bluuebunny/crossref_metadata_2025 huggingface dataset:
Discovery of New Oil Reserves by Combining Production Logging with Open Hole Log Interpretation in Low Resistivity Pay
Authors: Shi Xinlei , Wang Peichun , Xu Jinxiu , Yang Hongwei , Xu Sainan
Published: April 2020

In this paper, we examine the evaluation of a low resistivity pay siliciclastic reservoir in Bohai Bay, China. The reservoir consists of fine to silt sized sand grains with dispersed illite and smectite minerals filling the pore throats. Due to the large surface area associated with the small grains and the clay minerals, a significant amount of irreducible water is bound to the rock surface, dramatically lowering the resistivity of the pay zone. This phenomenon makes open hole log interpretation quite challenging because pay zone resistivity can sometimes read very close to that in water zone. Wireline formation tester shows oil gradient in sands where open hole logs indicate as wet and shaly. However, these sands were excluded from the initial reserves estimation so that uncertainty is minimized.

In order to confirm hydrocarbon production potential and grow reserves in the low-resistivity sands, the operator perforated these sand intervals and acquired production logs. The borehole fluid density and water holdup from production logs clearly indicate that there's hydrocarbon production coming from the low resistivity zones. Detailed analysis revealed that these sands contribute 46 cubic meters of oil per day with no water production. This result confirms our theory that the low resistivity is caused by bound water trapped in clay minerals. These rocks are actually saturated with oil with almost no free water. Based on this finding, we made a few adjustments to our petrophysics model. We modified the amount of bound water associated with clay so that there's no free water in the zone. Also, we adjusted the parameters used in the shaly sand saturation equation to better account for the conductivity contributed by clay.

With this improved interpretation model, we made production predictions for a few offset wells based on their open hole logs. Additional perforations were added in the low resistivity sands of these wells according to log interpretations. Production history of these wells are highly consistent with our predictions and shows that the low resistivity sands produce good quality oil with almost no water. These newly discovered pay zones increased proven reserves by about 430 thousand tons.

Production logging is typically a production diagnosis tool to improve the understanding of reservoir petrophysics. The novelty of our idea is that we use production logging to provide the ground truth of reservoir fluids in the low resistivity pay and use this information to improve our petrophysics model. The improve model allows us to accurately predict the production from low-resistivity pay sands in other wells, without the need for further production logging.
Experimental Investigation of LNG Underwater Release and Combustion Behavior on Water Surface
Authors: Zhang Yixiang , Zhu Jianlu , Peng Youmei , Song Cunyong , Li Yuxing
Published: April 2020

This work foucs on the safety transportation and risk evaluation of LNG accidental release and vapor cloud flame. The experimental was conducted in water tank with dimension of 1×0.5×0.5 in height × long × width and placed in a wind tunnel. The LNG released from a storage tank which connected by a flexible insulation tube. A stainless steel pipeline placed through the plexiglass tank with three orifice sizes and 0.6 m water depth. The leakage pressure and volume flow rate was measured by a pressure gauge and liquid flow meter with online monitoring. The dynamic behavior of LNG jet release was recorded by a high speed camera from a full and micro view. The flammable vapor was immediately ignited on the water surface under different crosswinds. In addition, a new correlation of the radio between flame height to width with mass loss rate and wind speed has been proposed. The flame temperature was employed by an array of K-type thermalcaplous in vertical and horizontal directions. An infrared camera was used to compare the thermal distribution for quantitative.
Condition Based Monitoring of Pumps Using Machine Learning
Authors: Chakraborty Ishita , Kluk Daniel J
Published: April 2020

A variety of pumps are employed in all aspects of the oilfield life cycle, such as drilling, completion (including hydraulic fracturing), production, and intervention. There is no well-established method to monitor the pump fault states as they are operating based on sensor feedback. As a result, maintenance is performed either prematurely or reactively, both of which result in wasteful downtime and unnecessary expense. A machine learning based neural network model is used for identifying different fault states in a triplex pump from measured pressure sensor data. In a laboratory test, a triplex pump was seeded with eight different fault states (different combinations of damage in discharge valves, stuffing boxes, and suction valves). The time series data for suction and discharge pressures are recorded for 1500 different runs for a combination of eight different fault states and nominal condition. An efficient neural network model is trained on the observed data. This model is tested with multiple cross validation sets and is seen to have over 90% accuracy in predicting the correct fault class solely from the suction and discharge pressure data. In almost all cases, the model was able to correctly differentiate between the nominal response and response with different faults in the system. Different parameter transformation or feature engineering is performed to select optimal input features for the machine learning model. This work demonstrates that machine learning techniques can accurately predict different faults in pumps in operation from monitoring the suction and the discharge pressure. This work also demonstrates the importance using engineering domain knowledge for feature extraction and feature manipulation in creating insightful machine learning models.
Full Wellbore Geohazards; Evolution of Subsurface Hazard Assessments at the Tahiti Field, GOM, USA
Authors: McCarren Heather , Gutenkunst Michele , Ruberg Daniel
Published: April 2020

