bluuebunny/crossref_metadata_2025_split huggingface dataset:
Qualification of Biopolymer in Offshore Single Well Test
Authors: Urkedal H. , Selle O. M. , Seime O. J. , Brandal Ø. , Grøstad T. , Todosijevic A. , Dillen M. , Prasad D. , Ernst B. , Lehr F. , Mahler E. 
Published: October 2017

A single well polymer injection and back-production test has been performed at Heidrun, an offshore oil and gas field in Norway. The objective of the test was to verify at field conditions the properties measured in the laboratory for the biopolymer Schizophyllan. This test was part of a polymer qualification program. This paper will give an overview of the single well test and lessons learned.
To ensure high quality data from the test, all elements in the test required detailed planning and following up, including an extensive quality check. The successful execution of the test was possible through a joint active collaboration between the operator, the biopolymer supplier and the service providers. The first focus was on the logistical chain from production of biopolymer, transportation and quality checking prior to injection. The second focus was on the injection, including qualifying polymer mixing equipment for offshore use and preparation for using an injector for both injection and back-production. The third focus was on sampling and analysis where high quality sampling and analysis was a prerequisite for getting conclusive results.
The test was an operational success with no HSE incidents and delivery of an extensive data set, including pressure, temperature and flowrate data as well as of fluid samples. A total of 3,500 m3 of polymer solution including biocide was injected as planned, followed by a short back-production period of 195 m3 for baseline sampling. The remaining polymer solution was shut-in for 39 days before final back-production of 365 m3. Both during injection and back-production samples were taken for later analysis and evaluation of results.
The data confirms that the biopolymer is not being biodegraded during the shut-in period due to efficient application of the biocide injected simultaneously with the biopolymer. The rate and pressure data also supports that the injectivity is maintained during the test compared to water injectivity.
The Effectiveness of the Infraction Notice as a Tool of the Regulation System
Authors: Saad H. C. , Bergamaschi M. B. , Tavares G. R. , Santos M. D. 
Published: October 2017

Abstract
This paper aims to discuss the role of the National Agency of Petroleum, Natural Gas and Biofuels (ANP) in the inspection of fluid measurements, and to present a history of improvement of the issuance of infraction notices, related to the violation of the current resolutions, in addition to their sanctioning implications to regulated agents. In order to carry out this study, the data of all infraction notices issued by the Nucleus of Insspection of Measurement of Petroleum and Natural Gas Production (NFP) from 2010 to 2015 were analyzed, showing the process of finding nonconformities on the measurement systems and how infraction's amount is calculated. In addition, the results of court judgments will be present and, finally, a comparison between the number of infraction notice issued, the infraction committed and the punitive pedagogical implications applied. Futhermore after a critical analysus of each infraction notice issued and its respective nonconmities, it is observed that the most common infraction is the divergence between the values declared in the Daily Production Report and those recorded in the flow computer of the measurement system monitored by NFP. These and other infraction notices generate financial penalties whose are set to force operators to follow the recommendation given by ANP. Petrobras, which is responsible for 94.3% of oil and gas production in Brazil, awsers for most part of infraction notices issued and has paied approximately R$250 million.
New Fiber Technology to Improve Mud Removal
Authors: Engelke B. , Petersen D. , Moretti F. , Halla L. A. , Becker R. , Pagani L. , Revilla R. A. , Martinez A. 
Published: October 2017

