guidance for steel wire ropes specified only a maximum service life for various rope constructions, providing no insight into the corrosion degradation processes affecting mooring ropes at different locations in the mooring line and under different working conditions, or to potential differences in manufacture. One of the objectives of the SCORCH JIP was to address this gap in knowledge by providing design guidance on the specification of mooring wire ropes and analytical tools to estimate the design service life of mooring wire ropes for particular site conditions, especially in tropical waters.

In the wire rope component of the JIP, field recovered specimens were examined and field tests on wires and wire ropes were performed to quantify the effects of external factors driving degradation of wire ropes in marine environments, including: protective coating; blocking compound, temperature, flow velocity, oxygenation and dynamic loading. Failure modes for wire rope were analysed based on the examination of recovered samples from in- service wire ropes, inspection records from different floating production units (FPUs), reported experiments in the field and experiments in literature. Experimental testing (both field tests and laboratory tests) of individual wire strands and complete wire rope constructions were carried out at a number of locations with varying environmental conditions. These data were then analysed to derive a phenomenological model that represents the observed behaviour of both ropes and individual wire layers.

Amongst the key findings of the SCORCH JIP investigation was that the corrosion endurance of steel wire rope mooring lines is largely driven by the longevity of the galvanizing or other galvanic protecting coating, and the blocking compound, which forestall the direct corrosion loss of metallic area of the relatively small steel wires. Two major mechanisms by which zinc oxidation occurs and the major environmental contributors to the acceleration of wire degradation were identified; and efficacy of various rope protection methods were assessed. A predictive model was derived which characterised the rate of zinc dissolution, performance of blocking compound and corrosion rates for different exposure and working conditions.

The outcome of the wire rope component of the SCORCH JIP was a significant advancement in industry knowledge on the corrosion behaviour of steel mooring wire ropes.
Digitalisation – The Next Frontier for the Offshore Industry
Authors: Dekker Martijn , Thakkar Anosh
Published: April 2018

The offshore industry has always been at the vanguard of technical innovation and this is not about to change. The next wave of technology will not come, however, from new ways to bend the physical world to our will with steel and human power but from bits and bytes through digitalisation.

Digitalisation is not new to our industry. Now the technology is cheaper and faster and the amount of data and level of connectivity are increasing exponentially, the application of digital technologies can deliver at an affordable cost. The energy industry is emerging from a lower-price environment in better shape and with more resilience and an increased focus on capital efficiency, cost performance and safety. The industry is also ready for a digital transformation that offers a big, if not the biggest yet, opportunity to improve efficiency in our existing operations even further.

This transformative potential has been recognized for some years. What has been missing is a comprehensive approach for applying digital technologies successfully at scale in the oil and gas industry. This reflects one of the significant differences with previous waves of innovation: most of the benefit for existing businesses will come from replication and rapid improvement cycles of across many assets and projects. In addition, digitalisation also opens up the opportunity for new business models that could change the entire industry structure.

This paper explores an approach to digitalisation that draws on successful use cases that have already realized significant value in Shell's operations. It identifies the underlying principles of the digitalisation strategy, including data strategy, approach to insourcing versus outsourcing and methodology of scaling up. The required success factors that underpin digitalisation are also explored: capability building for both people and IT/data systems; how to organize the digital deployment; and the required leadership, culture and way of working attributes. Practical examples and insights from Shell's digitalisation journey will be provided.
E-Line Intervention Enables Operator to Design, Manufacture A New Customized Bit to Mill Out Isolation Valve in Record Time and Enable Early Production from Well
Authors: Tyagi Chirag , Singh Virendra , Nayak Jyoti Prakash
Published: April 2018

A well in the Panna-Mukta-Tapti Joint Venture (PMT JV) was completed using an isolation valve as the method of isolating the reservoir whilst running the completion into the well. Mechanical failure to open the valve was not anticipated as the isolation valve had a successful history in the JV with no failures in the last 10 years. However, in this well, the isolation valve failed to open. After spending multiple days attempting to open the valve and diagnosing the cause of the failure, it was concluded that the isolation valve was mechanically stuck.

Further evaluatios of solutions incorporating Coil tubing (CT) and e-line interventions concluded that standard milling operations would pose additional challenges for the well due to the design of the completion below the isolation valve. Subsequently, a unique, star shaped milling bit was designed and manufactured to enable milling of the isolation which was smaller than 2.56" SSD and landing nipple present below the isolation valve. This was required to ensure future access for interventions through the SSD and landing nipples is not compromised and milling out the coupon from the flapper isolation valve does not get stuck in the smaller ID completion profile below it.

