bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Simulated and Full Scale Disconnection of Turret Buoy
Authors: Bech Arild , Daniel Jeremiah , Hovde Geir Olav , Vinje Tor 
Published: May 2013

Abstract
This paper addresses mooring design methods, reveals records of site tests, and also compares the conventional theoretical numerical modeling approach with a real full-scale disconnection of this challenging scenario. The FPSO BW Pioneer set a new world record for deepest mooring system on a production unit at 2,500m (8,200ft) of water depth in the US Gulf of Mexico. The unit also pioneered this type of facility (FPSO) in the US Gulf of Mexico.
This area of the globe is prone to hurricanes. The decision was made to proceed with a concept that would allow the vessel to detach from its mooring and risers system and sail away to sheltered waters when necessary. The mooring as well as all risers and umbilicals sink to a depth that is safely below the waves in case of a major storm.
This system installed is the first production module for two deepwater fields, Cascade and Chinook, both operated by Petrobras America Inc. with the FPSO BW Pioneer.
Various connect - disconnect scenarios were identified during the design phase. Since the system is detachable, the disconnection and reconnection dynamics were analyzed in detail. Due to the complexity of the interaction between the STP™ turret buoy and the mating cone, a model was introduced to better evaluate the local effect of dragging and hydraulic suction combined with the vessel motion. This effect is paramount to the integrity of the riser and umbilical structure, as well as to prevent collision between the vessel and the buoy. The model is described and simulations emphasize vertical velocities and accelerations, as compared to traditional methods of computation.
At the time, it was unknown whether any previous projects had ever compared the theoretical numerical model with a real full-scale disconnection. The decision was made to proceed with an instrumented site free-drop test, using customized equipment similar to what Petrobsas uses to monitor the trajectory of the Petrobras' torpedo piles during installation. This paper presents to the Industry these site test results and draws conclusions about how accurate or robust design premises are when performed by state of the art design tools used on this project.

Introduction
The Cascade and Chinook fields are located in the Walker Ridge area of the Gulf of Meixco and are being produced from the FPSO BW Pioneer that is located in WR/Block 249. The Cascade field was discovered in 2002 and Chinook field was discovered in 2003.
The mooring with turret buoy was installed in late 2009 and the FPSO BW Pioneer was first connected to the mooring late 2010. Installation of the mooring and connection of the FPSO set a new world record for deepest mooring system on a production unit at 2,500m (8,200ft) of water depth.
General Design of Super Platform's Installation in South China Sea
Authors: Bai Xue-ping , Jia Xu , Yi Cong , Li Da , Hou Jin-lin , Fan Mo 
Published: May 2013

Abstract
This paper mainly introduced the scheme design of Liwan 3–1 CEP platform's jacket and topsides in South China Sea. The load-out weight of the CEP platform's jacket and topsides both exceed 30,000 tons, it is the largest platform in Asia. The jacket of Liwan3-1 CEP platform is installed by launch and the topsides is installed by float-over method. They are very hard to install in South China Sea because of challenges in large weight and the harsh environment condition. To choose appropriate installation barge and installation weather window are the key problems. The paper introduced the selection of installation barge, modified HYSY229 is ascertained to execute the jacket launch and topsides float-over installation of this platform. The paper introduced the selection method of float-over installation weather window in South China Sea, and the key design technology of jacket launch and topsides float-over installation. After a lot of design work and demonstration, a method of stability assessment during jacket launch is mentioned in this paper, a creative sway fender design, mooring system design and LMU arrangement of topsides float-over installation in barge are introduced in this paper. The general design ideas and design method are ascertained successfully, it ensures the progress of offshore installation engineering in Asia.

Introduction
With the development of the South China Sea deepwater oil and gas fields, the platforms also gradually develop to a large or very large scale. It is necessary to minimize the number of platforms under the premise of ensuring security, in order to save the project investment. Thus, some super platforms come into being. Super platform's size and weight leads to fairly high requirement of construction machinery and extremely limited options for installation barge. Therefore, the scheme design of super platform's jacket and topsides installation becomes a challenge.
Development and Qualification of End Fittings for Composite Riser Pipe
Authors: Roberts Damon , Hatton Stephen Anthony 
Published: May 2013