Abstract
As drilling muds evolve to satisfy well requirements, cementing preflush technologies need to change to ensure proper mud removal during cementing jobs. A new component—engineering-designed fiber—was added to a preflush fluid and tested in the laboratory, with promising results. The system was then implemented in Latin America.
Obtaining proper mud removal is very important for achieving zonal isolation at cementing jobs. The new technology consists of the addition of an engineering-designed fiber to cementing preflush fluids to significantly improve the removal of nonaqueous fluids from the well during cementing operations. The fibers are compatible with both cement slurries and mud. They work by removing the mud from the casing or formation through two mechanisms: by mechanical cleaning and by attracting the nonaqueous compound of the mud toward itself by hydrophobic-hydrophobic interaction. Two different methodologies were used to evaluate the fiber's ability to enhance the chemical wash and spacer capabilities to clean and demulsificate the nonaqueous mud fluids.
The laboratory tests were performed with cementing preflush fluids with and without the fibers. Results indicated that the preflushes with the fibers were able to clean and demulsificate the drilling mud much more efficiently than preflush without the fibers. Indeed, it was possible to optimize the amount of the preflush surfactants and still obtain excellent results. Some successful cases of field implementation of this technology corroborated the laboratory findings. In both cementing jobs, results indicated very efficient mud removal, and, consequently, zonal isolation and well integrity were achieved.
The fibers were successfully pumped in a field in Latin America. This innovative technology is able to enhance cement bonding in both casing and formation and reduces potential remedial job costs in a wide range of challenging environments.
Development of Low-Manganese L80 HF-ERW Tube Containing 1%Cr with Addition of Boron
Authors: Melo L. C. R. , Cordeiro W. R. , Gomes I. O. , Ferreira M. W. , Filho J. C. Payão 
Published: October 2017

Abstract
The purpose of this work is to present the development of low-manganese pipes containing 1% Cr and Boron manufactured by the HF-ERW process according to standard API SPEC 5CT (2011) L80 grade. The study has an innovative character and the main competitive advantage is the relatively low cost of manufacturing combined with the high level of quality in welding process and subsequent heat treatment of quenching and tempering.
The chemical composition of the steel was designed in such a way to ensure good weldability, high hardenability and low mechanical properties variation after tempering. Low levels of Manganese was established and increase the resistance of hydrogen induced cracking due the tendency of formation of MnS inclusions in the continuous casting. Additionally, levels of 1%Cr were incorporated to ensure corrosion resistance in water injection wells. Hollomon model was used to set the tempering temperature as a function of the aim mechanical property. To characterize the tube, the follow tests were performed, tensile, Charpy, hardness, microhardness, optical microscopy, SEM and CO2 corrosion tests.
The seam weld presented excellent results under UT inspection. The low variability in the mechanical properties shows that the quench and tempering process was stable, which is able to meet the API SPEC 5CT (2011) L80 grade and NACE MR0175 (2003). The scanning electron microscopy identified fine precipitates dispersed in a martensitic matrix, this being the mechanism of secondary hardening which raised the tempering temperature as provided by Hollomon model. The corrosion resistance was compared with N80 and confirmed more than 75% resistance according to the references.
In view of the results we conclude that the low manganese tube containing 1%Cr manufactured by the process HF-ERW meets the requirements of Standard API SPEC 5CT (2011) L80 grade and thereby contribute significantly in increasing competitiveness in the oil and gas production, mainly for the water injection wells by increasing corrosion resistance and offering a tube manufactured by a competitive process compared to seamless.
An All-Electric BOP Control System: A Game-Changing Technology
Authors: Dale John , Rød Magne , Howes Thomas 
Published: October 2017

Abstract
Control system failures in subsea operations are a leading cause of Blowout Preventer (BOP) down-time. The cost of these failures can increase exponentially with water depth. Legacy BOP control systems are based on 90-year-old hydraulics technology and have been stretched to cope with new regulatory requirements and harsher environments. The industry has responded to these design requirements by increasing component sizes, weights, and system complexities. These adaptations have resulted in unintended consequences, such as reduced reliability and an increase in wellhead loading. As subsea operations move into deeper water and wellhead pressures increase above 15,000 psi, legacy control systems may have reached their design limit. This paper introduces a new concept of an all-electric BOP, a game-changing technology that will not only negate these issues, but also improve the safety, efficiency, reliability, and functionality of subsea BOP control systems.
A Novel Approach to Reliability Qualification Testing: Key Constituent in Successful Development of Electrohydraulic Flow Control Device
Authors: Balasubramanian Aswin , Gissler Bob , Shrivastava Pankaj , Saldanha Savio 
Published: October 2017

