bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbon Footprint Minimization for Deepwater Pipelay Construction
Authors: Young Raymond , Kashani Manou 
Published: August 2021

Abstract
With recent oil and gas discoveries in deepwater offshore, these regions have become the hotspots for oil and gas exploration. It is for this reason that major pipelay contractors are developing more advanced construction vessels with high lay tension capacity, payload and high specification dynamic positioning (DP) systems to operate at even deeper water depths. It is shown that at water depths of greater than 1000 m, one of the major construction costs is fuel consumption, which is directly related to the level of thrust and hold back tension the laybarge is required to maintain during pipelay operations. Furthermore, the fuel consumption and the resulting carbon footprint, is shown to increase disproportionally as the laybarge thrust increases at deeper water depths. For example, a deepwater laybarge (DP3 class) with a typical operating power of 40MWe can consume 130 metric tonnes of diesel fuel per day (1.5 kg/s) with carbon dioxide equivalent emissions (CO2e) of 3,200 kg per tonne of fuel. This is a substantial measure of emissions, typical of a pipelay vessel during pipe lay operations. It is for this reason that American and European air pollutant emission inventory guidelines expect environmental impact documents for all marine activities, including construction, to be calculated and submitted to relevant environmental protection agencies. By comparison, a typical car will produce around 4,600 kg of CO2e per year.
Currently, deepwater pipeline engineering and design is based on relevant offshore design codes and standards, e.g. DNV-GL and API. Within the framework of those codes and standards, a design approach is presented within this paper that shows that, by properly combining pipe strength and stiffness characteristics with pipelay construction loads, a unique bending strain limit can be defined that would lead to the most economical solution that minimizes the vessel thrust and thereby radically reduce fuel consumption and associated CO2e emissions during pipelay activities.
This unique design approach would be of interest to operators, pipe manufacturers as well as the pipelay contractors. Because of the construction economy and the minimizing of the carbon footprint, this approach is an attractive design method to all concerned parties, including environmental protection agencies. Since the design approach promotes higher steel grades, it would be very much in the interest of pipe mills to further develop and elevate the use of higher steel grades higher than the present widely used API 5L, X-65. Pipelay contractors will benefit by installing pipe with lower levels of thruster power, resulting in safer and a more reliable station keeping and, most significantly, a lower fuel consumption.
Condition Monitoring of Next Generation Digitized Electric Subsea Actuators
Authors: Winter Tobias , Glaser Markus 
Published: August 2021

AbstractA detailed knowledge about the health status of the installed assets is the key for continuous production without unexpected events and downtime, which causes production loss. A major aspect is the prediction of the occurrence of a failure before the affected function is demanded. This is one purpose of the Condition Monitoring (CM), Prognostics and Health Management (PHM) and the application of a Digital Twin. The paper presents the result of an ability analysis for a subsea actuator towards its possibilities to increase the availability through a novel and extensive grade of information. The paper presents the resulting architecture and solution to achieve an actuator design, which is capable to provide a high safety, high reliability and a predictive health management which is prepared for a digital twin application. For this purpose, an applied Condition Monitoring concept is described and shown based on the case study.The analysis and resulting solution is based on a detailed research towards the state of the art. Different available subsea actuators are analyzed towards the communication interfaces and the ability to allow CM. Therefore, the required status and information of the actuator are shown (e.g. Torque, position, temperature, acceleration, water concentration in oil, humidity, pressure, inclinometer). The required environment information about the actuator are evaluated with the help of a failure mode analysis. The different sensor principles provide the necessary information. The paper evaluates the significance of the sensor information towards the CM concept. The data can be provided on different communication interfaces and protocols. These are analyzed towards the satisfaction of the CM requirements.The result of the analysis is a detailed architecture of a CM capable subsea electric actuator including the CM concept. The possible interfaces are shown and the provided sensor data by the actuator. The sensors provide the input for the CM model and the remote accessibility and controllability of the actuator.The result is the novel design of a subsea actuator, which fits perfect in a digitalized subsea environment to increase the availability and controllability including a CM concept.
Longer Tiebacks by Electrification and Remote Power
Authors: Verdeil Julien , Manach Julien 
Published: August 2021