Abstract
Whilst much interest is often focussed on the composite pipe body it is often forgotten that a reliable end fitting is a prerequisite of a successful composite pipe application and further that the design challenge of the end fitting is more challenging than the pipe itself.
The purpose of this paper is to present the end fitting arrangement for a composite pipe manufactured from carbon fibre and PEEK polymer. The paper describes the design approach and testing/qualification program employed for the end fitting to demonstrate reliable application in a critical and structurally demanding application such as for a deep water dynamic riser.
The paper summarises historical design approaches and design alternatives and explains the reason for selecting the proposed arrangement. It presents the design process used to develop the design and to predict its structural response. It discusses manufacturing issues and describes the test program conducted to prove the end fitting performance.
Industry focus is often on the pipe rather than the end fitting. However the latter often presents a more difficult design challenge. Without a reliable design solution and methodology composite pipe application cannot be considered. The development work presented in the current paper therefore presents an important step towards application of composite technology on demanding riser applications.
An end fitting with reliable structural and sealing performance is a prerequisite for the successful application of composite pipe. Historically, this has proven to be a difficult challenge and end fitting performance limitations have been cited for the slow introduction of composite pipe technology. The current paper presents a new design approach to the problem, made possible by a unique manufacturing process and a better understanding of the composite metallic interface, which together allows the end fitting problems to be resolved. The paper describes fundamentals of the design approach, the development work conducted, manufacturing and qualification testing. The paper discusses the function specification, key design features, FEA approach and results, codes and standards, testing results under combined load conditions and fatigue testing results.

Introduction
Design, fabrication and installation of riser systems for floating production is a complex challenge. Constraints such as maximum payload capacity and design issues such as internal and external corrosion, fatigue capacity, thermal insulation, weldability and susceptibility to sour service conditions conspire to make riser design one of the most demanding challenges in the offshore industry today. The magnitude of this challenge has grown, perhaps non linearly, as water depths have continued to increase over the last 20 years. Also operating pressures and temperatures have increased, particularly in the last 10 years, with the focus on presalt and subsalt reservoirs.
Effects of Stress History on Failure Behavior of Shallow, Marine Muds From the Northern Gulf of Mexico
Authors: Zhao Xin , Dugan Brandon 
Published: May 2013

Abstract
We explore the relation of stress history and failure mechanics of sediments from the Ursa Basin, Gulf of Mexico using direct simple shear experiments. We consolidated specimens to different preconsolidation stresses via load-increment consolidation; then sheared each specimen under undrained conditions to determine shear strength, shear-induced pore pressure, and their responses to stress history.
The stress history influences sediments properties before failure, and may impact failure dynamics. By shearing sediments with different initial porosity or different initial stress, we study how pre-failure conditions influence failure behavior (e.g., contractional or dilational). This can help us define if failing sediments are prone to contract and accelerate, to creep, or to dilate and stop failing.
Preliminary results on mud samples from the Ursa Basin indicate that as burial depth increases from 430 to 1340 cm below sea floor (bsf) the cohesion decreases from 18 to 6.5 kPa and internal friction angle increases from 10° to 21°. The preconsolidation stress for these specimens ranges from 16 to 42 kPa and experimentally derived peak shear strengths are 30–63 kPa. To investigate stress history, we studied three specimens from 1315–1340 cm bsf that were consolidated to different maximum effective vertical stresses or 52, 104, and 208 kPa. The specimens show an increase in shear-induced pore pressures from 38 to 73 to 180 kPa. The normalized undrained shear strengths are 0.29, 0.27, and 0.23 at maximum shear. This indicates that the normalized undrained shear strength decreases with vertical consolidation stress, whereas the maximum shear-induced pore pressure increases with vertical consolidation stress. Together these parameters may influence the depth at which failure occurs and the post-failure dynamics of these mud-rich sediments, but additional work is needed.
All these data are part of the geotechnical characterization of shallow, marine sediments from the northern Gulf of Mexico. These types of data will be used to test and calibrate sediment failure models which are vital for subseafloor geohazard analyses and offshore infrastructure development. Our study may lead to new assessment techniques of submarine landslide risks and provide new approaches to mitigate risk.
Case Study: Surface-controlled Formation Isolation Valves and Their Application as a Barrier for Temporary Well Suspension
Authors: Thai Dan , Guven Oguzhan , Mendonca Joao 
Published: May 2013

