bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testing In-Well Dual Canned ESP Completion System to Validate Safe Deployment in Deep Water: A Collaborative Effort to Understand Surface and Downhole Requirements
Authors: Tijerina Kim , Pardo Carlos , Hope Andy 
Published: April 2015

Abstract
Deepwater and ultradeepwater completions employ numerous hydraulic control lines for operating downhole equipment as the primary method of actuation or as back-up systems for control and actuation. Incorporating a completion system with an in-well lift, i.e., electric submersible pumps (ESPs), increases the number of electrical lines that are needed for operation. The total number of control and electrical lines maximizes the number of hydraulic and electrical lines that can be terminated back to the tubing hanger and wellhead. On surface, managing and running the numerous control lines can be daunting. Weight and size limitation and available rig floor, deck, and sub-deck space must be considered when planning placement of reeled lines, back-up systems, and preparation of supporting systems for spooler and reels.
In this paper we discuss the planning and execution of an installation test conducted in close collaboration with an operator. This stack-up test was conducted to determine whether a completion system incorporating a dual canned ESP system with multiple control lines can be efficiently and safely deployed in a deepwater, high-pressure/high-temperature (HPHT) environment.
The completion system uses numerous hydraulic control lines, tubing encapsulated conductor (TEC) lines, and ESP electrical cables to support the various downhole completion equipment systems. The control lines and cables are various sizes and shapes, further complicating their manageability. Testing was successfully performed in a 500-ft test well on a land rigand the equipment and processes used were deemed scalable to a drillship operating in deep water. Results of the test suggest that safely deploying a dual canned ESP system in a deepwater well is possible. Doing so would bring increased revenue from the additional years of production enabled by the dual canned ESPs.
Gulfstar - Structural Design of the Classic Spar Hull for Improved Constructability
Authors: Poll Philip , Park Y.C. , Converse Robin , Godfrey Dan , Gian Michael 
Published: April 2015

Abstract
Historically, Spar hulls have been compartmented using both flats and radial bulkheads. These hulls were fabricated into quarter or half sections and joined into full cylinder sections then into the full hull length while in a horizontal orientation. This approach left considerable fabrication work to be performed after assembly, disadvantageously, due to the horizontal position.
The configuration of the Gulfstar FPS reduces the number of radial bulkheads by locating the flats closer together, thus opening up the option to fabricate full cylindrical sections upright with open tops for ventilation and access during fabrication. Rotating each cylindrical section for final assembly was not required until all possible work, inside and out, on each section had been completed. This fabrication plan leaves only structural and systems tie-ins between sections once blocks are rotated and set in place.
Vertical fabrication of sections starts an overall structural arrangement philosophy to develop a configuration that is not only repetitive and efficient but also "fabrication friendly." The idea for improving constructability permeated other aspects of structural design. The purpose of this paper is to summarize some of the ways in which the Spar structure was arranged to improve fabrication and to evaluate the expected improvement with actual fabrication experience. This paper presents the genesis of the basic framing then culls out and discusses some notable lessons learned.
The information and results presented in this paper are applicable to engineers, designers and fabricators when evaluating structural arrangements and fabrication options for stiffened plate hulls, particularly Spar hulls. Cost and schedule benefits can potentially be achieved by incorporating some of the lessons learned presented in this paper.
Loads and Motions for Utility-Scale Floating Offshore Wind Turbines Supported by Semi-Submersible Platforms
Authors: Sahasakkul Watsamon , Manuel Lance , Nguyen Hieu , Sari Ali 
Published: April 2015

AbstractThis study is focused on the long-term reliability analysis of loads and motions for a utility-scale floating offshore wind turbine supported by a semi-submersible platform situated in the North Sea. The floating wind turbine, which consists of a 5-MW 3-bladed rotor, is assumed to be mounted on the OC4 semi-submersible floating platform. The platform consists of a main column, three offset columns, a cross frame, and pontoons, deployed at a site with a water depth of approximately 200 meters. A mooring system consists of three catenary lines together with the turbine and platform completes the integrated system. Based on the metocean conditions characterizing the selected turbine site, a number of sea states are identified for which coupled-dynamics simulations are carried out using the aeroelastic computer-aided engineering (CAE) tool for horizontal-axis wind turbines, FAST. Short-term turbine load and platform motion statistics are established for individual sea states that are analyzed. The long-term global performance analysis yields estimates of 50-year loads and platform motions that takes into consideration response statistics from the simulations as well as the metocean (wind-wave) data and distributions. This study seeks to assess long-term loads and motions associated with large utility-scale offshore wind turbines that might be deployed on floating platforms for planned offshore wind power development in the U.S.
Lucius Subsea Design and Installation
Authors: Dean Timothy , Haines Paul , Carlstrom Marsha 
Published: April 2015

