bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new Offshore Mooring Anchor for Hard Grounds
Authors: Ozmutlu S. 
Published: April 2017

This paper presents the development and the testing of a new anchor for hard seabed conditions. The anchor development involved computer modelling, laboratory scale model testing, and eventually the full scale anchor testing offshore. The goal of the development was to expand the suitability and applicability range of drag embedment anchors in hard soils and soft rocks.
The anchor development process is explained and the theoretical models for hard ground anchoring are introduced. The laboratory testing conditions and the results of laboratory tests are presented. Following the model scale qualification phase in different soil types and strengths in the laboratory, the full scale testing of the new anchor is carried out at selected offshore locations. The offshore testing conditions, the instrumentation and measurement techniques, and the results of offshore testing are evaluated and presented. In order to benchmark the performance of the new anchor, both laboratory tests and field scale tests are run against a reference anchor which is tested under the same conditions.
The model scale and field scale testing results show that the new anchor is able to penetrate into harder grounds and generate substantial holding capacity. The penetration ability and the stable holding capacity of the new anchor is around 22% to 47% higher than the existing anchors of comparable category. The offshore scale test results have proven that the new anchor has increased the offshore mooring capability in hard soils and soft rocks.
It is expected that the results of this work will allow a better understanding of anchor behavior in hard soil and soft rocks. The results and the technology developed will be beneficial to the oil/gas and energy sectors in general and the offshore mooring industry in particular. The new technology is expected to provide a practical and cost effective anchoring solution in challenging frontier areas (e.g. Arctic, Northwest Shelf Australia, Persian Gulf, and many shallow water areas of the world), and in emerging industries like Floating Renewables and dredging/offshore construction.
Supplying Additional Power Subsea through Intervention ROV Systems
Authors: Restivo A. , Glenn C. , Williams L. 
Published: April 2017

Abstract
Current remotely operated vehicles (ROVs) require dedicated umbilicals to provide communications, enable control, and to power three-phase motors on the subsea vehicle. The standard architecture does not permit ROV umbilical power to be used for separate devices, so additional equipment – such as dredges, pumps, or subsea hydraulic power units – requires its own dedicated power, control lines, and topside equipment.
This paper explores the ways and means of expanding existing ROV technology to enable driving additional subsea equipment using ROV umbilical power. The discussion focuses on the development of a smart subsea medium-voltage switch and a mate-able hybrid medium voltage/fiber optic connector for subsea intervention systems.
The paper has four main sections. First, the paper presents the technical requirements for a subsea switch and hybrid connector operating at water depths exceeding 3000 m. Second, the benefits of expanded power distribution from an ROV, including reduced equipment requirements, enhanced safety, and increased operational flexibility are discussed. Third, the challenges associated with designing and testing the subsea switch and hybrid connector technologies are reviewed. And fourth, the paper outlines the roadmap of expected progress toward achieving the goal of providing power to additional devices through intervention ROV umbilicals.
Model Test Campaign Overview for the Turritella FPSO for the Stones Field
Authors: Carrico Todd , Leverette Steve 
Published: April 2017

Abstract
Shell Offshore Inc. ("Shell") Stones Project is a record breaking Floating Production Storage and Offloading (FPSO) unit. This novel disconnectable FPSO solution incorporates numerous technologies which help to redefine the state of the art and extend the capability envelope for deepwater applications. Critical to the success of this project was the systematic development of these enabling technologies during the time frame of the project. A key component of this development process was the use of model testing. Over the course of the project, a comprehensive set of campaigns were performed. During the Front End Engineering Design (FEED) effort, model scale testing was utilized to provide insight into relevant hydrodynamic phenomenon. Later during project execution, the testing focus shifted to confirming the effect of particular design changes. This paper gives an overview of each campaign. It presents a timeline of testing and shows how their timely results were integrated into the design process.
Eight different campaigns will be discussed in the paper. They fall into three categories; Buoy Turret Mooring (BTM), FPSO, and Turret. The early campaigns focused on the disconnectable buoy and mooring systems. Given the novel aspect of the design, which is the world's largest BTM buoy, verifying and validating its hydrodynamic performance took precedence. This was performed for both connected and disconnected scenarios. The FPSO campaigns were dedicated to more traditional vessel issues. Here performance aspects of the heavily modified vessel were quantified through resistance tests, captive model maneuvering tests, wind tunnel tests, and in place greenwater tests. Lastly, the Turret Campaigns focused on measuring wave dynamics inside the moonpool while underway and assessing the performance of potential mitigating design features.
Development of a Flexible Pipe for Deep Sea Mining
Authors: Rongau J. , Viale S. 
Published: April 2017