Chevron has applied an increasingly robust approach to wellbore geohazards assessment over the Tahiti Field life. We discuss here how hazards assessment has evolved over nearly 2 decades. The last ~5 years we have applied a standardized approach to identify conditions of concern and incorporate knowledge gained from previous drilling results. Applying this approach, we have seen communication improvements among the Integrated Drilling Team (IDT). Results of the well-specific assessments assist in providing an informed and improved well design and drilling program. Retrieval of former drilling results though our lookback documentation has similarly seen benefit by employing this approach to documentation of events. Subjectivity of the assigned project team is minimized through the employment of standardized classification criteria. In order to tie-back to the drilling department metrics, we leverage geologic non-productive time coding and actual drilling events to qualify our consequence guidance not just within the Tahiti field but within the Gulf of Mexico Business Unit (GOMBU) and across the enterprise.
Supervised Multi-Agent Autonomy for Cost-Effective Subsea Operations
Authors: Vincent Jack , Vannuffelen Stephane , Ossia Sepand , Speck Andrew , Strunk Gavin , Croux Arnaud , Jarrot Arnaud , Choi Gloria , Osedach Timothy P. , Gelman Andriy , Grall Sebastien , Eudeline Guillaume
Published: April 2020

Service providers for subsea inspection, maintenance, and repair (IMR) generally utilize remotely operated vehicles (ROVs), tethered to a surface vessel and piloted in real-time, to evaluate and manipulate underwater infrastructure. The cost of these operations can be considerable, mostly due to the need to deploy a large surface vessel and crew to support the IMR campaign. Recent progress in marine autonomy, acoustic communication, and artificial intelligence, however, enables new approaches to subsea IMR that could substantially reduce the need for an on-site support vessel and, consequently, the overall cost of these activities. This work describes a novel multi-agent autonomous system comprising an autonomous underwater vehicle (AUV) and unmanned surface vessel (USV). We describe a unique AUV configuration that incorporates a custom high-bandwidth acoustic communication system capable of video transmission to the surface. A state-of-the-art proprietary USV was configured to act as a communication gateway for the AUV, enabling remote mission management from a nearby support vessel. We describe the results of a field test campaign in which real-time video transmission from the AUV was demonstrated at a depth of approximately 900 m. We also describe results from a shallow water test in which the AUV's profiling sonar and integrated lidar system were used to generate 3D maps of a wreck of a World War 2 fighter plane.
LWD Acoustic Application for Cement Bond Evaluation: A Case Study in Brazil
Authors: Bicalho Lorena , Barbosa Ariane , Wu Lei , Salazar Jesus , Rodrigues Augusto
Published: April 2020

Well integrity is very important for well operation in oil and gas industry. Advanced technologies and analyses have been developed to ensure well integrity. One of the most important analysis to be done is the evaluation of the cement bond which measures the presence and bonding of cement between casing and the formation in a particular depth or interval. This evaluation is critical for hydraulic isolation to withstand subsequent completion and production operation.

Usually, Cement bond evaluation is done from wireline logging, with a tool that transmits acoustic waves and compute the acoustic energy propagating through the casing, the cement and the formation. The amplitude and the attenuation of the returned wave can be correlated with Bond Index (BI), due to the difference in acoustic impedance between casing and cement.

Over years, different wireline technologies have been developed and matured for cement bond evaluation. Nowadays, it can be found scenarios where wireline operation is not feasible, such as in highly deviated wells or when a quick turnaround is needed.

Acoustic technology in Logging While Drilling (LWD) has been developed to measure the compressional and shear slowness of the formation. These devices are able to transmit acoustic wave at different frequencies and receive them after propagation through a medium, applicable in cased hole condition. This paper presents a case study where the LWD Acoustic technology was successfully used to evaluate the cement bond in a high deviated well in Brazil and the results show the capabilities of the technology to generate a qualitative cement bond data quality. These results were successfully validated using sonic and ultrasonic wireline technologies. This comparison, between LWD acoustic and wireline results, is shown in this paper, including details of the methodology applied to the test, parameters considered and the data processing.
Human Systems Integration Relationships Between Deep Space and Deepwater Exploration Challenges
Authors: Salazar George , Russi-Vigoya M. Natalia
Published: April 2020