Abstract
This paper describes the architecture of the Lucius Subsea Production System and the drivers behind it. Novel technologies are detailed including suction pile mounted Pipeline End Manifolds (PLEMs) and chemical injection backpressure regulator valves. Innovative installation techniques and highlights are described, including the use of laser metrology and a "strong back" system for rigid jumpers. Difficulties and lessons learned are also shared.
Best Practice Geotechnical Characterization and Pipe-soil Interaction Analysis for HPHT Pipeline Design
Authors: White D. J. , Westgate Z. J. , Ballard J-C. , de Brier C. , Bransby M. F. 
Published: April 2015

AbstractThis paper summarizes best practice cost-effective geotechnical design of high pressure high temperature (HPHT) pipelines, with an emphasis on HPHT lines in deep water, that are susceptible to lateral buckling and axial walking. It presents guidance on (i) tools for optimal geotechnical characterization of shallow seabed conditions along flowline routes and (ii) techniques to assess pipe-soil interaction parameters for input to pipeline structural modeling. Recent research into pipe-soil interaction measurement tools and analysis techniques has resulted in rapid advancements that are being quickly utilized in practice.Advanced pipe-soil interaction techniques, firmly rooted in soil mechanics theory and linked to the operational sequence of the pipeline through cycles of start-up and shut-down, are presented. They are used to demonstrate benefits that can be realized on typical projects to reduce pipeline walking predictions and the associated mitigation measures such as hold-back anchors. Recommendations cover the appropriate selection of characterization tools and analysis techniques based on project-specific requirements such as seabed geotechnical complexity, pipeline operating conditions, project timing, mitigation strategies for global stability and the desired approach to risk management and use of the observational method.The results, observations and conclusions presented in this paper represent the culmination of several years of research and development in pipe-soil interaction, as well as our experience on recent projects around the world where these techniques have been employed. The paper offers recommendations to guide both geotechnical studies and pipeline engineering work, and unlock benefits from maintaining close integration of these two disciplines through the design and operation of a pipeline.
Gulfstar - Porches and Pull Tubes - Comparing Two Riser Interface Options
Authors: Giles III George R. , Poll Philip , Converse Robin , Park Y. C. , Mao Charlie 
Published: April 2015

Abstract
Historically, Spar platforms have utilized both riser porches and riser pull tubes for interfacing steel catenary risers (SCRs) to the floating system. The riser porch requires a stress joint at the hang-off end of the SCR to withstand tension and bending loads at the fixed connection. The pull tube requires special hardware (e.g., a double-tapered stress joint) near the keel of the Spar where platform motions are first transferred to the riser system. Each of these options for the riser interface has advantages and disadvantages. The Gulfstar FPS utilized both pull tubes and a riser porch for riser interfaces.
This paper evaluates the experience designing and building the two different types of riser interfaces for the Gulfstar FPS and the experience offshore during installation of the risers. The paper quantifies the structural appurtenances required for each interface in addition to the equipment required for riser installation, which is significantly different for each interface type. The evaluation results in important lessons learned and recommendations for both types of riser interface strategies.
The paper also summarizes the keel interface utilized on the Gulfstar FPS. The Gulfstar FPS incorporates a different approach for the keel interface with the pull tube support compared to other recent Spar projects in the Gulf of Mexico. The results demonstrate the compatibility of the riser keel interface with the platform motions.
The information and results presented in this paper are applicable to engineers, designers and fabricators when evaluating riser interface options for floating systems, particularly Spar platforms.
Mooring of MRE Structures - Comparison of Codes, Including IEC
Authors: Stewart William P. , Achanta Vamsee 
Published: April 2015

