bluuebunny/crossref_metadata_2025_split huggingface dataset:
SS: HPHT Technology Verification, Validation, and Regulatory Requirements: HPHT Riser Technology Challenges
Authors: Dincal Selcuk , Reagen Daniel , Saglar Nuri 
Published: April 2018

Abstract
Operators are looking to drill and develop deep-water wells with pressures over 15,000 psi and temperatures exceeding 300°F. Designing for high pressure, high temperature (HPHT) conditions present a number of engineering challenges, which can push conventional subsea technology designs to their limits. Therefore, there is a need to understand the feasibility of riser systems in these conditions and consequently to close any potential gaps between the current qualified technology and the outlined project specifications for a number of key riser components.
For conventional reservoirs, the merits of using wet tree and dry tree systems are well understood after years of design, fabrication, installation and operating experience. For HPHT riser applications, various design challenges exist with respect to the technology readiness of various riser system components of a wet or dry tree system development.
Key riser design issues and technology challenges, applicable to wet and dry tree HPHT systems, are addressed in this paper.
For a wet tree development, HPHT conditions require the use of thick wall pipes driven by burst sizing requirements, which in turn will lead to challenges associated with fabrication of pipes, pipe welding and inspection as well as meeting applicable sour service requirements. Furthermore, design of riser hang-off systems of wet tree applications is a critical area that requires consideration. The use of High-Integrity Pressure Protection Systems (HIPPS) to overcome HPHT obstacles is also discussed in this paper.
The use of high strength steel pipe with threaded mechanical connections provides a weight benefit for a dry tree system. However, the qualification of connectors is required and is expected to be a critical activity. In addition, the dry tree system has many other sealing surfaces and connections subject to HPHT loads at the surface and subsea wellhead locations, each of which presents their own design and qualification challenges.
A Multi-Disciplinary Approach to Select the Optimum Infill-Well Location for Efficient Reservoir Management of a Mature Field
Authors: Bose S. , Alzahabi A. , Balasubramanian S. , Chen P. , Thakur G. C. 
Published: April 2018

Abstract
A Multi-Disciplinary Approach (MDA), combining geological characterization, various reservoir property data and production behavior of offset wells, was applied to an unconsolidated sand reservoir to review proposed drilling locations and recommend an optimal well location for improved recovery and effective Reservoir Management (RM). This paper presents a case study where integrated subsurface analysis saved reservoir damage and multi-million dollars in drilling expense, by avoiding a previously approved horizontal well location and selecting an appropriate drilling location.
Seismic amplitude anomalies were investigated by integrating with well-cross-sections along the neighboring wells. Geological and petrophysical information, such as, structure maps, log character, reservoir thickness, sand distribution, NTG, porosity, hydrocarbon pore volume, proximity to gas cap or water zone, and fluid-flow conduits, were analyzed to characterize the reservoir zone, which is contributing to well production.
Interference among the wells was studied in detail for an optimal development strategy. Bubble maps (based on cumulative production plot), well performance analysis, distance between wells and reserve evaluation based on field data were investigated to arrive at an informed decision regarding infill location. In addition, the well history and reservoir characterization were reviewed in detail and integrated with the production analysis.
Integrated analyses using the geological maps and production data showed that higher production correlates directly to the higher pore volume and permeability areas of the maps. The results included show that rock quality is as important as the hydrocarbon saturations in contributing to the production of the field. The reservoir quality maps, fluid contacts, and fault framework helped significantly to identify the higher risks associated with the proposed location. It was recommended to not drill at this high-risk location, contributing to a significant saving of multi-million dollars in Capex. The significant savings in Capex made from the recommendation to not drill the high risk location was helpful to plan a replacement drilling location based on integrated subsurface analysis.
Optimizing Existing Subsea Assets for Respudding of Wells: Step-Over Jumper
Authors: Mercer T. , Williams J. , Roberts J. , Robichaux S. , Flakes K. 
Published: April 2018