NASA pursuit of human missions Beyond Earth Orbit (BEO) to the moon and eventually Mars will pose many new challenges. These missions are characterized by increased risks to human performance due to stress, fatigue, radiation exposure, and isolation. Fundamental changes in spaceflight operations will be required as well. A very critical part of future missions will be assisting the crew with problem-solving and contingency resolution using next-generation smart spacecraft systems. Human Systems Integration (HSI) must be included as part of the systems engineering process. Gateway1 will serve as part of the proving ground for maturing technology such as autonomous systems and space operations procedures to help meet moon mission goals and prepare humans for missions to Mars. For deep space missions, risk factors affecting humans such as mission duration, distance, and physiological/psychological effects, must be considered. A human is not a simple component but rather a system in a systems-of-systems application-a system influenced by cognitive and biological factors that are difficult to model/analyze. System complexity will demand an integrated approach that requires multiple viewpoints, including the understanding of the astronauts' capabilities and limitations to enhance safety, performance, and satisfaction on the interaction between all system users in a variety of environments to achieve acceptable mission goals and performance. HSI will play a vital role in the development of these future missions. This paper provides a discussion of HSI used at NASA and the critical role human factors engineering will play in the HSI process for future missions along with the challenges. Industries such as oil and gas (O&G) could benefit from the content of this paper to help improve the safety and operations of deepwater/oil and gas exploration activities. NASA engineering and human systems subject-matter expert personnel reviewed challenges reported in space-related environments for long space duration missions and identified similarities with the challenges encountered in deepwater exploration. The researchers noted the space industry's current solutions and proposed a system development view to solve future deepwater exploration challenges using HSI principles. This paper discusses the results of the review.
Intelligent Subsea Condition Monitoring by Digitization and Mining of Big Data
Authors: Ferreira Joel Stephen
Published: April 2020

Inspection Maintenance and Repair activities can typically be reactive in nature, often relying on adequate inspection intervals in addition to Risk Based techniques to minimise production down times.

To compliment current IMR technologies, a suite of Digital Applications is currently being developed to provide operators with additional ‘real time’ remote condition monitoring information. The aim is to provide a focused up-to-date status of subsea equipment and insights on equipment remining life, in the form of both predictive and prescriptive analytics. Combining this information with more traditional inspection techniques will provide a powerful tool in defining support strategies including planning activities to support operations through planned ROV/intervention campaigns, use of remaining life metrics to drive spares holding, location and SIT of spares or use of deep understanding of equipment performance to drive campaign based ROV maintenance activities.

The condition monitoring services and digital suite currently in development will enable, optimisation of operational performance, early identification of system degradation, prediction of equipment failures before they occur (prognostics) and immediate notification of equipment failure.

Although the condition monitoring services and digital suite currently focuses on Subsea Production System Performance, development of an ongoing ‘vulnerability matrix’ with participating operators is providing impetus to broaden the breadth of scope to include process measurands. The goal being to provide a useful suite of focused applications and services which have the potential to significantly improve overall production efficiency tailored to the specific needs of the oil and gas production industry.
Design and Process Optimization for Additive Manufacturing in Oil and Gas Industry
Authors: Acharya Sunil , Zhang Yi , Yang James
Published: April 2020

Recently, Additive Manufacturing (AM) has received a lot of attention as a viable manufacturing process for structural components. For certain applications, this technique brings time-savings and is cost-effective. AM methods offer unique challenges as well as advantages over traditional manufacturing techniques. Simulation-driven product design can address the challenges while exploiting the advantages to optimize components relevant to the Oil and Gas industry. Also, process simulation can be used to qualify the component design for distortion, residual stress, and process parameters Conventional design and design-optimization techniques typically do not apply for AM part design. The flexibility of AM in generating complex shapes implies reduced number of components and implicit savings in assembly. Also, the possibility of lattice structure generation implies that there is potential for light-weighting the component through design. The ability to incorporate these structures broadens the design criteria to achieve previously unforeseen possibilities. Topological optimization, along with Finite Element simulation during the design stage is invaluable to achieve light-weighting of the ship components while meeting structural performance criteria. For products with fluid or electromagnetics applications, Multiphysics optimization is useful to improve part performance. After arriving at the part design, the "print design" needs to be addressed. Here decisions on part orientation, support location, and support design are important. Typically, the AM process involves large thermal transients and phase change. As a result, significant residual stresses appear in the manufactured components. It is important to qualify the part design so that these stresses inherent to the AM process do not lead to mechanical distortion or initiate cracking of the lattice structures. Process simulation is effective in estimating stresses generated in components, distortion, and adequacy of the support design. Use of these simulation techniques during the product and process design reduces the number of trials before part printing compressing the product development cycle.

