bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancing Drill Bit Connections for Reliability and Longevity
Authors: Allison Cliff , Borders Zachary , Donaldson Justin , Grimes Robert E. , Lee Roger K. , Slavens Stephen , Daechsel Dustin 
Published: March 2022

Abstract
Pursuit of drilling the technical limit has been a primary driver of cost and cycle time reduction from the onset in North America shale. This is increasingly evident in today's downhole mud motors, where motors designed to drill in 6.75 in. hole are now rated for 500+hp and over 10,000 ft-lbs of torque. Every unit of power added stresses current materials to the limit and increases the risk of mechanical failure. As will be demonstrated in the following sections, the increased power delivered to the bit now exceeds the strength and reliability of the standard 3 ½ REG connection for drill bits. The integrity and longevity of the drill bit pin connections is the primary focus of this paper.
Details are provided of the technical aspects of drill bit solutions that meet current drilling requirements and recognizes industry trends that will continue to present future challenges for bit connections. This paper also describes the collaborative partnership between an operator and bit service provider that led to success and the development of a long term plan for continuing success.
An Assessment of the Kick Tolerance Calculation, its Uncertainty and Sensitivity
Authors: Thorogood John , Robertson Ewen , Castillo David , Sawaryn Steve 
Published: March 2022

Abstract
Much of the contemporary literature on kick tolerance relates to the practical aspects of the calculation and the effects of the underlying assumptions and necessary simplifications. It tends to a formulaic approach involving unconstrained uncertainties about pore pressure, kick intensity, drilling fluid density safety factors which tend to overlook the inherent complexities of the subsurface environment and the reality of model limitations.
The literature on kick tolerance highlighting the strengths, weaknesses and limitations of the classic calculation is reviewed before describing a first-principles approach to determining the consequences which casing seat strength limitations and strength variations in the overall open-hole section imposes on safe well designs as a result of uncertainties in the input variables and basic model assumptions.
The classic kick tolerance calculation, together with its associated assumptions, yields only a single value for a given set of inputs. The uncertainties and sensitivities are those introduced by the variables and the choice of operational procedures. The Monte Carlo method is employed to explore the effect of uncertainties in the input parameters and associated assumptions.
The analysis is based on the Driller’s Method for kick circulation, with a single bubble insoluble gas with optional allowances for gas gravity and thermal regimes. To examine the various factors influencing kick tolerance, the problem is framed graphically in terms of an allowable influx volume, the dependent variable, against bottom hole pressure, the independent variable, on which pore pressure, its uncertainty, possible variations in shoe strength, strength in the open-hole section, drilling fluid density with associated equivalent circulating density and swab effects can be examined.
Application of the new approach demands significant prior work to determine the uncertainties inherent in the problem. Some of these uncertainties, such as drilling fluid density variations, swabbing and equivalent circulating density must be evaluated by the engineer as part of the normal well design. Other factors, such as shoe strength, pore pressure variability and formation depth error bars must be developed as part of a multi-disciplinary effort within the planning team. Often ignored due to the spatial uncertainties, natural fractures intersecting the borehole could be inherently unstable and prone to hydraulic communication between borehole and formation.
Synthesising some of these considerations into a simple calculation framework allows the effect of these parameters either individually or collectively to be quantified and provides a view of the potential geological uncertainties inherent in a well design. The approach offers a starting point for thinking about the nature of geological uncertainties and carrying them into drilling programmes
Mud Motor PDM Dynamics: A Control Model for Automation
Authors: Samuel Robello , Baldenko Fedor , Baldenko Dmitry 
Published: March 2022

Abstract
Automating drilling operations using modern technology with intelligent control systems is prioritized with respect to drilling process development. The process becomes more complex when a mud motor is used because of the dynamic properties of the control objects, which are interconnected from the surface feed mechanism to the bit. Development of a model that better predicts the dynamic condition when a mud motor is used is discussed. The dynamic characteristics of a positive displacement motor (PDM) are considered as a single system by coupling the hydromechanical processes. This includes, transient pressure, drillstring dynamics, kinematics of the PDM rotor, the mud pump and dampener, dynamic characteristics of the bit, and internal and external system disturbances. The mathematical model includes the hydraulic and mechanical subsystems as well as the relationships of these subsystems. The subsystems include the equations of the processes in their constituent links (i.e., drillstring, hydraulic line, mud pump, downhole motor, bit, and bit feed mechanism). The nonlinear system of differential equations are solved using numerical methods with appropriate boundary conditions in a two-way loop for regulating the load on the bit and flowrate.
The study shows that the transient behavior of the mud motor must be accounted for when automating the drilling process. It has been observed that an instantaneous change in the load results in the transition of the hydraulic motor to a new steady-state mode gradually (for tens of seconds) and is influenced by the transient pressures in the string. The transient process (torsional vibrations) in the PDM occurs until the flow rate stabilizes at the top of motor. A similar hydromechanical effect, if the PDM does not have a sufficient torque reserve, can lead to deceleration of the PDM and might require correction of the weight on bit (WOB) and flow rate. The study also showed that the effect of pulsation dampener resulting in an uneven flow leads to uneven rotation of the mud motor shaft, even if a constant load on the bit is maintained. This study revealed that evaluation of the influence of the deviation of one of the operating parameters on the behavior of the dynamic system is important (Tokhonov, 2019). The choice of optimal control algorithms depends on the accuracy of determining the transfer functions, in particular, with respect to the change in the WOB. Further transfer functions derived can be used to control the surface parameters for drilling.
Real-Time-as-a-Service Increases Efficiency, Agility and Consistency
Authors: Sadlier Andreas , Baksh Nazaad 
Published: March 2022