Abstract
Objectives/Scope
This paper presents guidance on the design and selection of mooring systems, including anchors, specifically for Marine Renewable Energy (MRE) systems. It is based in part on the work of the ASCE COPRI MRE Committee over the last five years. The document gives guidance to MRE designers and analysts and gives confidence as to mooring systems reliability.
Methods, Procedures, Process
There are a few MRE systems, especially for Wave Energy Converters (WECs) that have evolved, which may be regarded as having a basically similar mooring system. However, selection of design criteria, including environmental conditions return period (and other parameters) as well as safety factors for WEC moorings has not yet evolved into a standard procedure. This paper contrasts the mooring system characteristics that are found for some typical WEC moorings when their design is selected to meet various mooring codes and standards. Codes considered include those published by: ISOAPIABSDNVLloydsIEC (International Electrotechnical Commission)US Navy
Results, Observations, Conclusions
Differences in the mooring codes are contrasted. Differences in the resulting mooring systems characteristics are contrasted resulting from using different codes. Differences in the systems are also contrasted with selection of different return periods and other environmental parameters. The results are also presented in the framework of the MRE Committee's approach to risk and reliability that has been developed by the oil and gas (O&G) industry over the last 40 years.
Novel/Additive Information
This paper presents an insight as to what is in the ASCE COPRI MRE guide for moorings
Lucius Offshore Installation of Flowlines, Risers and Topsides
Authors: Biggerstaff G. , Keith E. , Taylor B. , Taylor M. , Malarchick A. 
Published: April 2015

Abstract
This paper provides an overview of the design, fabrication and installation of Anadarko's Lucius Development flowlines, risers and topsides including all ancillary lifts required to fully complete the installation of the Lucius Spar.
The production flowlines, risers and associated structures were fabricated and installed by Heerema Marine Contractors US, Inc. utilizing the new build vessel DCV Aegir. At the time of contract execution the vessel was still under development and new vessel procedures as well as project installation procedures were required to perform the installation safely and within schedule. The export risers and flowlines were designed and fabricated by Technip USA, Inc. and installed using the Deep Blue reel installation vessel. The export risers were pulled in utilizing a custom built 1,000-ton capacity chain jack system designed, fabricated and installed by Versabar, Inc., The topsides installation was performed by Heerema Marine Contractors US Inc. utilizing the heavy lift vessel DCV Thialf for the 10,000-ton topsides lift and the heavy lift vessel DCV Balder for the ancillary lifts.
Some of the unique challenges addressed in this paper include some "firsts" which include the design and qualification of titanium stress joints on the export risers, the design and qualification of a diverless close in spool system as well as the design and qualification of a diverless pull head required to hang off the export risers. This paper also addresses the design and offshore installation of a 1,000-ton chain jack system which was designed late in the project life to install the export risers after the main topsides was installed. Additional firsts included the use of pile based riser base pipeline end manifolds which were designed to allow for a tight subsea architecture and sustain extensive bottom tension loads.
A Roadmap to Frontier Deepwater Drilling
Authors: Gutierrez Jose A. , Loftis Terry 
Published: April 2015

Abstract
Offshore deepwater drilling is a complex activity requiring the use of a variety of technologies to enable safe and reliable operations. Year after year, the industry has progressively been able to drill deeper; reaching depths in excess of 10,000 feet, using state-of-the art rigs designed to theoretically reach up to 12,000 feet. However reaching even deeper (15,000 feet+) water depths using existing hoisting and subsea equipment architectures and relying technologies is not feasible. For example BOP hydraulic accumulators within a reasonable weight and size are not viable to support emergency functions beyond 12,500 feet using the existing open loop hydraulic architecture. The prevailing 'go bigger to go deeper' bravado conflicts with the physical limitations of today's mechanical systems and supporting structures. Heavier hook-loads drive higher power consumption, larger power plants, higher fuel consumption and storage, larger derrick structures and subsequently, less variable deck-load. Furthermore, conventional drilling riser length, volume and weight increase, thus compounding the hook-load dilemma and the cycle continues. New designs, materials and concepts are required to reach the depths of this new frontier! This paper presents a roadmap for the introduction of a set of technologies and system architecture(s) to address these challenges.
Geophysical Methods for the Mapping of Submarine Massive Sulphide Deposits
Authors: Kowalczyk Peter , Bloomer Stephen , Kowalczyk Matthew 
Published: April 2015