The presentation will illustrate the simulation methodologies in Multiphysics design and process optimization in different industrial applications. The presentation will conclude with lessons for the Oil and Gas industry.
Experimental Investigation of Biopolymer Rheology and Injectivity in Carbonates
Authors: Elhossary Deena Abdalla , Alameri Waleed , Al-Shalabi Emad W.
Published: April 2020

Polymer flooding is a mature chemical enhanced oil recovery (CEOR) technology with over forty years of laboratory- and field-scale applications. Nevertheless, polymers exhibit poor performance in carbonates due to their complex nature of mixed-to-oil wettability, high temperature, high salinity, and heterogeneity with low permeability. The main objective of this study is to experimentally evaluate the performance of a biopolymer (Scleroglucan) in carbonates under harsh conditions of temperature and salinity. This experimental investigation includes polymer rheological studies as well as polymer injectivity tests. Rheological studies were performed on the biopolymer samples to measure the polymer viscosity as a function of concentration, shear rate, salinity, and temperature. Injectivity characteristics of this biopolymer were also examined through corefloods using high permeability carbonate outcrops. The injectivity tests consisted of two stages of water pre-flush and polymer injection. These tests were conducted using high salinity formation water (167,000 ppm) and seawater (43,000 ppm) at both room (25 °C) and high temperature (90 °C) conditions.

The rheological tests showed that the biopolymer has a high viscosifying power and it exhibits a shear-thinning behavior that is more prevalent at higher polymer concentrations. Also, a pronounced effect was observed for water salinity on both polymer filterability and polymer injectivity. The biopolymer exhibited better filterability at the high temperature as opposed to the room temperature. From the injectivity tests, the shear-thinning behavior of this biopolymer in the porous media was confirmed as the resistance factor decreased with increasing the flow rate applied. The potential biopolymer showed good injectivity at both the room and the high temperatures. This study provides further insight into the performance of this biopolymer in carbonate reservoirs and encourages further application under harsh conditions of salinity and temperature.
Additive Manufacturing in Heat Exchangers and Valves
Authors: Tirelli Valeria
Published: April 2020

This paper will present additively manufactured (AM) metallic solutions and their benefits for various products such as heat exchangers, valves and oil and gas components.

The adoption of Additive Manufacturing can generate many advantages thanks to the reduction of lead time such as fast prototyping, acceleration of R&D, on-time delivery of spare parts. Moreover, it's possible to take profit of Additive Manufacturing in situations that require lightweight, space-saving, complex components and improved performance.

The value chain of additive manufacturing will be shortly analyzed from the design to the production with metal 3D printers, including the non destructive tests and post-processing activities.
Temperature Abatement using Spray Injection and Metal Wire Mesh in Liquid Piston Compressor for Ocean Compressed Air Energy Storage Application
Authors: Ahn Barah , Ro Paul I , Patil Vikram C
Published: April 2020

One of the challenges in designing an Ocean Compressed Air Energy Storage (OCAES) system is achieving efficient compression and expansion of air. The rise of temperature during air compression results in significant loss of energy which leads to low storage efficiency. In this study, temperature abatement in liquid piston compressor using spray injection and metal wire mesh are investigated experimentally to improve storage efficiency. Water spray at different injection pressures and metal wire mesh of different surface areas and volumes were tested for heat dissipation inside the compression chamber. Results indicated that the water spray injection is useful to reduce the final temperature from 334 K to as low as 297 K for compression of air from atmospheric pressure to about 250 KPa when the injection pressure is 60 psi. For the more effective metal wire mesh among the inserts tested in this study, temperature abatement to a final temperature of 308K was observed. Compared to wire mesh inserts alone, the simultaneous use of the inserts and spray injection resulted in enhanced temperature abatement. Compared with spray injection method alone, temperature abatement improvement was observed when inserts of sparse density were used along with spray injection. Although wire mesh inserts distract the contact of water droplets with hot air, the simultaneous use of the two methods resulted in an increased effective surface area because the surface area added by the inserts is larger than the surface area lost by the droplets coming to contact with the inserts. When inserts with more compacted structures are used, the temperature abatement was less than the spray injection alone. This seems to suggest that the contact surface lost by the droplets is more significant than the extra surface area added by the inserts. Since the geometries of mesh inserts used in this study are different from each other, temperature increase patterns at certain pressure levels are compared. Clearly, spray injection improves compression efficiency to 95% from the base 80% efficiency of liquid piston compressor. This work uniquely highlights the further development of efficient air compression using spray injection and metal wire mesh.
Automatic Tuning of Vessel Models Offshore: A Feasibility Study Using High-Precision Data from Model Test
Authors: Kaasen Karl E. , Berget Kjetil , Lie Halvor , Bjørkli Rune
Published: April 2020