Abstract
During subsea mining operations, minerals are extracted from the seabed, typically at about 2000m depth, and pumped with water through a riser pipe to a surface processing vessel. TechnipFMC, through its subsidiary Technip France, is the lead of a consortium comprising COMEX and DCNS which has been awarded a contract by BPIFrance to develop a pilot subsea mining system. The scope includes the development of a flexible riser. This flexible riser comprises an inner wear protection layer to resist the wear from the slurry, covered by a structure to withstand mechanical loads applied to the flexible during its lifetime.
In order to select the most appropriate anti-abrasion material, a large scale bench test has been built to reproduce realistic flow in a piping system and compare wear on different materials; rubber, polyethylene and stainless steels. Complete analysis of the wear patterns has been conducted with the expertise of a laboratory. A statistical comparison between materials is presented. The response to wear, depending on material, geometry and position, is better known. One of the materials shows much better wear resistance than the others and is selected for further development.
The next step is the development and qualification of the manufacturing process for the wear protection layer. This process has to be as much as possible compatible with current flexible pipe manufacturing plant. Parameters such as thickness, diameter or length of the layer should be adaptable according to needs. The compatibility with the pipe mechanical structure has to be tested as well. To meet these requirements, existing manufacturing processes are limited. At the time of writing this paper, different manufacturing methods to incorporate this wear protection layer within a continuous industrial flexible production are currently under investigation. Several prototypes will be realized for each manufacturing step. Prototyping is under test and will be presented in a forthcoming presentation.
Standardizing Business Processes within Oil and Gas Markets to Reduce Costs
Authors: Campbell E. 
Published: April 2017

Abstract
The objectives of this proposed paper are to: Demonstrate the potential cost reduction benefits derived from implementing a standard process for customers to purchase itemsCompare the oil and gas market to industries where common business standardization philosophies are being usedHighlight areas of potential cost savingsA review of previously published studies and common project management methods will be used.
Identifying crossover of processes from industries with a history in standardizing will assist in drawing conclusions about potential applications in the oil and gas industry. Common business philosophies including Kiezen and Stage Gate, will be reviewed and highlight common themes between oil and gas and other markets and identify cost saving potential. Applicable common management methods will be described will be supported by examples of successful implementation of the processes. The identified cross-over opportunities will be compared in cost models to demonstrate effectiveness The mature nature of the oil and gas industry presents an opportunity for standardization because we now have historic project data and can identify opportunities for adopting common practices. Papers investigating process standardization within the oil and gas industries are typically rare compared to health markets, for example.
The implementation and awareness of these business philosophies has recently increased. Due to a dramatic decline in the oil price, businesses have been forced to review their business practices and identify opportunities for cost savings. These ideologies, if implemented, have the potential to transform the competitive business market and improve efficiency within the industry, effectively reducing overall costs for companies. This is crucial to keep the oil and gas market buoyant and evolving. The comparison of common standardization business practices in the oil and gas market is often met with skepticism. More research and discussion on the subject, however, could greatly benefit the industry.
Production Chemistry: Exposing Hidden Treasures or Generating Complications?
Authors: Zhang Ping , Harris Lorraine , Demiroglu Muge , Gokool Andre 
Published: April 2017

According to a recent study, more than 50 percent of the world's energy currently comes from oil and natural gas. So how does Production Chemistry discipline play a role in this? Can we use the discipline to enhance or accelerate production? And what happens if we get it wrong? Will it have a detrimental impact on production?
The Production Chemistry threats to business are getting more challenging and frequent, reflecting the changing complexity of our Project and Operations portfolio (deeper water and complex interventions, longer subsea tie backs leading to colder fluids and more wax / hydrate challenges; or smaller tieback to hosts operated by others yielding compatibility challenges).
Production chemistry threats in Project and Operations represent a significant challenge to safe and competitive operations. The impact of getting it wrong can be severe, leading to deferrals and increased operational costs. The root causes of many of these deferrals can be attributed to late or unstructured production chemistry involvement during the Project stage and limited support during Operations stage.
The objective of this paper is to highlight the importance of understanding the financial impact of production chemistry decisions to safety, production assurance, operational expenditure (OPEX) and capital expenditure (CAPEX) for Project and Operations. Moreover, this paper will highlight the criticality of engaging production chemistry at the appropriate project phase to get the desired outcome. This paper provides a number of case studies. In a number of cases, production chemistry engineers correctly evaluated the project threats during engineering design, leading to a correct selection of preventative barriers which proved to be financially favorable, and reduced HSSE risks throughout life of the asset. In addition, one case study describes the operational experiences where the impact of production chemistry was incorrectly assessed and a production loss was incurred during Operations stage.
Based on these case studies, production chemistry engineers should be cognizant of the impact of their decisions on the projects including threat assessment and barrier selection throughout the project lifetime. In addition, the production chemistry engineers should be able to effectively communicate their technical decisions and associated reasoning and values provided with the project stakeholders.
Investigations into Observed High Frequency Mooring Line Dynamic Behaviours
Authors: Jayasinghe K. , Carra C. , Potts A. E. , Kilner A. A. 
Published: April 2017