Abstract
Standard field architecture is generally based on topsides production and distribution of power and chemicals necessary to operate equipment in drill centers. The paper will present efficient field architectures adapted to operate remote tie-backs with different combinations of subsea electrical power distribution, remote power generation and storage, and improved ways to mitigate corrosion, hydrates and wax issues for long tie-backs.
Developing remote resources requires several technology bricks that enable a cost effective and reliable technical solution. To reduce the CAPEX, the main objective is to reduce the number of tubes typically with one single heated flowline to avoid a long and costly service line or with one small power cable and local distribution of power to avoid a heavy and expensive large umbilical. Alternatively, power can be generated and stored at drill center location and chemicals can also be managed locally with limited OPEX.
A significant focus was done recently on technology developments enabling long distance tie-back developments. Domain of application and interest of each technology is generally well known and the delivered value is well presented. Looking for the most appropriate combination of technologies on a new field development is now the new challenge to figure out new opportunities. This paper proposes to group the long distance tie-backs fields in three main categories based on extensive studies done for several operators and to present the best architecture for each category. The first category groups very long distance single end tie-backs for which a cold flow system combined with full electrical equipment at drill center location is adapted. The second one is applicable for more consequent development where several drill centers are combined to one long and heated export line; with subsea electrical distribution to power each branch of the remote field and local management of chemicals at each drill center. The third category groups all daisy chain developments for which a heated line gathers the production coming from each fully electrical drill center.
Each field development can generally be categorized in one out of the three categories presented in this paper. Based on this categorization, the right combination of low carbon and reliable new technologies enables valuable development of long tie-backs and then increases utilization area of each existing asset.
Novel Elastomer Materials for Extreme Temperature Operation in Subsea Thermal Insulation Applications at Unlimited Water Depth
Authors: Jackson Adam , Diaz Rodrigo , Svalund Heidi , Hansen Raymond , Hartviksen Grethe 
Published: August 2021

Abstract
Rubber based systems have been used in subsea thermal insulation for many years and have proven themselves to be reliable and cost efficient. Formulations have been changed over the years, pressing the maximum usage temperature upwards and into the realm of 160 to180°C in a hot-wet environment. Until recently there was a need for high temperature along with pressure vessels (autoclaves) for vulcanisation. This has limited the widespread use of such systems. Recent changes have eliminated the need for autoclaves, however the high temperature vulcanisation hasstill been required.
A novel formulation has been developed to address these shortcomings, so that this class of materials could have wider use. This new material employs freely available materials in a unique blend. The material contains no hydrolysable groups and can operate from −40°C to 180°C continuously in air and in a hot-wet environment and retains its resilience and flexibility; and thus opening for use in both high and low temperature systems. The formulation does not include the use of hollow glass microspheres and is, correspondingly, without water depth limitations. A new, highly reliable vulcanisation chemistry allows for a stable latency time for application, with vulcanisation temperatures reduced to 50°C. This allows for rapid hand application and simultaneous vulcanisation on subsea trees, valves, manifolds, etc. The material is self-agglomerating, merging under gentle pressure, and can be applied at high thickness. As the base material has an intrinsically low thermal conductivity, glass-based fillers are not needed. The material adheres well to painted or primed surfaces and to many other materials typically used in the offshore thermal insulation industry.
The 2-component material is conveniently combined on site, reducing the need for refrigeration during transport and easing mobilisation logistics and is applied using simple hand tools. Extruded profiles can be used directly on complex structures or combined into sheets for ease of application on more regular shapes in order to optimise application rates. Moulds are not required for application, reducing engineering and fabrication cost, while also shortening mobilisation time.
The system has been extensively qualified according to ISO 12736 for continuous use at 180°C. This paper will detail important aspects of the development project along with the results of the qualification testing.
Offshore Urban Extension of the Anse Du Portier In Monaco
Authors: Aristaghes Pierre , Compte David 
Published: August 2021

Abstract
As part of the Monaco offshore urban extension project, Bouygues TP is in charge of design & build a maritime infrastructure as the first step of the six-hectare expansion of the city into the sea. This maritime infrastructure consists of a fill enclosed by a band of trapezoid concrete caissons and will serve as base for construction of the new residential area.
The paper focuses on some of the problems which had to be solved:
optimization of promenade level and wave absorbing chambers in conjunction with minimal reflection and safety related to overtopping, accounting for sea level rise and correlation between extreme waves and water levels. caissons and rubble mound foundation stability related to waves and seism, including extra seismic forces due to buildings considering the high reclamation height and the immediate proximity of building foundations. the way in which caissons representing nearly 80,000 m3 of concrete can be built in a floating and continuous manner via a caisson box (or "caissonnier" in French), within a particularly short time frame presence of a small craft harbor with shops along the quays, whose location was fixed for urbanistic reasons, which requested optimizations in detail of anti-overtopping devices as much as possible integrated in the urban context, need to convert a breakwater caisson into a low crested swimming pool caisson, with plexiglas windows exposed to wave slamming from outside, but also from inside due to overtopping impacts over the swimming pool basin. Ecodesign has been closely associated with hydrodynamic and coastal engineering, based on estimation of wave pressures and induced velocities in the different possible locations (chambers, walls, structures toes …). The eco-friendly development strategy is based on the wide-scale deployment of a range of 11 solutions which will be described (potential for caissons to be colonized, nursery function development, etc…). Moreover, posidonia transplantation has been done via concrete open boxes, whose stability under storm waves has requested CFD calculations to model local velocities and optimize their shape.
Challenges of Engineering the Hottest Subsea Heated Pipeline for the CRISP Project
Authors: Geertsen Christian , Langford Steve , McKinnon Colin , McKinnon Fred , Niesen Vicki , Orberg Frederico , Wang Nick 
Published: August 2021

Objectives/Scope
The project was a 2km, electrically heat-traced, subsea pipe-in-pipe (PIP) system for transportation of a bitumen-like material across a shipping channel. Due to the viscosity of the bitumen, it must be transported at a minimum of 160°C; has a normal pipeline operating temperature of 200°C; and a design temperature is 228°C.