Model-based prediction of vessel response is valuable for planning and execution of marine operations. Response-based operation criteria are expected to give less downtime and cheaper and safer operations than criteria based on wave height and wave period. At least this holds if the response model has sufficient accuracy. The accuracy can in principle be improved by tuning the model using measured inputs and outputs. It is envisioned that an advisory system for planning and execution of marine operations will contain a module for continuous model improvement based on on-site measurements of excitation and response. A premise for this is that the measurements be of sufficiently high quality. To test the potential of automatic model tuning an established numerical vessel model is subjected to tuning with high-precision data from a model test with wave disturbance only. This may give information of how well modelling can be achieved using tuning under favourable conditions and serve as a benchmark for tuning under noisy conditions. In addition the results may give suggestions for improvement of the mathematical model. A prototype tuning software is written in Matlab. The tuning principle is to minimize the output error, i.e. the difference between measured and simulated response, by adjusting the model's parameters. For the minimization a quasi-Newton method is used. The tuning software is tested with data from the model test and found to function as intended. Examples of tuning are given.
Hybrid Directed Energy Deposition for Fabricating Metal Structures with Embedded Sensors for the Oil and Gas Industry
Authors: Juhasz Michael , Tiedemann Rico , Dumstorff Gerrit , Conner Brett , Lang Walter , MacDonald Eric
Published: April 2020

Hybrid additive manufacturing combines additive manufacturing (AM) and traditional subtractive processing with synergistic layer-by-layer access. The integration of both manufacturing processes leverages the benefits of AM - including complex geometries, mass customization and advanced high-temperature metal alloys - with traditional processes providing superior surface finish and dimensional accuracies. Hybrid AM integrates a suite of manufacturing processes within a single build volume and one benefit of this approach that was not previously leveraged is access to the structure at intermediate steps during fabrication. This access can enable the next generation of oil and gas industry offshore devices capable of providing sensing data from within the metal structural element. The sensors can inform the process of maintenance requirements and structural health management. In this report, an Ambit™ system was used to fabricate a tensile bar with a strain sensor encapsulated within the structure in order to provide a proof-of-concept demonstration for the oil and gas industries.
ABB Subsea Technology - Power for A New Energy Future
Authors: Vatland Svein , Thibaut Edouard , Lendenmann Heinz
Published: April 2020

The use of subsea processing equipment, which maintains, increases and speeds up oil and gas production, is now more and more widespread on offshore subsea oil and gas field developments. Further, there is a strong drive for electrification of offshore fields, both subsea and topside installations, to lower emissions. To meet the technical challenges of these developments, subsea transmission, distribution and conversion electrical equipment are developed through the ABB Subsea Power JIP where ABB, Equinor, Chevron and Total are partners. In 2013, ABB and its Joint Industrial Partners, Equinor, Total and Chevron, began an expansive project to design and test a complete subsea electrification solution for the oil and gas industry. To enable operations at remote locations in ultra-deep waters ABB developed modular equipment - components and assemblies - that integrate to form a subsea electrification system. The system consists of variable speed drives (VSDs), switchgear and a protection and control system for the transmission, distribution and conversion of power to subsea pumps and gas compressors at a peak capacity of 100 MW to water depths up to 3,000 meters; and with transmission distances up to 600km with lifetime requirements for up to 30 years. Topside area is freed, power supply demands and greenhouse gas emissions are reduced. Illustrates a typical subsea processing facility.
Kicks and Blowouts Prediction Before and During Drilling in the Over-Pressured Sediments
Authors: Shaker Selim S , Reynolds David J
Published: April 2020

Uncontrollable kicks are the most costly events that occur while drilling for oil and gas. Formation water flow sometimes turns to kicks that lead to life threatening and environmentaly disastrous blowouts. Prediction of the possible abrupt pressure surges that characterize the subsurface geological setting before drilling sheds light on some of the challenges that may be encountered along the bore-hole trajectory. This will also help curtail human error during penetration of certain zones along the well-hole trajectory, and consequently reach the objective depth safely and with less nonproductive time (NPT).

Before drilling, pore andfracture pressure predictions from seismic velocity are critical for assessing the economic feasibility and safety for the whole prospective trap. Integrating the seismic velocity drifts and the sequence stratigraphy semblance at the proposed location can point to the possible pressure transgressive intervals that can cause a sudden pressure surge (PS). Moreover, modifying the drilling tolerance window (DTW) to accommodate the expected hydrocarbon column in the prospective reservoirs reduces the potential of unexpected hard kicks at the shale – sand interface.