Abstract
The industry trend of E&P operationsfrom deep water subsea wells is increasing the demand for deepwater drilling rigs. To increase rig availability, operators are resorting to a new strategy of transferring the subsea tree installation responsibility from the offshore drilling rig to a subsea equipment support vessel. The installation from a rig can take 1 to 3 weeks; transferring this responsibility to the support vessel enables the rig to move to the next well sooner and offers significant rig time savings.
This paper introduces a fit-for-purpose surface-controlled formation isolation valve (SFIV) designed for the temporary well suspension that is required as a part of this strategy. The valve was developed, tested, and manufactured in accordance with the ISO-28781 standard. A case study demonstrates the operational time savings achieved by suspending a subsea well with the and landing the tree on heave-compensated wire, call the tree-by-wire technique. Temporary well suspension can be achieved by using plugs or mechanical barrier valves. If plugs are used, the rig must return to remove them after the vertical tree installation, which would partially negate the benefits of the new strategy. Therefore, to fully realize the potential of this new strategy, the SFIV was designed to provide a mechanical barrier that could be remotely opened from the support vessel through application of pressure in the hydraulic control lines without loss of actuation capacity. It's a true fail-as-is valve that eliminates the risk of loss of well control in case of a system failure, which has critical importance in well suspension applications.
Starting in November 2010, several subsea wells around the world were successfully suspended with the SFIV valves. Besides using the SFIV as a suspension valve, operators can use it to perform production build-up tests, downhole lubricator valve for deployment of long production loggin or pereforating guns. This is possible since the valve could be opened multiple times with high differential pressure across the ball valve without any adverse affects on its sealing capacity.
Innovative Geosteering Technology Utilized in Drilling Smart Multilateral Wells, Kuwait
Authors: Estarabadi Javad , Gezeeri Taher M. N. , Padhy Girija Shankar , Silambuchlvan Jeevan , Ferroni Gionata , Al-Anezi Khalaf K. , Ismael Abdulaziz , Latif Ahmad Abdul 
Published: May 2013

Abstract
The Burgan Reservoir having vertically stacked channel sands, fault network connected to the aquifer and hydrocarbon viscosity of about 40cp has the potential for premature water breakthrough leaving behind zones of by-passed oil. Placing and completion of horizontal wells in such reservoirs is a challenge necessitating collaborative approach from petroleum geoscience, reservoir engineering and petroleum engineering. The current work scope describes placing of the horizontal wells in this kind of heterogeneous reservoir through an integrated approach involving all segments of petroleum geoscience. The workflow incorporates utilization of real-time geochemical analysis (XRF) on rock cuttings, LWD data and real-time petrophysical evaluation to geosteer the smart multi-lateral wells in zones of highest flow potential and less structural complexity. The pre job planning had two components such as:building a geosteering model based on offset well logs, geological and geophysical information andpreparation of geochemical model based on XRF analysis of core chips from offset wells.
The later model was calibrated through logs and utilized further to predict key rock attributes such as:detailed lithological variations generally beyond the resolution of LWD logs,detailed mineralogy to determine the diagenetic overprint anddepositional environment of different Burgan sand facies.
The real-time geosteering operation was guided not only by the LWD tools but also through the continuous interpretation and integration of XRF and petrophysical analysis. Azimuthal Litho-density Images were interpreted in real-time not only to understand the formation dip but most importantly to identify cluster of fractures/faults, which was further complemented with XRF and seismic data analysis. Nature of the fractures/faults (open or healed, contribution to porosity and communication with water zone) were inferred from the several cross plots and Dipole-sonic data in real time and further validated with XRF obtained elemental markers. Several other cross plots along with quick volumetric analysis provided information on rock quality/type and fluid saturations.
The integrated approach not only has resulted in successful geosteering and placing the wells with maximum reservoir contact but also was very instrumental for (i) isolation of potential trouble zones, (ii) segmentation of horizontal sections and (iii) optimization of nozzle sizes of the ICDs and hence planning of smart completion designs.
Impacts of Technology on Communicating Weather Windows for Offshore Construction, Drilling and Intervention Operations
Authors: Hasling Jill 
Published: May 2013

Abstract
With the rapid development of computing and mapping software, meteorologists are able to create graphical marine weather forecasts to provide drilling operations a better picture of the weather windows for their operations. By being able to combine satellite, radar, operation locations, wind and wave forecasts onto one map, the operator has a quick overview of the weather's impacts on his/her operations. Global models are now available every 6 hours giving various forecasts of winds and waves out to 15 days. This information can be used to have a preliminary view of what weather one could encounter for support vessels or for weather sensitive operations. Examples of weather in the North Sea, Gulf of Alaska, and Gulf of Mexico will be given to show how technology has changed and how the meteorologists communicate the weather to the oil and gas industry.
Execution of New Drillship Project - Perspectives From Owner, Class, Builder and Designer
Authors: Wang Xiaozhi , Lee Suck-Hwan , Webb David L. , Ren Harry H. , Lee Y. C. , Hendriks Sjoerd M. 
Published: May 2013

Abstract
Drillships have proven to be an attractive type of mobile offshore drilling unit due to their excellent mobility and large variable load capacity. The technical challenges of the new generation of ultra deepwater drillships include greater efficiency and increased capability of both facility and hull structural design. Modern ultra deepwater drillship designs, i.e., sixth generation and beyond, are capable of operating in water depths of up to 12,000 feet and drilling depths of up to 40,000 ft. These drillships feature new developments in design and operation that require cooperation and collaboration by the designer, builder, owner and classification society. Compared with earlier generation designs, these new ultra deepwater drillships present unique challenges in their design, construction and classification.
The paper presents how these challenges were addressed in a recent drillship new construction project from the perspective of the owner, classification society, builder and designer. This includes the design itself, construction techniques applied, owner's requirements and classification design verification. Several special aspects of this drillship, including Metacentric Height-controlled drilling and variable draft operation, are also addressed.
Buoyant Tower: Drilling and Production
Authors: Mueller Wayne , Blanco Hugo 
Published: May 2013