Abstract
Flow control devices (FCD) play a vital role in an intelligent completion’s ability to enhance reservoir management capabilities by allowing the operator to control inflow and outflowremotely. Among FCDs, the most versatile type is electrohydraulic. However, because these electrohydraulic FCDs are permanently installed in severe downhole conditions, it is important to integrate the reliability qualification testing (RQT) in the overall development effort. This paper describes a novel approach to product development which integrates RQT as a key component.
RQT incorporates testing for all criteria, including function, environment, and reliability. It typically includes accelerated testing, which is performed to reduce testing time while helping ensure product reliability is verified. RQT is applied in the form of a systematic, streamlined, and concurrent verification program to help improve the reliability of the product. Design for reliability (DFR) tools, such as FMEA (failure mode and effects analysis), help identify the key failure modes and failure mechanisms (causes of failure) related to the product. It is of utmost importance to understand these failure mechanisms in detail and correlate them to the stresses applied during testing.
RQT planning uses the analyses performed during the design phase, such as FMEA, reliability predictions anddevelopmenttesting results, to highlight the risks associated with the product. And, further integrates this information to efficiently design the tests. The primaryobjective of RQT is to determine whether the product will meet the mission reliability target. RQT planning not only identifies the need for component reliability testing, but also substantiates reliability targets at the component level. Multiple ingredientsare required todevelop an efficient RQT, such as (a) performing risk-mitigation studies during design phase, (b) defining a mission reliability target at the system and component level, (c) addressing the range of environmental conditions, (d) using accelerated test plans, (e) optimizing test parameters, sample size, test time, etc.
This paper presents an efficient RQT plan, developed for FCD, as well as all associated accelerated testing models for system reliability predictionsand statistical confidence. Also discussed is a uniqueapproach for identifying and integrating key elements of a holistic RQT, which can be used to design an efficient test plan. This approach unites the reliability studies performed during development stages, and further, uses accelerated testing for successful product development, resulting in both cost and time-to-market improvements.
OTIMROTA-Multiline: Computational Tool for the Conceptual Design of Subsea Production Systems
Authors: Fonseca dos Santos Thiago Duarte , Rocha Djalene Maria , Pereira Ladislau Israel , Baioco Juliana Souza , Albrecht Carl Horst , Jacob Breno Pinheiro 
Published: October 2017

Abstract
This article presents a computational tool oriented to develop subsea layouts of oil production system focused on design concepts associated with wet completion. The OTIMROTA-Multiline has been developed by Petrobras in partnership with UFRJ; its goal is to comply with the needs and requirements to develop conceptual design of several subsea systems currently being studied in the Brazilian pre-salt scenarios.
Considering that subsea projects are intrinsically complex, multidisciplinary and comprising of several interfaces, the OTIMROTA-Multiline tool follows two approaches to achieve an optimal solution. The first is based on deterministic methodologies, intended to systematically reproduce design experience with logical restrictions; thus, a large number of candidate solutions can be quickly analyzed, greatly reducing the time to complete the design. The second approach is based on evolutionary algorithms such as Genetic Algorithms to solve the optimization aspects. Both approaches have a large search space, with several interdependent design variables, with complex and quite unpredictable interactions. The final goal is to reduce the overall project costs.
Initially, the computational tool includes facilities to find the best position for a floating production unit (FPU), and to interactively integrate satellite wells in an optimized subsea layout. Compliance with the many design criteria, parameters and requirements is automatically checked, including marine geology and environmental constraints; pre-existent obstacles; simultaneity of offshore operations; risers anchoring, and so on.
Information is available to the designer throughout the tool iterative execution, including acquisition and installation costs for the equipment and flowlines, and expected oil flow rates for each candidate solution. As a final deliverable, the tool automatically provides a formatted report with all relevant results for a proper project selection. The tool also exports a file that can be employed in 2D/3D modeling programs, enabling the best alternative selected to be subsequently detailed by the specialists.
One of the main contributions of developed automation tool will be to enhance the integration among the technical teams through less complex analyses; this will contribute to a more reliable and robust alternative selection, leading to more efficient solutions.
Further developments are currently underway, including new subsea architectures (including production ring, trunkline, manifolds), along with their costs, production flow modeling and the interface with well and topside design to have a more robust tool for evaluation of new architectures.
Geomechanical Model and Wellbore Stability Analysis of Brazil's Pre-Salt Carbonates, a Case Study in Block BMS-8
Authors: Silva Cristiane , Rabe Claudio , Fontoura Sergio 
Published: October 2017