This paper briefly discusses the impact of subsurface geopressure compartmentalization on seismic velocity drift and consequently on PS. It also examines the subsurface geological setting that can cause substantial pressure increase penetrating the lithological interfaces. Therefore, the pressure transgression and expected excess pressure in pay zones should be encompassed within the numerical algorithm of the predictive model before drilling. Monitoring the logging while drilling (LWD) data slopes in shale beds can successfully point to a possible kick ahead of the drill bit. Maneuvering the mud weight and casing program while drilling within the DTW based on the modified numerical pressure profile can achieve safe drilling.

Examples from onshore and deep-water wells are shown. This paper covers several geological features that correlate to open bore-hole flows or kicks that sometimes develop to a blowout if the formation flow is not controlled by the right mud weight kill. Detecting these subsurface features and their associated seismic velocities before drilling can lead to safe drilling and avoiding NPT. Moreover, this paper sheds light on the potential to enhance drilling safety in advance, even in cases where managed pressure drilling (MPD) equipment is used.
Enhanced Rigid Jumper VIV Fatigue Assessment- Guidance Notes
Authors: Nair Aravind , Jaiswal Vivek , Fyrileiv Olav , Vedeld Knut , Zheng Haining , Huang Jerry , Tognarelli Michael , Goes Rafael , Bruschi Roberto , Bartolini Lorenzo , Vitali Luigio
Published: April 2020

To date, there are no publicly available, validated tools or industry accepted guidelines for the assessment of Vortex-Induced Vibration (VIV) fatigue of rigid Jumper (spool) systems. The existing state of practice has been to treat rigid jumper systems as free spanning pipelines and apply the associated design principles in DNV GL recommended practice DNV-RP-F105/DNVGL-RP-F105 (Free Spanning Pipelines). However, widely used rigid jumper systems such as the M-shape jumper systems are subjected to complex flow fields around their legs and bends and fall outside of the test data used to generate the free-span response model in DNV GL Recommended Practice (RP). A Joint Industry Project (JIP) ‘Jumper VIV JIP’ that included BP, ExxonMobil, Petrobras, Saipem and DNV GL was conducted between Dec. of 2014-2016 to collectively tackle the technical issues related to the VIV design of rigid jumper systems.

Through the JIP study, measured responses from ExxonMobil's jumper tow test data were used to develop new response curves for jumper systems in pure-current condition. Curves for in-line and cross-flow responses were initially developed by classifying the measured responses into in-line or cross-flow directions and compared against the existing DNVGL-RP-F105 response curves. Due to potential ambiguity in classification and application to Jumper Design, a more general curve that does not rely on directional classification has also been generated. Due to the differences in behavior of rigid jumper systems to that of free spanning pipelines, a new VIV guidance report was developed as part of the JIP deliverable. Principles and philosophies in the DNV-RP-F105 were followed in the development, but with the intent of identifying unique behavior of jumper systems for a subsequent update of the RP.

This paper presents the Guidance notes from the JIP and forms the first release of Jumper VIV fatigue assessment approach to the Industry. ExxonMobil's model test data, the only known test data available in the industry, was used in the development of unique response model and the new design guidance. The paper includes the new response model along with VIV screening, safety factors and unique considerations required for fatigue assessment of jumper systems.
Smart Monitoring and Failure Forecasting for In-Line Blowout Preventer Valves
Authors: Yoder Randy Thomas , Pereira Paul Christopher , Hoang Cam , Mutlu Mete , Lane Surrey , Panjwani Naveed
Published: April 2020

The oil and gas drilling industry is amid a digital transformation, especially regarding the digital oilfield, smart operations, and predictive maintenance. Traditional scheduled maintenance approaches to equipment replacement have been proven as inefficient[EP(1] [YR(2], as not just time in service, but operational and system variables have a significant impact on useful life. (Temer and Pehl, 2017). Reactive approaches to maintenance by responding to failure, has increased risks for downtime and safety, especially in consideration of critical drilling and safety components at the well center critical path. This paper describes an approach, through an in-line blowout preventer valve (IBOP) predictive failure use case, of smart equipment monitoring and reliability centered maintenance (RCM), supported by modern digitalization technologies, and the industrial internet of things (IOT).

To achieve this, extraction, transformation, and loading various data into a more unified analysis platform for usage along with loading aggregations and forecasting analysis was performed. Analyzing the SCADA data from the drilling rig, a logic-based algorithm was applied to identify IBOP usage cycles, from several separate signals. This created a dense data set of time series data identifying equipment loading cycles allowing analysis of a reliability centered maintenance health assessment and threshold. Historical usage was analyzed and forecasted using autoregressive integrated moving average to identify statistical approximation for the date where the forecasted usage would meet the health threshold, with results visualized into an interactive dashboard for operators.