Abstract
In the current market, operators are exploring the potential opportunities to optimize the production of existing assets. The goal was to tie a respudded well into existing field architecture, with minimum equipment, time, and cost. The operator respudded a cluster manifold well approximately 50 meters from the tie-in manifold. At roughly twice the distance of the existing well jumper, this approach posed a challenge for a traditional vertical in-plane jumper.
A study was completed to compare a few traditional approaches. The options considered werea 50-meter-long jumper able to reach from existing manifold to the new subsea treea tie-in skid with a flow loop supported by a mud mat and two approximately 25-meter-long jumpersa tie-in skid with a flow loop supported by the abandoned wellhead from the replaced treea step-over jumper (SOJ) supported by a suction pilea SOJ supported by the abandoned wellhead.
Evaluation concluded that the last option was the most cost-effective solution, with 60% capex savings when compared with the SOJ with a suction pile. The benefit of using the SOJ is that the vessel size can be significantly reduced while minimizing the amount of subsea hardware on the seafloor. Essentially, the SOJ works as an extension of the production jumper. First, the production fluid travels from the subsea tree into a conventional jumper. Then, the production fluid travels through the SOJ, where one end of the SOJ is supported by the abandoned subsea wellhead. Finally, the production fluid travels into the manifold. The SOJ is similar to a conventional half-"M"-shape jumper, which has one outboard hub (connector) at each end. The SOJ, however, replaces one of the connectors with an inboard hub and a step-over module (SOM). The SOM provides a firm connection and an inboard hub interface to connect a conventional jumper. The firm connection is accomplished by landing and attaching the SOM to the plugged and abandoned wellhead. Then, a conventional 25-meter half-"M"-shaped vertical jumper is installed between the tree and the SOM to make the final tie-in to the new respudded well.
This is an opportunity for operators to utilize their existing subsea architecture to accomplish cost-saving ventures in their brownfield assets. The SOJ is an efficient solution that allows tie-ins to respudded wells that are farther away from the core field architecture.
Comparison of ASME and BS-EN Codes on Design by Analysis for Subsea Pipeline Components
Authors: Farahani Kasra , Vosooghi Navid 
Published: April 2018

Abstract
Design by Analysis (DBA) based on nonlinear finite element analysis provides an efficient method to design subsea pipeline components. This approach is widely used in oil and gas industry for subsea pipeline components design and pressure vessels. In contrast to linear analysis and stress linearization/categorization, the nonlinear finite element analysis approach provides a more accurate and efficient design route. The design codes encourage the use of the nonlinear analysis approach especially for components with complex geometry.
In this paper, the Design by Analysis approach of ASME VIII D2 and BS-EN-13445-3 using nonlinear finite element method are compared and discussed. These two codes are widely used standards for design of pipeline components and pressure vessels. The philosophy of both codes is limit state involving load and resistance factors. In this paper, emphasis is given to component design in ultra-deep water condition and its significant effect on design during operational cyclic loads. For comparison purpose, a subsea inline Tee is designed to both codes and subsequently the design outcomes are compared and discussed.
The Process to Provide Effective Decision-Support and Realise Value – Implementing a Global Well Integrity Management Software System
Authors: Smith C. J. B. , Lorwongngam A. , Crabtree A. R. , Smith L. , Lunt G. 
Published: April 2018

After spending four years in a close partnership, an independent E&P operator and a services company collaborated in rolling out a progressive well integrity management methodology across operations in West Africa, North Sea, Gulf of Mexico and onshore USA (conventional and shale) has been delivered using a software framework.
This paper describes the process of how the software was configured and adapted to meet the demands of varied well operations and well production types, while also supporting an objective to deliver a standardized view of well integrity across the organization. The incorporation of consistent practices to support the operator's integrity program, including those laid out in ISO 16530-2[1], "Well integrity for the operational phase," is described. This includes a description of the implementation and the value gained from the incorporation of a well failure model (well failure action matrix) that determines and ranks risk to provide decision-making support for potential well intervention.
Furthermore, this paper discusses the practical challenges of implementing a system of this type and the steps taken to ensure the system was incorporated into the operating plan across a diverse portfolio of well types and operating environments.
The implementation project and its results are described, exploring the key factors that contributed towards its success, including user case examples. The paper discusses future areas that may add further value to the safe operation, reliability and the integrity of the operator's assets.
Data Driven Virtual Sensors for Riser Prognostic Integrity Management
Authors: Sundararaman S. , Thethi R. , Hill M. 
Published: April 2018