Abstract
In this study, a wellbore stability model was built of the pre-salt area using analytical correlations to obtain an optimum mud window. The operational window assists in optimizing the fluid weight to be used while drilling and is defined by a lower limit (pore or collapse pressure) and an upper limit (fracture gradient). To build a geomechanical model, it is necessary to estimate different parameters. Log data from offset wells, pressure measurements, formation integrity tests, and data from the World Stress Map were used to estimate overburden, pore pressure, rock strength, the magnitude of the minimum horizontal stress, and the magnitude and direction of the maximum horizontal stress. These parameters made it possible to estimate the collapse gradient and define the mud window. The sensitivity analysis of the parameters was performed on the rock strength (UCS) and maximum horizontal stress due to the lack of available data, especially borehole images, 4 to 6 arm caliper, and triaxial tests. The geomechanical model indicates that the overburden in the carbonates of the studied area ranges from 14.0 to 14.6 lb/gal. Pore pressure indicates two different behaviors, presenting slightly over-pressurized (approximately 9.4lb/gal) and over-pressurized in another area (13.2lb/gal). The results of the formation integrity test (leak-off tests) were used to estimate the minimum effective stress ratio (ESRmin), a constant value around 0.65 with a minimum horizontal stress values between 12.4 to 12.6lb/gal in the slightly over-pressured zone and in the over-pressured zone the values are between 13.8 to 13.9lb/gal. The average value of uniaxial compressive strength (UCS) was estimated at approximately 43MPa. The azimuth of maximum horizontal stress was estimated to be approximately 95° and was obtained from the World Stress Map. The effective maximum horizontal stress ratio (ESRmax) was between 0.95 and 1.45, according to the presented scenarios, and the conclusion was that the faulting stress regime was between normal and strike-slip. For the mud window calculation, the effects of slightly over-pressured pore pressure (Pp) and the selected failure criterion, elastic properties and allowable breakouts provided a lower bound limit to the mud window in the carbonates of between 10.0 to 10.1lb/gal and an upper bound limit between 12.4 to 12.6lb/gal for the study area. In the zone with the high-pore pressure gradient, the geomechanical model provided a lower bound limit between 13.3 to 13.4lb/gal and an upper bound limit between 13.8 to 13.9lb/gal.
Parametric Study of the Influence of GOR and CO2 Content on the Simulation of a Pre-Salt Field Configuration
Authors: Pasqualette M. A. , Rempto M. J. , Carneiro J. N. E. , Fonseca R. , Ciambelli J. R. P. , Johansen S. T. , Løvfall B. T. 
Published: October 2017