The identification of a forecasted date where equipment usage is expected to cross the reliability centered maintenance threshold can be used for rig maintenance preparation and planning. Decision layer content, in the form of an interactive dashboard and scheduled reporting, can be employed to keep maintenance crews aware of usage progression toward the threshold.

Acquisition of data for analysis from many different systems and formats is challenging, especially for technical and engineering disciplines not fully aligned with traditional information technology (IT) skillsets, techniques, or platforms. Enabling flexibility for experimentation for new analysis can be by code-free, but code-friendly, data acquisition and analysis platforms that can be utilized at the onset of these advancements toward RCM. A data-fusion approach, methodically using multiple digitalization platforms, is employed as a strategy for improving condition monitoring, health assessment, and awareness. The application of new feature engineering and machine learning (ML) offers iterative improvements to RCM based health prognostic signals.
Subsea Processing Systems Predictive Maintenance Enabled by Condition Monitoring System
Authors: Arcangeletti Giorgio , Gambella Luca , Aloigi Elvira , Radicioni Alessandro , Novello Marco , Bacati Fabrice , Shaiek Sadia
Published: April 2020

Given the increasing level of technology readiness associated with subsea processing equipment under the trust of ambitious and challenging subsea field development schemes, in order to allow or enhance the hydrocarbon production and/or to reduce topside space requirements, oil and gas Operators are more keen to sanction new projects involving active subsea equipment.

The above scenario will most likely be the driver for a step-up towards a further communication link between subsea equipment (e.g. subsea pumps, compressors, separators, ancillary systems, etc.) and the end user. This link, enabled by a brand-new Condition Monitoring System, will be in addition to already consolidated subsea control system technologies and will pave the way for predictive maintenance operations of subsea processing systems.

Through the acquisition of subsea processing systems specific parameters detected during their operation and comparison with the relevant normal (baseline) conditions associated with each piece of equipment and/or typical component failure modes, it will be possible to monitor the deterioration of the equipment. It will also be possible to understand if it is time to plan a maintenance campaign for the system or if it can be postponed or moved up with respect to the MTBM of the system.

The condition monitoring system will collect a huge amount of data regarding system and components status, operating conditions and performances, and by tracking the collected information, it will be able to build a system history. This becomes the feed in a machine learning process that will regularly increase the level of confidence under real conditions of the subsea equipment laid far from the Operator's sight.

This paper will focus on a condition monitoring system concept applied to Saipem technologies for subsea processing.
China's Deepwater Field Development: Subsurface Challenges and Opportunities
Authors: Li Hangyu , Zhang Ming , Lau Hon , Fu Shiwen
Published: April 2020

At present, China has three major deepwater oil and gas fields located in the Qiongdongnan and Pearl River Mouth basins in the South China Sea (SCS) at water depths ranging from 300 m to over 1500 m. In this paper we compare the geology, reservoir and fluid properties and development concepts of these deepwater fields with those in the Gulf of Mexico (GOM), Nigeria and Brazil. Based on this comparison, we have identified several key subsurface challenges and opportunities for future deepwater field developments in the SCS. Major subsurface challenges include smaller in-place volumes, heavier oil, lower reservoir energy and higher reservoir temperature. Opportunities identified include locating continental margin systems with high accommodation volumes and thick sandstone supply, use of alternative development concepts such as Floating Liquified Natural Gas (FLNG) and complaint platforms with dry tree wells and learnings from the recent development of lower-permeability reservoirs in deepwater GOM and the heavy oil deepwater developments and CO2 handling techniques in Brazil.
Technical and Economical Screening of Chemical EOR Methods for the Offshore
Authors: Muriel Herman , Ma Shijia , Sofla Saeed Jafari Daghlian , James Lesley Anne
Published: April 2020

Enhanced oil recovery (EOR) and maximizing recovery from declining production fields remain a challenge in the offshore industry. The challenge is to find an EOR method that is both technically and economically feasible considering the high capital and operating costs in the offshore environment. The goal of this work was to conduct a simple cost-benefit analysis based on a technical, facility, and economical screening of chemical EOR methods applicable to the offshore. Offshore Newfoundland, Canada is used as a base case as it represents a challenging geographical environment. The reservoir properties are good, based on volumetrics and characteristics, but the fields are located over 300 km offshore in a harsh environment where operational costs are high.