AbstractIn-field riser strain or motion monitoring provides direct indication of riser fatigue and strength performance for prognostic integrity management. However, direct riser monitoring in the field has been limited in offshore developments to date with respect to its use as a standard on every floating platform and on every riser system attached to the vessel. This is due to the high perceived capital or operational costs of direct subsea monitoring when deployed on every riser to reliably monitor over the entire service life. Furthermore, monitoring devices are typically installed at practical locations, which may not be at fatigue critical areas. A lack of known response in service can result in qualitative inspection planning, conservative fatigue predictions and reduced asset utilization.Data-driven virtual sensors provide an innovative solution for life of field riser monitoring and predictive inspection planning. The virtual sensor is a machine learning model that calculates stresses in the time domain at the fatigue hot spots and at high stress locations along the riser. The sensor is driven by platform motions and environmental loads that are typically measured in the field. It allows calculation of fatigue in near real-time using time synchronous data. The virtual sensor system can be integrated with a topside or centralized data platform.The vision for the virtual sensor is to train a machine learning model initially with finite element global riser analysis data and subsequently with full scale field data from the riser in service. Data aggregation from a term and deployment limited riser monitoring system is employed to capture system-specific response. This hybrid strategy results in low cost virtual sensors for life of field riser monitoring.This paper describes the motivation, methodology, validation and applications for riser virtual sensors. A framework for the development of a riser system machine learning model is described. Global response data is obtained from a vertical top tensioned riser operating in a water depth of 5,000 ft. Fatigue predictions are compared against the fatigue damage calculated from finite element analysis data.
Geohazard Monitoring – Mind Mapping the Complexity
Authors: Strout James M. , Vanneste Maarten , Forsberg Carl Fredrik , Cauquil Eric , Unterseh Stephan , Byrd Daniel 
Published: April 2018

Abstract
Future exploration and production areas may well lie in complex settings where various geohazards can play a role over the lifetime of the field development. The complexity of this is daunting: it is necessary to understand the fundamental geological drivers, address operational conditions for monitoring and instrumentation (including feasibility), the vulnerabilities at stake, and the range of physical parameters that can – or cannot – be measured.
A versatile and generic strategy for assessing and managing geohazards for the operational lifetime of the field is necessary, and this strategy should be applicable to as wide a scope of geohazards as possible. This complexity has been functionally and graphically represented in a series of interactive mind maps, providing a generic framework for geohazard assessment and management, which through the inclusion of site relevant details may be reduced to site-specific tools for geohazard applications.
However, it is also necessary to acknowledge that a suitable system for a given development will always remain site-specific as it must consider the actual geohazards at the site.
The Underwater Intervention Drone, A New Method for Delivering IRM Services in the Subsea Environment
Authors: Jamieson Jim , Wilson Lee , Sherry Wayne , Main William , Solheimsnes Pål Atle 
Published: April 2018

Abstract
Inspection Repair and Maintenance (IRM) services have traditionally in the subsea environment been vessel based relying on remotely operated vehicles (ROV) or Diver operations. The global industry challenge to reduce costs has driven incremental savings; increasing inspection intervals, optimizing the supply chain and contracting methods. Continuing to identify significant incremental savings is not sustainable in the long-term; a more innovative approach is required that eliminates the need for the support vessel, whilst managing the risk in continued operations. Statoil engaged i-Tech Services, a Subsea 7 company, to investigate and report on the use of an underwater vehicle system concept to deliver a new method of providing field wide IRM services. The concept and investigation named as "Underwater Intervention Drone" (UID®) study.
This paper presents a description of the UID® approach to IRM, the equipment needed and the technologies (both existing and to be developed) required to make this concept operationally feasible. For Statoil, the Snorre Expansion Project (SEP), a future field in the North Sea has been selected as the Pilot for the UID® system. An overview of the specific deployment method and services provided by the infrastructure to support the UID® will also be commented upon.
The UID® is a new way of providing IRM services, driven by Statoil to reduce cost and CO2 emission while maintaining a high level of IRM service capability. The UID® encompasses Statoil's and many of the current industry drivers Cost reduction, Digitisation and reduced Environmental impact.
Digital Well Planning - New Cost Saving Well Construction and Life Cycle Well Integrity Model
Authors: Brechan B. , Dale S. I. , Sangesland S. 
Published: April 2018

Abstract
A new generation software for well construction and maintenance is under development. The working name is Life Cycle Well Integrity Model (LCWIM) as its main focus is to support work with wells and fields from the planning stage to final P&A. LCWIM is a systematization of a fully digitalized software model that can provide many advantages for the industry. This paper focusses on four main objectives: Firstly, reduction of workload and direct human involvement by replacing many tasks in well construction and well integrity engineering by automatization. The goal is to shift the focus of humans towards supervision of computerized processes. Secondly, a modern software architecture should provide a fluent interlink between all stakeholders to provide and share information. A fully digitalized module should reduce repetitive tasks. Building on the architecture and metadata of LCWIM, future digitalization projects in e.g. administrative routines such as invoicing can be linked to establish a work process dominated by computerized events which are supervised by humans. Thirdly, the model will store all relevant data pertaining to a well through its life cycle, providing a potent self-service information hub that is easy to use for all disciplines. Fourthly, the scope of the LCWIM is to improve HSE and significantly reduce non-productive time in three ways: (1) interactive experience transfer, (2) embedding of interactive standards and governing documentation to support planning and operation, (3) elevation of personnel out of direct involvement into a supervisory role to reduce human error.
Access and availability favours a cloud based solution. With increasingly more data and information to process, a modern software will require significant processor capacity that is scalable according to the number of users. By combining the capacity of both servers and local computers, the software can provide advanced calculations and graphical representations at interactive response times.
Alcohol Ethoxylate Nano Surfactant: Surface Tension and Compatibility with Acidizing Additives
Authors: Omar Abdulrahman Bin , Alawani Nadrah , Al Moajil Abdullah , Aldarweesh Sajjad 
Published: April 2018