The newly designed bit enabled milling and subsequently expanding that hole to the desired OD of 2.7" which would allow for future interventions. E-line milling was selected due to limitations in control with CT for debris generated. The total time from identification of the problem to designing, manufacturing, testing the new bit, transporting it to India and executing the solution was 45 days. The operation itself was carried out within 45 hours vs 120 hours projected with CT, leading to a significant cost saving, equivalent of 3 times daily spread rate for the rig. This unique methodology also enabled early onset of production, avoiding a delay of approxmately three month.

This was the first time this new mill bit was applied and the first time that this isolation valve had been milled out using E-line. Existing, standard bit designs were not sufficient to accomplish this solution nor were conventional approaches satisfactory in today's economic climate. This paper will present the significant benefits accomplished from the utilization of the robotic, electric-line (e-line) intervention to mill out a malfunctioning isolation valve versus the use of coiled tubing (CT).

In addition, it will use the flexibility and control features of e-line based, intervention technology towards addressing short lead time and design modification required to meet dynamic well challenges.
Malikai TLP Transport and Installation
Authors: Huffelen Rolf van , Bruin Ruben de , Wassenaar Walter
Published: April 2018

Heerema Marine Contractors (HMC) in combination with IEV Malaysia was contracted by SSPC to transport and install the Malikai TLP offshore Sabah. Malikai is Shell's second deep-water project in Malaysia. It features the country's first tension leg platform, a floating oil production facility moored to the seabed in 500 meters water depth.

This paper discusses the installation contractor's experience and lessons learned in executing the tow and installation campaign.
Application of Digital Technologies to Improve Collaboration and Support of Remote Offshore Operations
Authors: Ryan M. F. , Kourvelas C. P. , Tuttle D. C. , Nicholls S. G.
Published: April 2018

Installation of a fiber optic cable between Newfoundland and offshore installations on the Grand Banks has enabled implementation of digital technologies which can improve safety, reliability, and profitability of offshore operations. An overview of the fiber optic infrastructure and recently established Onshore Support & Control Center (OSCC) is presented along with technical, organizational, and operational considerations for its design. To date, use of the OSCC has improved operator training, allowed shifting of offshore roles to onshore, and enhanced support of and collaboration with offshore operations. In order to implement future digital technology opportunities and capture additional benefits, a digital roadmap has been developed along with associated organizational changes to manage implementation.
Operational and Safety Improvements of Applying Real-Time Analytics in a Drilling Contractor RTOC
Authors: Madaleno A. L. F. , Neto S. L. S. , dos Santos L. A. , de Oliveira C. A. L.
Published: April 2018

This paper will present how QGOG Constellation, an ultradeepwater drilling contractor, is taking advantage of its Real-Time Operation Center (RTOC) to leverage process safety and performance in six critical areas. The company applies real-time analytics to automatically identify and alert RTOC engineers of abnormal situations.

Data analysis is supported by a data collection mechanism, communicating with a real-time analytics IoT platform. It allows the integration of data generated from drilling packages and BOP, as well as basic environmental information present on units’ drilling data servers.

Operation modes are automatically detected in real time and used as primary information. Algorithms developed by the RTOC team search and raise an alert for any abnormal situation. These tools are organized in six main dimensions: well control, well barrier assessment, equipment safety operational window, drilling problems prediction, process sensor integrity, and BOP monitoring,

A flexible dashboard platform enables RTOC engineers to develop algorithms and graphics that are customized to improve monitoring accuracy and fulfill operational needs. The dashboards that come out of this development target critical operations and allow much more data to be taken into consideration, resulting in a more structured decision-making process. Examples of successfully implemented real-time logics include a comparison of BOP-selected EDS and auto-shear status with the operation mode, comparison of combined loads on a drillstring with the tubular safety envelope, an automated trip sheet which compares the theoretical displacement of a tubular with the trip tank variation, fingerprinting of pumps-off scenarios, and automatic assessment of pressure and volume. These logics turn data into useful information and detect abnormal situations faster, taking into account much more data than a drilling crew could.

Alarms are associated with the scenarios and alert RTOC engineers of any abnormality. After verification, the RTOC communicates the rig and further actions depend on type and severity of the recognized situation.