Methods, Procedures, Process
Due to the high operating temperature, pre-stressing and backfilling the PIP was required to lock in stresses at an intermediate pre-stressing temperature. The electrical heat-trace wires (installed to heat up the inner pipe and prevent setting of the bitumen during cooldowns) were used to achieve this pre-stressing during the fabrication process. The heating schedule causes high stress levels and require advanced engineering analyses to model the behaviour of the inner and outer pipe during the fabrication, installation, pre-stressing, and operation. The complex loading history of the inner pipe and the expansion spools was included in the global 3D, finite element (FE) models that were used to validate the pipeline profile, backfilling, pre-stressing temperature, and sequence of operations.

Results, Observations, Conclusions
The complex buckling behaviour of the inner pipe is presented and shown to be within DNV GL OS-F- 101 code limits. The end expansion during the various stages of pre-stressing is presented and compared to observed behaviour. The loads and stresses in the bulkheads are presented and shown to be acceptable. The analysis demonstrates that the pipeline system can be safely installed and operated up to the maximum design temperature of 228°C.

Novel/Additive Information
The project used pre-stressing by heating the inner pipe to an intermediate temperature before coupling the inner pipe to the outer pipe. The purpose of the pre-stressing was to manage the high axial stresses making it feasible to achieve the high design temperature of 228°C. Pre-expanding of the expansion spools at either end of the subsea pipelines was also used due to the space limitations. Innovative engineering analysis and construction methods were used to ensure the integrity of the inner pipe during the pre-stressing process and operation.
A New Era: Large Subsea Multiphase Compressor - Driven by Subsea Adjustable Speed Drive
Authors: Lendenmann Heinz , Fløisand John Olav , Vatland Svein 
Published: August 2021

AbstractThe use of subsea processing equipment, which maintains, increases, and accelerates oil and gas production, is now more and more widespread in offshore subsea field developments. Furthermore, there is a strong drive for electrification of offshore fields, both subsea and topside, to lower emissions. To meet the technical challenges, a significant effort is put into research and technology development by academia and the industry. ABB, a specialist in electrical equipment and control systems, and OneSubsea, a specialist in subsea processing, have executed large development programs organized as Joint Industry Projects (JIPs) together with oil and gas operators. In this paper, we discuss how ABB and OneSubsea joined forces in testing and validating their respective subsea technologies as a full subsea system for subsea multiphase gas compression.This paper presents the world's first full-scale, combined subsea adjustable speed drive (ASD) and multiphase compressor (WGC6000) string test. In spring of 2020, both the ASD, and the WGC6000 reached Technology Readiness Level 4. The string test, with both units concurrently submerged, completed its witness test program in June 2020, with mapping of the WGC6000 speed and power envelope and a subsequent 24 h thermal stability run. The flawless test result confirms the strategic development road map for all the involved partners.The technologies presented in this paper are now fully qualified and available for commercial use enabling a paradigm shift in subsea oil and gas production.
Vertical to Horizontal - Ultra Deep Azimuthal Resistivity Tool UDAR Service Helping to Maximize Production
Authors: El Sedeq Ahmed Zarroug , Hughes Neal , Oian Tore , Byrski Piotr , Denichou Jean-Michel , Nketah Daniel Ndubuisi , Dahroug Mohamed Saher 
Published: August 2021