Abstract
As part of improvements to the integrity management practices for two in-service FPSO mooring systems, detailed reviews of existing video inspection data were undertaken. These reviews identified separate high frequency mooring system dynamic responses in frequency ranges higher than typical wave frequency responses. In relatively benign conditions associated with ROV-based inspection activities, torsional vibrations in deep water wire rope sections were observed. In a moderate water depth system, vortex induced vibration (VIV) excitation of a wire rope segment, leading to high frequency oscillations of chain links within the chain hawse tubes on a turret moored system, were also observed. These oscillation frequencies were typically an order of magnitude higher than those arising from wave frequency motions. The implication of these observed high frequency motions was that there were potential fatigue and wear degradation mechanisms that had not been accounted for in the mooring system design. A review of the observed high frequency response mechanisms - torsional vibrations and VIV excitation of mooring line segments - was performed followed by an assessment of the implications on mooring system design and ongoing integrity. The theoretical foundations for the two mechanisms were identified, and the frequency and amplitude of the resultant motions and component stress ranges evaluated. The degradation effects of the two mechanisms were then assessed in terms of both the core mechanisms and the child degradation processes they may initiate (e.g. wire rope segment VIV leading to increased chain wear). A review of different mooring system configurations and water depths was performed to identify the propensity for these mechanisms to occur and their potential for adverse impacts on mooring line integrity were evaluated. For each mechanism, the key influence parameters on the observed high frequency response were identified. The potential impacts on overall mooring system integrity were evaluated, along with the implications for the inspection strategies to verify the ongoing condition of the mooring components. These mechanisms show that mooring system designers must be aware of the dynamic responses that can be excited with typical mooring systems. Without paying due attention to these potential effects at the design stage and during operation, the degradation mechanisms that may be initiated by these effects may be detrimental to the overall long-term integrity of the mooring system.
Investigations Into Break Strength of Offshore Mooring Chains
Authors: Potts A. E. , Farrow G. , Kilner A. A. 
Published: April 2017

Abstract
The first phase of the Chain FEARS (Finite Element Analysis of Residual Strength) Joint Industry Project (JIP) aimed to develop guidance for the determination of a rational discard criteria for mooring chains subject to severe pitting corrosion which, based on current code requirements, would otherwise require immediate removal and replacement.
Critical to the ability to evaluate the residual strength of a degraded chain, is to have an accurate estimate of the chain in its as-new condition, providing a benchmark for any loss in strength associated with severe corrosion or wear. A Finite Element Analyses (FEA) residual capacity assessment method was developed and correlated against available break strength test data of degraded links as part of the JIP. FEA were conducted of as-new chain links in accordance with this validated methods, which when compared with current Class Rules specified Minimum Break Load (MBL) demonstrated a significant disparity between Predicted Break Load (PBL) and the codified MBL, particularly for larger chain sizes. It was identified, consequent on this inconsistency in MBL with respect to chain size that inconsistency in proof loading would also result for chains of larger size.
Consequently further investigations were carried out with the objective of:Determining an alternative formulation for the break strength of studlink and studless chain, thereby allowing comparison with the current Class Rules break strength formulation.Assessing the extent and effect of inconsistencies in the Conventional Proof Load FormulationEstablishing the origin and the technical basis for the Conventional MBL formulae.Assessing the validity of the Code MBL with respect to Actual Break Load (ABL) of common studlink mooring chain and the implications of using an alternative Amended Formulation for as-new chain strength.
The basis for the determination of the current Class Rules on chain strength is established and in doing so serves to explain the a significant disparity between PBL and the codified MBL that is evident particularly for larger chain sizes. An alternative formulation for the break strength of as-new studlink and studless chain is presented. It is recommended that further investigation be conducted to establish an alternative proof load formulation optimized for fatigue endurance.
A New Quantitative Predicting Method for Water-Sensitivity Damage
Authors: Yang Renfeng , Jiang Ruizhong 
Published: April 2017