The RTOC role within a drilling contractor is a new factor. This paper also introduces a methodology where a platform can integrate and synchronize data coming from different data sources, including third party companies and the well operator.
An Electro-Mechanical Actuator with Hydrostatic Drive for Subsea Trees to Reduce CAPEX and OPEX with Higher Reliability and Safety Levels
Authors: Orth Alexandre , Hendrix Gottfried
Published: April 2018

Although subsea production is already a mature technology, a high engineering effort is currently needed to "industrialize" the applied systems for cost optimization. The drive system applied for the actuation of subsea valves in trees and manifolds reflects exactly this challenge: how to reduce manufacturing costs by increasing safety and availability?

The first approach was based on hydraulic cylinders, which were operated by electric-piloted hydraulic subsea valves with topside Hydraulic Power Units. This system is very robust, but leads to very cost-intensive umbilicals to provide the needed fluid power and prevent environmental damages due to leakage of hydraulic fluid into the sea.

To reduce environmental pollution, complexity and costs; all-electric solutions were developed. However, hydraulic actuators continue to be used because of important benefits such as high power-density, lower friction and integration of a mechanical override.

Is it possible to create a hybrid solution which can combine the benefits of both technologies? In other industries, this dilemma was solved by integrating the hydraulic cylinder into a self-contained electro-hydraulic servo axis, which applies pumps driven by variable-speed motors for accurate positioning.

This paper presents the results of the development of an electro-mechanical actuator with hydrostatic drive to operate gate valves of subsea trees and manifolds.

The main achievements, demonstrated by simulation and testing using a 2″ valve actuator at 3,000 m water depth, are: Cost-effective modular design using industrial componentsEnvironmentally friendly set upLower power consumptionHigh availability and condition monitoringFunctional safety able to achieve SIL 3Integration of mechanical overrideAdvanced Electric Controls with Industry 4.0 connectivity

This system is an important step to close the technology gap to accomplish the all-subsea factory. Especially, it can be applied in cases where the hydraulic actuators are still preferred instead of all-electric actuators.
2014-2017 Anomalous Loop Current Activity
Authors: Sharma Neha , Storie Jill , Ivanov Leonid , Magnell Bruce , Leber Michael , Gustafson Drew , Zimmerle Heather
Published: April 2018

The years 2014-2017 marked a period of anomalous and extreme Loop Current (LC) activity that resulted in significant impact on offshore operations for the first 18 months, followed by a 4- to 6-month period of more typical behavior and then 15 months of uncharacteristic inactivity. The objectives of this study are to (i) provide a detailed description of the kinematic structure of the Loop Current Eddies (LCEs) observed during this time frame; (ii) determine the vertical extent of each eddy and the effect of eddy activity on near-bottom currents, and (iii) establish a relationship (if any) between eddy activity and intensity of inertial oscillations within the water column. We present data collected from ADCPs at several locations in the northern Gulf of Mexico along with an extensive network of drifting buoys in correlation with daily frontal analyses and a comparison with historical events. To estimate the intensity of inertial oscillation and its variability in time, we computed rotary current spectra for periods characterized by high and low eddy activity. While circulation patterns during early 2014 were fairly typical, an apparent sudden increase in energy marked the beginning of hyperactivity in late June. Eddies Lazarus, Michael, Nautilus, and Olympus spun off the LC, each eddy experiencing multiple reconnections with the LC before its final separation in addition to amplified intensities (over 3 knots, max 4.5+ knots). December 2015 marked the beginning of the second phase. Another eddy (Poseidon) separated from the LC in April 2016; however, the winding down process of the LC circulation was already in effect. Poseidon did not exhibit a significant northward migration and the LC itself remained far south. In the central Gulf, the passage of Poseidon was followed by the passage of a subsurface cyclonic eddy, without a significant surface expression, propagating westward. For the next 18 months, the LC remained extremely inactive. While currents in the near-bottom layer were not directly correlated with the flows in the upper part of the water column during the period of the high eddy activity, the later period was characterized by more energetic near-bottom flows, suggesting LCE’s may stimulate generation of topographic Rossby waves that cause strong near-bottom intensities. No significant correlation between the presence of LCE’s and intensity of inertial oscillations was found. Results of recent near-surface and water column current observations are presented in the paper.
Sustainable Offshore Wind Energy: Faster and Larger at Lower Cost and Less Environmental Impact
Authors: Dirks W. G , Kappen J. M. J. , Scheltens R. D. , Winkes J. , Wochner M. S.
Published: April 2018