Abstract
Dvalin field, discovered in 2010-2012. The location of this field is in the Norwegian Sea, as shown in (Figure 1). Dvalin field is an HPHT gas field in Middle Jurassic sandstone in the Garn and Ile Formations – the former being homogeneous with better reservoir properties, during the later heterogenous with low quality. (DVALIN, 2020)
The well 6507/7-Z-2 H objective is to produce hydrocarbons from the Jurassic reservoir section of the Dvalin field safely and cost-effectively. The well was planned to be drilled near vertical in the reservoir section and TD'ed at a maximum depth corresponding to the Garn Formation base.
After the productivity results from Z-3-H well came in at the low end of expectations, it was evaluated and decided to change the well profile of the Z-2-H well from vertical reservoir penetration to a horizontal profile; to have two penetrations with a minimum of 150m MD separation in the upper high permeable streak and then drop to penetrate lower high permeable streak. This decision was conducted only three days before starting the 17.5-inch section on the subject well. One Team culture was the key to achieving this significant change successfully.
The decision to change the well-profile was conducted after a thorough engineering evaluation, including offset well analysis, which was very limited as the closest horizontal well was more than 40 km away.
As the well was not planned as a horizontal well, departure between the surface location and Target Easting & Northing was minimal. Therefore, a high turn and deeper inclination build were required, which added some complexity to the well design.
One of the additional primary risks related to this change of trajectory design is deploying a more complex BHA design in the reservoir section with a full suite of LWD technologies run in an HT environment. In the planning phase, special consideration was needed to accurately simulate the expected circulating temperature and have proper procedures in place for temperature management and control.
Being the first horizontal well in the field, thus detailed planning was key for successful execution. Ultra-Deep Azimuthal Resistivity Tool (UDAR) Reservoir-Mapping capability was considered to help optimize the landing and navigate within the reservoir section. A feasibility study was conducted, and a 2-receiver Ultra Deep Azimuthal Resistivity Tool BHA configuration was selected and deployed.
During the execution, the Ultra Deep Azimuthal Resistivity Tool real-time inversion mapped the reservoir geometry, revealing resistive layers within the Garn formation, thereby facilitating optimal placement of the well to achieve the set objectives.
The well execution was largely considered flawless, with the real-time Ultra Deep Azimuthal Resistivity Tool data and corresponding interpretations facilitating decisions.
Riser Robotic Inspection - Reducing Safety Risk While Improving Efficiency and Effectiveness
Authors: Mabile Nere’ Joseph , Vagata Alessandro 
Published: August 2021

Abstract
Integrity management is an ongoing lifecycle process for ensuring safe operation and fitness for service of offshore oil and gas production systems, including risers. Risers offer a means of transporting fluids between subsea wells and the host platform crossing the splash zone that is probably the most critical region for corrosion and exposure to external damages. Furthermore, with their proximity to the personnel on the platform and to the topside equipment, risers are considered safety critical, and are therefore, subject to planned inspections followed by an engineering assessment of the findings. This paper discusses the motivation and business driver for developing and implementing a new and cost effective risers’ inspection methodology in the splash zone based on innovative robotic platforms. The technical features and the capabilities of the robot are outlined.
Traditionally, risers’ inspections are carried out by rope access technicians and divers or ROV below the water line using conventional technologies as spot ultrasonic thickness measurements, traditional radiography and visual assessment. This type of inspection is based on a first visual assessment followed by NDE testing only if some finding is spotted. Internal defects or defect under coating, e.g. splashtron, can be easily overlooked, compromising the entire assessment process. Additionally such activities are often limited by accessibility, weather, and Personnel On-Board (POB) accommodations, but primarily they involve risks to inspector's safety.
Backbone of the presented methodology is the use of a robotic crawler that has the key advantage to inspect autonomously the risers, navigating over obstacles like clamps and supports. The robot can carry a variety of payloads for visual inspections, surface profiling, and NDE examinations with the ability to scan large surfaces with or without coating and detect internal and external defects. It can operate in the topside, splash zone and subsea sections of the riser. The inspection data are processed in real time for an immediate assessment of the integrity of the asset.
Examples are presented and comparison is made between traditional inspection methodologies and robotic autonomous methodologies to demonstrate the improvement of inspection effectiveness and efficiency.
The paper also discusses the potential areas of future development, which include Artificial Intelligence (AI) algorithms to further automatize the process and methodologies of risers’ inspection and data analysis.
A New Fundamental Understanding of Gas in the Drilling Riser
Authors: Leach Colin , Zhou Guangzhao , Denduluri Veerabhadra , Wong George , Krishnamoorti Ramanan , Prosperetti Andrea 
Published: August 2021

Abstract
The work described here originated from the tragic and ultimately environmentally catastrophic event at the Macondo well in April 2010. The first part of the paper addresses the causes for the sudden and often destructive ejection of hydrocarbons from a riser when a gas kick escapes timely detection. The approach differs from previous work on the subject and provides a realistic understanding of the sequence of events responsible for the phenomenon. The focus is on the crucial few minutes and seconds prior to the sudden eruption of gas and provides a quantitative illustration of the extreme rapidity of the ejection which leaves no time for a drill crew to adopt mitigation measures. It is shown that, in many cases, a back-pressure applied at the top of the well can be beneficial. The second part of the paper describes a novel method for the detection of gas which relies on the measurement of pressure differences along sections of the riser. These data are sensitive to the mean density of the fluid in the section and can therefore detect the presence of free gas. Laboratory experiments supporting the idea are described. Proper signal processing can be developed which may be able to allow for automatic mitigation measures to be taken in the event of an otherwise undetected gas influx approaching the surface.