Abstract
The possibility that the productivity is seriously reduced if the producing formation is exposed to the fresh water has been recognized for many years. Many experiments and theoretical studies have been carried out to elucidate the mechanism of water sensitivity. Despite years of field observations and laboratory research, methods of predicting quantitatively the susceptibility of formation to water-sensitivity have not been developed to complete reliability. Until now, there was no model to predict the productivity decreasing according to the experiment results except time consuming simulation.
Based on the latest researches on water sensitivity characteristics and mechanism, core experiments were set up to analyze the permeability and relative permeability parameters changing along with the salinity decreasing under different reservoir properties. Based on material balance equation, analytical function of relative permeability, Backley Leverett theory and Welge equation, a new productivity decline model which can quantitatively predict water sensitivity influence is derived with all the coefficients clearly. The new model has been proven to accurately predict the production performance. The changing coefficients could be obtained through analyzing permeability loss and relative permeability changes through laboratory measurements.
The most significant innovation is that the production performance could be quantitatively predicted rely on the laboratory results. It can be concluded from experiment analysis that the permeability loss was slow after the first fast, and the relative permeability parameters also changed (residual oil saturation and irreducible water saturation becomes bigger, and the relative permeability of both oil and water phase becomes smaller at the same water saturation) along with salinity decreasing because of the clay swelling and the colloidal clay particles captured at a local pore constriction. Then the change of the coefficients in new model could be calculated and the production performance could be predicted. The proposed model has been tested using production data from several reservoirs and the results have demonstrated that the proposed new model works satisfactorily.
The novelty of the new dynamics model is in the ability to solve the production prediction approach for water-sensitive reservoirs according to experiment measurements without time consuming simulation.
Numerical Simulation of Water and Sand Blowout When Drilling through Shallow Water Flow Sediments during Deepwater Drilling
Authors: Gong Zhiwu , Ren Shaoran , Zhang Liang , Zhang Panfeng , Xu Yan , Yu Lu 
Published: April 2017

Abstract
A geological model of typical shallow water flow (SWF) sediment in deepwater basins is constructed based on its basic characteristics, and a reservoir simulation model is then established that incorporates two-phase flow as the basis for the simulation of water and sand blowout process during penetrating SWF formations. The model assumes that sands can start flowing along with water at a critical pressure difference when drilling through SWF formations. The cumulative water and sand blowout as SWF formations are penetrated are calculated and the influencing factors, such as SWF zone size, overpressure factor of SWF formations and penetration rate, are incorporated into the model to quantitatively analyze their impacts on the water and sand blowout from SWF zones. The data are useful for the assessment of the severity of SWF hazards. The results show that the cumulative water blowout and sand blowout will be as high as 100m3 and 1m3, respectively, when a typical SWF sediment is totally penetrated. SWF formation overpressure factor has a remarkable effect on SWF blowout, while SWF zone size has more moderate effects. However, the effects of SWF sediment size are expected to become increasingly significant as time proceeds. 10% increase of overpressure factor of SWF formation will result in around 90% increase of cumulative water blowout and 150% increase of cumulative sand blowout after the SWF zone is totally penetrated, while 10% increase of SWF zone size will lead to about 20% elevation of cumulative water blowout and 25% ascending of cumulative sand blowout. The water and sand blowout can be effectively reduced while increasing the penetration rate, which indicates that elevating the penetration rate can be a useful measure for the control of SWF hazards during deepwater drilling operations.
Heavy Lift Dynamics, Sewol Ferry Offshore Salvage
Authors: Stewart W. P. , George P. , Ashley W. , Guha A. , Achanta V. 
Published: April 2017

Abstract
The Sewol Ferry sank off Korea in 2014 with the loss of 304 lives. The remains of 9 victims remain within wreck and cannot be reached by divers. This paper describes some of the heavy lift engineering involved in the salvage of the 146-meter long ferry, in one piece, from a depth of 44 meters in the ocean, resting on its port side.
A method for calculating the interaction of the vessel stern with the seabed (ground reaction) is described as the bow of the 8,000-ton vessel is raised to place lifting beams to be used in the side lift.
Significant difficulties, associated with geotechnical issues, resulting in project delays are descried.
Calculation methods are presented for determining the large trapped water mass and the large frequency and depth dependent added mass of the submerged vessel (greater than 120,000 tons). Coupled dynamic time domain simulations of the initial bow lift, followed by the side lift onto a floating vessel are presented. A total of 34 HMPE synthetic slings are used to attach a 1,200-ton purpose-built lifting frame to the ZPMC 12,000-ton revolving crane.
Wave forecast data from three sources are compared with continuously measured data from a directional wave buoy at the site. The difficulties in predicting and controlling the heel of the vessel with a combination of added buoyancy, slings and geotechnical forces are described for the failed attempt at the first bow lift and for the final bow lift. Dynamic sling tensions are shown calculated for the upper HMPE slings and the lower steel rope vertical and balance slings from the lifting frame to the lifting beams. Detailed static and quasi-dynamic FEA results are described for the Sewol hull, together with buckling checks.