A data mining approach was used for the EOR screening process. Data from over one thousand core flooding experiments investigating various chemical EOR methods, including surfactant, polymer, alkaline-surfactant (AS), alkaline-surfactant-polymer (ASP), nanoparticle, and low salinity water injection (LSWI), were collected. Factors with the greatest influence on the performance of a given EOR method were statistically examined and discretized. The ranges of recovery factor, rock type, chemical concentrations, and the most commonly used chemicals are presented in this review paper. Economic factors examined included capital expenditures (CAPEX) and the operating cost of production (OPEX). Benefits are found to be strongly related to oil production and Brent crude oil forecasts. Sensitivity studies of the recovery factor ranges with the different chemical concentrations, net present values (NPV), and the influence of the inflation were all taken into consideration. Two different injection plans were considered: injection from day one of production, and injection after secondary production. The highest CAPEX and OPEX were calculated for the ASP method, whereas LSWI resulted in the lowest. The results indicate that most of the chemical EOR methods could be economically successful, however, the timing of implementation will affect the potential benefits. If high recovery and low chemical concentrations are considered, ASP flooding is the most successful chemical EOR method when injecting from day one. However, if the EOR method starts after a decline in production, surfactant flooding proves more beneficial, regardless of the scenario considered. This paper presents a systematic approach to chemical EOR screening, combining available technical data using a data analytics approach with economic and technical uncertainty.
Autonomous Non-Destructive Remote Robotic Inspection of Offshore Assets
Authors: Ivan Vladimir , Garriga-Casanovas Arnau , Merkt Wolfgang , Cegla Frederic B. , Vijayakumar Sethu
Published: April 2020

Offshore assets suffer from material degradation over their lifetimes. Regular inspections are necessary to prevent failures and to reduce the cost of maintenance. These often require downtime of the asset and can involve risk to human workers who have to be sent to the offshore location. In this work, we present a non-destructive (NDE) system in conjunction with a robotic platform, which can perform inspections of the thickness of a component, for example from the outside of a tank or a pressure vessel. The NDE system consists of a digital acquisition system and an electromagnetic acoustic transducer (EMAT). The EMAT generates an acoustic wave, which reflects from the internal features of the component. The wave is received by the same device. The received signal is then processed by the acquisition system to determine the thickness of the component. The NDE system is integrated with a robotic platform that can autonomously or semi-autonomously perform scans of the asset. The robot platform presented in this work uses sensor fusion, machine vision and state of the art motion planning techniques to build a map of the material quality in 3D. This is achieved by exploiting the precise movement of the robot end-effector along the surface of the asset and then integrating the position of the NDE sensor. The collected data is then presented to the remote operator in a user-friendly way, which allows them to evaluate the state of the asset. We validate this system using material samples with known defects. We performed experiments in a controlled environment, and we demonstrate the system in a case study at a testing facility operated by our industrial partners.
Thermal Mitigation Design for Appomattox Flowlines
Authors: Ouyang Kevin X. , Dupre Mike , Schoppa Wade , Hsu Ta-Ming , Lee Liang-Hai
Published: April 2020

Novel methods were required to address the high operating temperatures of the Appomattox flowlines. Appomattox is predicted to operate as high as 365F, requiring thermal mitigation along the length of the flowline and anchoring at the base of the riser. Existing thermal mitigation methods were screened but were found unacceptable. Alternatively, a system of multiple buoyancy modules was found to be highly efficient and reliable to address the thermal expansion along the length of the flowline. Also, a unique rigid anchoring system was designed to restrain the riser base. Appomattox began production in Q2 of 2019. A flowline survey performed in Q3 2019 demonstrated good alignment with the analysis predictions for buckling locations, shapes and buckle magnitudes.
Dynamics of Hydrate Behavior in Shut-In and Restart Condition in Two and Three Phase System
Authors: Kakitani Celina , Marques Daniela C. , Neto Moisés A. Marcelino , Teixeira Adriana , Valim Leandro S. , Morales Rigoberto E. M. , Sum Amadeu K.
Published: April 2020

The oil and gas production in deeper water scenarios (e.g. pre-salt) has been increasing due to the growth in industrial production. The exploration fields under more severe conditions is accompanied by concerns about solid precipitation/deposition and hydrate formation. Transient operations, involving shut-in and restart is the most challenging scenario with risk for hydrate problem. The residence time of the production fluids associated to the rate of heat loss to the ambient seabed during the period of shut-in may increase the potential risk of hydrate blockage. This work is focused on understanding the hydrate formation, breakup, agglomeration and deposition, reproducing the shut-in and restart conditions in a lab-scale. Experiments were performed using a high pressure cell coupled to a rheometer using a custom-designed impeller and a rocking cell experiments with visual capabilities. A two-phase (water and gas) and three-phase (water, oil and gas) systems were used in the experiments. Also, the impact of the shear applied at restart on the hydrate morphology was evaluated. The viscoelastic behavior was observed in most shut-in and restart tests. Understanding the mechanism of hydrate formation and agglomeration during transient conditions may help to develop strategies to avoid hydrate plugging and allow the formation of a hydrate slurry yielding flowable conditions.