Abstract
Alcohol ethoxylate-based nanosurfactant was experimentally assessed to be used in HCl acid-based stimulation recipes. The surface tension of the surfactant with different stimulation additives was compared with commonly-used linear and branched alcohol ethoxylate-based surfactants. Nanosurfactant showed the lowest CMC of 2 gpt compared to 3 and 5 gpt for branched and linear alcohol ethoxylate-based surfactants, respectively at 77°F. The Nanosurfactant illustrated the highest performance in lowering the surface tension of water to 17 dynes/cm at 280°F. Spent 20 wt% HCl acid and mutual solvent affected the performance of nanosurfactant by increasing the surface tension at temperatures up to 300°F. Live 20 wt% HCl acid showed insignificant effect on the performance of nanosurfactant. Despite the negative interactions with number of stimulation additives, nanosurfactant showed superior surface tension lowering abilities compared to linear and branched alcohol ethoxylate-based surfactants.
Experimental and Computational Study of Thermodynamic Hydrate Inhibitor Mixing and Displacement in Subsea Jumper
Authors: Lu Haidan , Tracy Noah , Johnson SC , Volk Micheal , Delle-Case Emmanuel , Ozbayoglu Evren M. 
Published: April 2018

Abstract
The risk of gas hydrate formation is one of the major concerns for offshore flow assurance. Solutions of methanol (MeOH) and mono-ethylene-glycol (MEG) are most often employed as thermodynamic inhibitors (THI) to prevent the formation of hydrate plugs. This study involves experimental and modeling work to investigate and compare the suitability and effectiveness of methanol and MEG on inhibiting and displacing the water in jumper type configurations during flushing procedures. Numerical analysis aims to investigate the mixing and displacing mechanisms that occur during jumper flushing to optimize key factors such as the position of the injection port and the flowrate of a required chemical inhibitor.
This paper presents the experimental results with respect to effect of inhibitor type, injection rate, brine salinity and liquid loading. All experiments were carried out in a 3" jumper system at The University of Tulsa. Simulations using 1D transient multiphase flow simulator were conducted to evaluate its capacity to predict the thermodynamic inhibitor dispersion by using the inhibitor tracking module. The 3D computational fluid dynamic (CFD) simulations were performed with the commercial software to help predict the amount and flowrates of chemicals required, and to serve optimizing the location of injection ports. Comparisons were made between the simulation results and experimental data from full fresh water loading jumper displacement tests with MEG and methanol.
From the experiments, several conclusions are drawn. Different dispersion and partitioning mechanisms were observed for methanol and MEG through experiments, especially in the vertical sections and low spots of the jumper. Methanol overriding the water phase at horizontal low spots was captured for the low velocity experimental cases, leaving a large amount of water behind that could result in under-inhibited situations. For the 12% brine tests, less water was displaced for each MEG injection rate, whereas a better mixing of methanol with brine was measured. The 1D and 3D simulations provided reasonable prediction for THI distribution along the jumper after displacement tests, except that neither was able to reproduce methanol overriding the water phase at both low spots. 3D CFD simulations results obtained generally gave better agreement with the results from the experiment.
This study provides a better understanding of the displacement and mixing mechanisms of thermodynamic hydrate inhibitors. It helps operators minimize operational risks, reducing the size of the umbilical and decreasing capital costs related to equipment and chemicals.
The Challenges Facing the Industry in Offshore Facility Decommissioning on the California Coast
Authors: Byrd Robert C. , Smith John B. , Spease Steven J. 
Published: April 2018

Abstract
This paper addresses the challenges of decommissioning oil and gas facilities offshore California, where there are a number of large, deep-water platforms, and decommissioning infrastructure and services are severely lacking. The regulatory process for decommissioning platforms is also very complex and expensive and the prospects for reefing platform jackets are uncertain at best. These circumstances have created a situation that the domestic oil and gas industry has not really faced before, i.e., that the cost risk may not be determinate. This will pose a major challenge to decommissioning project management. The paper addresses the major issues and attempts to put boundaries on the cost risk.