Objective

"The offshore wind industry is in the process of becoming an advanced and mature industry in North Western Europe, with the costs of the energy produced by offshore wind farms rapidly decreasing. The cost of offshore wind energy, however, is still higher than the cost of energy from fossil sources. The success of offshore wind, as a significant contributor to the global energy supply in the future, will depend on future energy prices, enabling legislation to further develop offshore wind and technologies that reduce CAPEX and OPEX costs. This paper will present an overview of technologies that are being developed by Van Oord and other innovative companies in the offshore wind supply chain, notably AdBm from the USA and Fistuca from the Netherlands.

The presented technology developments aim at lowering the costs of foundations for offshore wind turbines, which is a significant part of the total CAPEX cost. The costs of foundations can be reduced by: 1) optimizing the design; this means less weight, easier to install and with the lowest possible maintenance costs over its lifetime, 2) developing installation vessels and equipment that enable faster installation with limited dependency on sea state. At the same time, wind turbine manufacturers are developing larger offshore wind turbines and legislators are instituting more limitations, for example on the emissions of underwater noise. These developments create additional challenges for upscaling the installation capacity and performance of vessels and pile driving equipment and the development of technology that reduces or abates underwater noise.

This paper presents an overview of new technologies related to foundation design, installation vessels, pile driving technology and noise mitigation systems and the challenges to get those new technologies ready for implementation as fast as possible.

These new technologies will become relevant for upcoming sector developments, e.g. in North America and Asia, with specific local challenges like difficult soil conditions, restricted installation periods due to weather constraints, or noise mitigation to prevent damage of sensitive marine life.
Malikai TLP: Collaboration in Design and Delivery of the Malikai SCCTTR
Authors: Aramanadka Shankar Bhat , Hafernik Steven , Power Thomas , Tay Kay Yang
Published: April 2018

Floating vessels with dry tree production equipment are large capital expenditure projects with multiple interfaces often spanning several entities, including the Operator, Engineering Procurement and Integration Contractor (EPIC), Rig Builder, Production and Drilling Top-Tensioned Riser (TTR) supplier, Subsea Wellhead supplier, and Surface Wellhead/Tree supplier. Design and Interface Management play a significant role in the success of a project of this magnitude. The Shell Malikai Single Combo Casing Top Tensioned Riser (SCCTTR) was successfully deployed and commissioned on the first TLP in Malaysia. The Malikai SCCTTR is an industry first and an example of innovative design configuration coupled with rigorous project execution to deliver a system that is an enabling technology for current industry market conditions.

The SCCTTR is a single riser used first for drilling and then remains in place for the full field life. This provides significant cost savings, both in hardware and operational time for large field developments, but introduces technical challenges to meet the requirements of both traditional drilling and production/water injection risers. This paper presents key design challenges to meet the requirements for ‘multi-purpose’ configuration and identifies how they were addressed to accomplish the project goal of flawless delivery. Project management was a key factor in achieving this goal. Shell chose a one-stop solution for delivery of the subsea wellhead and SCCTTR which provided advantages in management of interfaces and overall delivery. While this minimized interfaces, it still required a significant effort to coordinate components from multiple continents to deliver a single system. In addition to project management, the system required innovative design, as illustrated by the tensioner system, which introduced new features such as deflection absorbing bearing pads to limit the impact of the SCCTTR on the TLP hull design. Even with the additional features, the new tensioner system was designed, manufactured, and qualified within the project schedule. The Malikai SCCTTR stands as a testament to what can be accomplished when innovative design approach is coupled with robust project management and collaborative efforts between operator and equipment suppliers.
All-Electric Subsea Systems - Intelligence on Demand
Authors: Elgsaas Kristin Moe , Hjertvikrem Terje , Hua Wei , Tryti Svein , Glomsaker Terje
Published: April 2018

Interest in All-Electric subsea solutions has grown significantly over the last few years. The trend coincides with subsea electric actuation gaining a solid track record after 15+ years of operational experience, and ongoing industry wide discussions and validation of the benefits of All-Electric systems. A diverse group of subsea vendors and operators, including BHGE, has shared analyses showing how a move to All-Electric subsea production system reduces CAPEX and OPEX.