Abstract
In 1977, the first black smoker was discovered on the East Pacific Rise. Since this discovery, many more hydrothermal vent occurrences have been discovered in the deep ocean. These vents are associated with compact high grade copper, gold, and zinc deposits that are being actively explored for by national and private organizations.
Exploration for these deposits usually begins with ship borne sonar mapping and towed water chemistry samplers. From bathymetric maps, potential targets for more detailed mapping with underwater vehicles are defined. Remotely operated vehicle (ROV) and autonomous underwater vehicle (AUV) mounted turbidity, pH, and oxidation reduction potential (ORP) sensors, magnetometers, electromagnetic (EM) systems, high-resolution multibeam echosounder (MBES) bathymetry, sidescan sonar and subbottom profiler surveys are used to delineate the extent and nature of the submarine massive sulfide (SMS) deposits.
EM surveying can be used to determine the resistivity of near-surface and subsurface structure. SMS deposits fall into two categories; zinc rich non-conductive and conductive copper-gold deposits. One system is an ROV-mounted EM system that operates near the seafloor (Kowlaczyk, 2008). It comprises a transmitter coil wrapped around the ROV and an electric field sensor mounted close to the ROV. This system has successfully mapped high-conductivity zones corresponding to high grades of copper and gold. This system has detected blind mineralization at a depth of several meters, but does not penetrate beyond five or ten meters into the ocean floor. It does outline the limits of the system accurately, and has been used to direct resource-definition drilling of SMS deposits.
Modelling shows that buried SMS deposits can be mapped using a controlled source electromagnetic (CSEM) system. A CSEM system consists of an electrical transmitter and one or more electric field receivers that are either on the seafloor or towed behind the transmitter. SMS deposits are conductive and will channel electrical current. Since the conductivity of the ocean is constant, electrical fields are a proxy for current density. Modelling shows that SMS targets produce a readily detectable electrical field anomaly. Using 3D inversion of the CSEM electrical field data, subsurface SMS deposits can be mapped.
SMS deposits can also be mapped using seismic methods. The depth of water and the deposit geometry make it difficult to deploy standard systems. A new system using a vertical cable array and a surface source has successfully mapped SMS deposits in 3D.
This paper will review the use of EM and seismic methods successfully used to map SMS deposits.
Ministry in the presence of God (<i>coram Deo</i>) according to Exodus
Authors: Breed Gert 
Published: April 2015

This article describes ministry in the presence of God (coram Deo) as revealed in the Book of Exodus. At the outset, the structure of the Book of Exodus is analysed and the relevant results are given. Then a study is made of what it means, according to Exodus, to be in the presence of God. An effort is also made to describe the service of the people of God in light of the study of coram Deo. The results of the investigation are continuously applied to the practical work of the congregation. The article concludes that the ministry can be largely enriched when the congregation are purposefully guided to come together, serve and live consciously in the presence of God.Bediening in die teenwoordigheid van God (coram Deo) volgens Eksodus. Hierdie artikel beskryf die lewe voor die aangesig van God (coram Deo) soos dit in die Eksodusboek geopenbaar is. Aanvanklik word die struktuur van die Eksodusboek ontleed en die tersaaklike resultate weergegee. Daarna word ’n studie gemaak van wat dit volgens Eksodus beteken om voor die aangesig van God te wees. Daar word ook gepoog om die dienswerk van God se volk te beskryf in die lig van die studie oor coram Deo. Die resultate van die ondersoek word deurlopend toegepas op die praktiese dienswerk van die gemeente. Die artikel kom tot die gevolgtrekking dat die bediening grootliks verryk kan word wanneer die gemeente doelbewus begelei en toegerus word om bewustelik voor die aangesig van God saam te kom, te dien en te leef.
Real Hypersurfaces in Complex Two-Plane Grassmannians with GTW Harmonic Curvature
Authors: de Dios Pérez Juan , Jin Suh Young , Woo Changhwa 
Published: April 2015

AbstractWe prove the non-existence of Hopf real hypersurfaces in complex two-plane Grassmannians with harmonic curvature with respect to the generalized Tanaka–Webster connection if they satisfy some further conditions.
A High-Order Central ENO Finite-Volume Scheme for Three-Dimensional Low-Speed Viscous Flows on Unstructured Mesh
Authors: Charest Marc R. J. , Groth Clinton P. T. , Gauthier Pierre Q. 
Published: April 2015

AbstractHigh-order discretization techniques offer the potential to significantly reduce the computational costs necessary to obtain accurate predictions when compared to lower-order methods. However, efficient and universally-applicable high-order discretizations remain somewhat illusive, especially for more arbitrary unstructured meshes and for incompressible/low-speed flows. A novel, high-order, central essentially non-oscillatory (CENO), cell-centered, finite-volume scheme is proposed for the solution of the conservation equations of viscous, incompressible flows on three-dimensional unstructured meshes. Similar to finite element methods, coordinate transformations are used to maintain the scheme’s order of accuracy even when dealing with arbitrarily-shaped cells having non-planar faces. The proposed scheme is applied to the pseudo-compressibility formulation of the steady and unsteady Navier-Stokes equations and the resulting discretized equations are solved with a parallel implicit Newton-Krylov algorithm. For unsteady flows, a dual-time stepping approach is adopted and the resulting temporal derivatives are discretized using the family of high-order backward difference formulas (BDF). The proposed finite-volume scheme for fully unstructured mesh is demonstrated to provide both fast and accurate solutions for steady and unsteady viscous flows.