Abstract
A distinct characteristic of reservoir fluids in different Brazilian pre-salt fields is the high Gas-Oil- Ratio (GOR) and high content of CO2 in the associated gas. In particular, the presence of CO2 in significant amounts is known to have a strong influence on the thermophysical properties and phase equilibria of the oil mixtures. Due to the strategy of re-injection of CO2-rich streams for EOR purposes, these aspects can be even more pronounced in the production fluids in future scenarios. In the present work, a parametric study is performed to investigate the influence of both CO2 molar content and GOR, in a controlled manner, on the simulations of a pre-salt field configuration for various operating conditions. PVT look-up tables were used with a commercial multiphase flow simulator.
First, the thermodynamic modelling of a 20% molar CO2 pre-salt oil was performed, along with well characterized CO2-live oil mixtures taken from the literature, in order to generate PVT look-up tables. They were used to successfully reproduce field data and assess the validity of multiphase flow simulation results from a commercial software. For the CO2-rich live oil mixtures from the literature, a parametric study was performed in which the CO2 molar content ranged from 20% to 50% with 300-600 Sm3/Sm3 of GOR. Simulation results of temperature, total pressure drop, gas volume fraction and gas- liquid density ratio are presented and compared.
Dynamic Model for Production Optimization to Offshore Platforms with Short-Time Machine Failures
Authors: Vieira B. F. , Rosa V. R. , Arraes F. F. , Teixeira A. F. 
Published: October 2017

Abstract
The objective of this paper is to give a support decision tool to help the engineer when main equipments, especially compressors, fail for a short-period, that is to say, a few hours. This is a very complex problem since, according to the transient period of the wells, an intertemporal component is included. Until a steady state is reached again the operator must decide every period (typically every hour or every half an hour) on which wells to close or open, how much gas lift should be injected, how much the chokes should open or close in order to maximize oil production.
On the Hydrodynamic Aspects of the Carbonate Scale Formation Process in High Flow Rate Wells
Authors: Maciel R. S. , Cosmo R. P. , Maciel F. S. , Pereira F. A. R. , Ribeiro D. C. , Aldeia Santo W. , Martins A. L. 
Published: October 2017

Abstract
Easily accessible oil deposits are increasingly scarce, and therefore, more challenging reserves will require innovative solutions and technologies. Carbonate reservoirs are today important resources to be developed. Among the challenges imposed to the flow assurance process, the thermodynamic envelopes for scale formation have been widely studied. This article deals with the additional aspects related to the hydrodynamics of saline scaling of carbonate origin, noticeably calcite. Several phenomena before scaling and should be considered in a global simulation. The forecast of scaling only will represent the reality if all relevant phenomena are accurately described. In this sense, the dynamic growth of calcite crystals influenced by the fluid flow dynamics were investigated using experimental and computational fluid dynamics (CFD) techniques. Experimental data were obtained to evaluate the solid particle size distribution, and these profiles, were the boundary conditions of a discrete phase modeling. The experimental data, coupled with CFD could estimate the scaling rates at high flow rates production wells. The coupling technique constitutes novel contribution to the understanding of carbonate scaling phenomena and can be used to support field procedures for its mitigation, avoiding production losses.
Wax Removal Procedure Used in Pre-Salt Oil Well
Authors: Andreotti Thiago , Neto José Alberto Rodini , Lorenzeti Jorge Fernando Canato 
Published: October 2017

Abstract
This paper presents a real case of wax deposition in production lines from one Brazil Pre-salt well located at Santos Basin. It also shows a diagnosis of the problem as well as the methods adopted to remove the wax.
An effective wax removal method may imply great costs, not only to implement it but also regarding the production loss involved. The best solution may not always be the one that removes the greatest amount of wax, but the one that implicates lower costs and allows operational continuity.
In order to remove wax from production line, the first method used was pig launching. The second was diesel soaking and the third and final method used was a high velocity viscous flow inducing shear tensions to the walls.
The result of each method allowed us to choose the best one regarding: production continuity, cost and wax removal effectiveness. It was possible to identify that the approach of pig launching was not effective enough. The diesel soaking approach had better result than the pigging, but generated higher costs due to the great length of the production line (9 km). The high velocity viscous flow method was the approach that gave the best results, concerning not only the amount of wax removed but also the reduced "closed well time" and costs. Repeating the high velocity viscous flow approach allowed us to optimize operation total time and the diesel consumption to perform it. The greatest conclusion was to find a method to prevent complete blockage of the production line without wasting long time of well production.
Once this was the first well from Santos Pre-salt to present wax deposition issues, this paper is an important report of good practice in dealing with such a problem.