Abstract
The CX-15 platform was installed off the coast of Peru in block Z1 in September 2012. The buoyant tower is designed for tender assist drilling and production. This is achieved through two opposing cantilevered 12-slot drilling and production templates and guide assemblies. By the time of presentation, the initial drilling phase will be underway and data from the whole process will be available for review, discussion and evaluation. The platform is the world's first application of a proprietary design that is a fusion and combination of existing and proven technology from deep water cell spar floating platforms, compliant tower structures and shallow piled foundations. The paper presents an overview based on project information for the drilling operations from the CX-15 buoyant tower and the use of a modified onshore rig with barge tender assist. The drilling philosophy is designed to efficiently enable rapid drilling and completion of wells and reduce time to first oil. The well design includes the innovative use of the 20 in. conductor as a cost effective bend-restrictor at the mud-line. The design and provision of a fully integrated topside facility is " state-of-the-art " offshore Peru. Lessons learned from drilling and production operations are shared.

Introduction
The CX-15 platform is located approximately seven miles off the northwest coast of Peru in a water depth of approximately 175 ft (see Fig. 1). The platform consists of a three-level, four-legged deck supported by a buoyant tower hull. The platform is a drilling and production unit and would generally be compared to a fixed jacket platform with an API skidded platform rig. To reduce the size and payload of the platform, most drilling support equipment is located on a tender barge moored adjacent to the platform.
The hull structure is a buoyant tower and consists of four cellular columns and an integrated suction-can foundation centered below the four tubular cells. Because the columns are arranged close together without a moon pool, two wells bays are located outside of the tower's footprint. The drilling rig is supported by cantilevered wing decks (see Fig. 2).
In addition to the wells, the platform is equipped with production equipment to produce, separate, and treat oil, gas, and water from the CX-15 field. Stabilized and dehydrated sales oil is transferred by pipeline to an existing FSO moored in the area. Wet associated gas is compressed and transferred by pipeline to the existing CX-11 platform. The produced water is treated on the platform and can be re-injected locally or transferred by pipeline to the existing CX-11 platform. Provisions for lift gas and gas injection are also included.
The drilling rig mast, drive, and skidding system are newly constructed but based on an existing telescoping land rig. The land rig mast design was upgraded for use on the buoyant tower and the skidding system and support base were designed and constructed specifically for this project.
Thin-Wall Approximation: Implications for the Expansion and Global Buckling of Thick-Walled, High-Pressure Flowlines
Authors: Kurusamy Doraraju 
Published: May 2013

Abstract
R.E. Hobbs in 1984 addressed in detail the buckling of heated pipelines using thin-wall theory. His work was instrumental in starting much interest and active research in the global buckling of pipelines. Since then, publications on pipeline expansion and global buckling base their analyses on thin-wall theory. Joint Industry Projects like SAFEBUCK and HOTPIPE and the industry's recommended practice and guidance have also mostly addressed global buckling of pipelines based on thin-wall formulation. Presently engineers use thin-wall FEA methodologies to routinely design flowlines/pipelines for axial expansion and global buckling. Thin wall theory is accurate for ratios of D/t &gt;20. High pressure thick-walled flowlines can reach values of D/t&lt;6 and the continued use of thin-wall theory can lead to flaws in their design.
Although a few authors have addressed the topic of pressure-induced axial strains of thick-walled pipelines, the lack of need for heavy walled pipes has not motivated the industry to use thick-wall formulation. Although industry is aware that the use of thin-wall theory for thick-wall pipelines can lead to design flaws for the pressure-induced pipeline expansions and buckling mitigation, there has not been a comprehensive comparison between thin-wall and thick-wall theory based on experiment, analysis and numerical modeling in this regard.
The purpose of this work is to quantify the errors due to the inappropriate use of thin-wall theory for thick-walled pipeline expansion and global buckling. Experimental and FEA results are in excellent agreement with analytical results. Parameters relevant to axial expansion and global buckling of thick-walled flowlines under high pressure loads using thick-wall theory are compared against those obtained using thin-wall theory. It was found that thin-wall theory can substantially underestimate the pressure-induced axial expansion of thick-walled flowlines, in some cases errors in excess of 80%. With errors of such magnitude caused by the improper use of thin-wall theory, the design for flowline/pipeline expansion and global buckling (lateral and upheaval) mitigation can be inadequate and thus lead to non-conservative design especially in scenarios where pressure-induced axial strains dominate (e.g. hydrotest case) or when they are not negligible compared to axial strains caused by temperature.