This paper starts with an initial introduction to All-Electric subsea systems, including system types, and an overview of the direct benefits of moving from electro-hydraulic to fully electric solutions. However, the main focus of the paper is the additional benefits from subsea electrification that can be derived by leveraging the data available in electric systems to confirm system health at any given time and predict future system conditions. Benefits are considered in the context of electrically actuated systems, life of field production system performance and enterprise level strategies. Finally, the paper looks at how any electrification strategy should be aligned with automation efforts and digital strategies.
Autonomous Inflow Control for Reduced Water Cut and/or Gas Oil Ratio
Authors: Elverhøy Anita B. , Aakre Haavard , Mathiesen Vidar
Published: April 2018

One of the main challenges for increased oil recovery is major breakthrough of unwanted fluids as water and gas, due to uneven influx along the horizontal section. The problem can be avoided or significantly reduced by deploying novel inflow control technologies. Inflow Control Devices (ICD) and Autonomous Inflow Control Devices (AICD) are able to delay breakthrough, but not stop the production of unwanted fluids completely. The newest generation of inflow control technology, the Autonomous Inflow Control Valves (AICV) can optimize the oil production, in both new and old wells, and reduce water cut and/or gas oil ratio significantly. The benefit of the AICV is to provide balanced inflow of oil along a horizontal well, by autonomously choke or close the breakthrough compartments, and still produce from the rest of the reservoir.

The commercial near-well simulation tool, NETool, is used to model a horizontal section with uneven influx along the well. Completion with 16 evenly distributed AICVs in 8 isolated zones is compared to an open hole situation and completion with nozzle ICDs. Simulation of one medium viscosity oil reservoir with water choking, and one light oil reservoir with gas shut-off are performed to demonstrate the increased oil production and recovery by implementing AICV technology. In NETool several models of different types of inflow control are available, including the model of Statoil's Rate Controlled Production (RCP). In this study, the RCP function is tuned to fit the experimentally determined flow performance behavior of the AICV and the function is utilized in the applied simulation.

A good correlation of the experimentally flow performance curves and the flow performance behavior of the tuned RCP function is obtained. The tuned RCP function gives a realistic assumption of the functionality of the AICV, and shows that the potential of increased oil production and recovery is significantly in a range of reservoirs. The simulation result shows that for the medium oil reservoir the water cut (WC) is decreased from 60% with use of open hole completion to 29% for the situation with AICVs installed. The well completed with AICVs increase the oil production with 75%. In the light oil reservoir, the AICV closes the gas breakthrough compartments completely, and increases the oil production from the other zones. The Gas Oil Ratio (GOR) is dramatically reduced from 1281 Sm3/Sm3 for the open hole situation, to 57 Sm3/Sm3 with AICV completion. In both cases a simulation of a nozzle ICD is performed, showing that the performance of the ICD is in between the open hole completion and the situation with AICVs installed.
Mooring Design and Operation Practice for Floating Units Subject to Ice Loading
Authors: Morandi Alberto , Kwan Chi-Tat Thomas , Shelton John , Yao Aifeng
Published: April 2018

An Arctic Mooring JIP was initiated by Kwan Engineering Services and Global Maritime in 2013 to address the issue of Arctic mooring design and operation practice, which was completed in 2016. There were 24 participants including operators, drilling contractors, regulators, designers, and hardware manufacturers with a total funding of $780k. The JIP had five tasks related to mooring in the Arctic:Task 1 – Guidance on mooring strength design practiceTask 2 - Assessment of disconnect devices and requirementsTask 3 - Assessment of mooring components for operations in the ArcticTask 4 – Guidance on methods for ice load predictionTask 5 - Guidance on ice management strategies

A guidance summary on Arctic mooring design and operation practice was developed by the JIP for input to industry standards. This paper presents the key elements in the guidance summary.

ISO 19906 ‘Arctic Offshore Structures’ (ISO 2010) is the most recognized Arctic design code for fixed and floating structures, which does not provide practical guidance for mooring design and operation. API RP 2SK (API 2005) is the most recognized mooring design code, which does not cover moorings subjected to ice loading. The guidance developed by the Arctic Mooring JIP bridges the gap between these two codes and is a significant milestone for the design and operation of Arctic floating systems. The API Mooring Resources Group has incorporated the guidance summary developed by this JIP into a draft document for the 4th edition of API RP 2SK.
Moving Ahead in Campos Basin: Integrated Strategies in the Implementation of Complementary Projects
Authors: de Oliveira M. I. R. , Apoluceno D. de M. , Brum R. P. , de Melo P. A. L. S. , Neto L. de A. Henriques , Nogueira P. de B. , de Oliveira R. P. , Nunes F. P. , Pelisoli L. O. , Silva L. dos S. , da Silva R. M. P. , Soares G. F. , Testi L. B.
Published: April 2018

Petrobras launched the PDBC (Campos Basin Development Plan) as part of Company’s Strategic Plan to increase production and incorporate reserves in a scenario of mature fields and low oil prices. The plan is based on an integrated analysis of opportunities, combining skills of professionals with different backgrounds, allowing cost reduction and the deployment of technical solutions. It also has defined short- and long-term actions to achieve these goals. In the short-term horizon, actions included campaigns to remove damage of producer and injector wells, improvements in artificial lift methods, reduction of time required for projects approval, early drilling of wildcats, improvements in the efficiency of water injection, among others. In the long term, Petrobras performed a critical analysis of the recovery factor for each reservoir, identifying bottlenecks and evaluating technological solutions with multidisciplinary teams. Results indicate a significant increase in production in 2017 and the proposal of new projects in these fields. This paper presents the methodology used in the program and the results obtained so far for the giant oil fields of Roncador, Marlim Sul, Marlim Leste, Barracuda, Caratinga and Albacora Leste, responsible for approximately 20% of all Brazilian production. It also presents the future applications in fields where reduction of costs and technical solutions can contribute to increase production and reserves.
Flexible Hose Technology Benefits for Ship-to-Shore High Pressure Natural Gas Transfer
Authors: Szekely Gergely , Peixoto Eduardo
Published: April 2018

A few years ago the industry started to look for alternatives to the LNG loading arms and moved towards the cryogenic hoses. Recently the volatile gas prices and the consequent quick paced projects resulted the same pattern on the high pressure side of the FSRU: more and more players are looking into utilizing high pressure flexible hoses for the ship-to-shore regasified transfer lines due to the technology's inherent advantages including its very short lead time.

This paper is to demonstrate the benefits of the flexible hose transfer lines over rigid marine loading arms when used on the high pressure side of an FSRU or even an FLNG vessel. A side-by-side comparison of the two technologies is presented accounting for technical capabilities, installation considerations, associated levels of risks as well as investment costs including upfront expenditure, operational and logistics costs. The operational envelope of the hose transfer line is studied and defined by finite element analysis (FEA).

Brief overview is given on the existing operational history of high pressure flexible hoses on FSRU vessels. Technical properties of the hose technology are discussed in details in contrast to marine loading arms, such as the magnitude of weight and footprint reduction, fewer number of leak paths along the transfer line and much lower requirement of hydraulic power to operate. The loading arm's moving components are substituted by the flexible hose's intrinsic flexibility significantly reducing maintenance needs and downtime. It is highlighted how the lack of complexity of the system drives down the costs: starting with a significantly lower CAPEX through reductions in OPEX as well as savings on installation and logistics. It was found that the complete lead time of less than 6 months of the whole system can address such quick paced terminal projects which was not possible with marine loading arms. Finally the result of the system integration study will be presented supported by the operational envelope limits derived from a FEA model.
An Underwater Robotics Platform for Hybrid AUV/ROV Systems
Authors: Siesjoe Jan
Published: April 2018

Modern ROV and AUVs are becoming more and more capable. Traditional ROVs are enhanced by sophisticated piloting aides to improve quality and to reduce operator load, minimizing errors and increase safety. Increasingly more complex AUV operations are becoming possible which involve decision making and intervention. In many ways the line between advanced ROV and AUV is disappearing.

These systems are also becoming more and more complex and therefore more expensive to develop and qualify. At the same time the demands and tasks are changing requiring vehicles of different shapes, power levels, tools and functions to cope with these.

The way that has chosen to address this, to be able to quickly field new vehicles that meet customer demands in a cost effective manner, is a technology platform. Reusing hardware and software components in between ROV and AUV systems allows us to build new systems that from the start have proven performance, reliability and a large user base to build on. This, combined with open interfaces that allow customers and third party suppliers to provide their own "intelligent" functions into the system, allows rapid deployment of new systems such as resident AUV and ROV systems.

This paper will present the Robotics Platform and interface philosophy along with a view of the roadmap forward. It will cover existing components and how they are used. It will discuss open interfaces and how they are used in recent projects and some views on coming developments.