Abstract
Oil and gas operators use data collected from well operations for real-time monitoring, performance analysis and remote operations. Service providers typically operate real-time data systems from local data centers. They manually provision capex-heavy IT infrastructure and applications for each operator and rig. This may lead to overcapacity and inconsistent performance operating at scale.
We commissioned a public-cloud, real-time-as-a-service solution which increased performance and consistency of real-time data access for a Norwegian operator. It also improved the service provider's operating efficiency and ability to accelerate the pace of innovation.
A distributed architecture reduces failure points and enables horizontal scaling. Cloud provides elastic scaling to provision the right amount of compute resources to meet demand. Open-source technologies lower maintenance cost and reduce the technical debt accumulated maintaining the proprietary incumbent system.
Close collaboration between the operator and service company enabled successful commissioning on six rigs. Real-time data feeds were previously collected by six independent IT systems hosted in a regional data center. The live data streams were successfully transitioned during active drilling activities, without interruption to remote operations.
Real-time performance increased by more than 83%. The operator also observed a significant improvement in service and data quality. During the transition period, minor updates were deployed with zero downtime and no impact to the operator. Shortly after rollout, the support team remediated a performance bottleneck in just minutes. Prior solutions would typically require procurement and configuration of network hardware, taking months.
In contrast to proprietary software solutions, an open architecture facilitates easy integration of existing software investments. Application programming interfaces simplify the development and connectivity of new real-time applications. Finally, cloud-native solutions accelerate the pace of innovation. Access to cloud services like analytics platforms enable continual integration of digital capabilities with real-time data.
An Ensemble-Based Solution for Automating Drilling Engineering: Application to Directional Surveying
Authors: Cayeux Eric , Dvergsnes Erik , Carlsen Liv , Mihai Rodica 
Published: March 2022

Abstract
Drilling engineering and drilling operation are two steps of the well construction process that are treated sequentially and separately. The interface between those two steps is the drilling program, i.e., a unique solution that has been singled out and analyzed in detail during well planning. However, when an unexpected situation occurs during the drilling operation, the drilling program is of little use to take informed decisions as it does not contain any information about acceptable tolerances.
An alternate approach for passing information between the planning stage and the operational phase is to capture the constraints and margins that should be respected during the well construction. These constraints can be combined with the foreseen uncertainties that are embedded at every stage of the design and engineering process. Such uncertainties are associated with expected available measurements during the drilling operation, but also uncertainties that exist on the modelling side as well as the natural deviations that will take place during the drilling operation. From this point of view, the drilling program turns to be an ensemble of possible solutions, each of them being associated with potential risk levels.
To illustrate how such a method can be applied in practice, the paper explains how the surveying program can be automatically generated to respect anticollision criteria with neighboring wells and acceptable driller's target dimensions. To achieve this, it is necessary to have a very generic well path calculator. Then a well path generator can instantiate hundreds of well path realizations respecting geometrical constraints related to the subsurface environment, e.g., angle of incidence to cross faults, angle of penetration of hard stringers, but also other constraints such as those related to geo-mechanical margins. Wellbore position uncertainties can be evaluated based on a surveying program, and well paths can be nudged to respect anti-collision criteria with neighboring wells. The dimension of the driller's target can also be estimated as a function of the wellbore position uncertainty and its geological boundaries. By investigating multiple combinations of survey instruments for the surveying program, it is then possible to obtain the set of surveying programs that provide sufficient margins for anti-collision and acceptable dimensions for the driller’s target.
The result of the analysis is automatically generated surveying programs and their envelopes of well paths that respect a set of subsurface and directional surveying constraints. One of those possibilities can be chosen as well as an associated well path that gives a large clearance to the constraints. At the operational stage, when unexpected situation occurs, acceptable margins are readily available allowing for deviating from plan in an informed way and without recourse to qualitative judgement.
Real-Time Reamer Vibration Predicting, Monitoring, and Decision-Making using Hybrid Modeling and a Process Digital Twin
Authors: Shi Jibin , Dourthe Laetitia , Li Denis , Deng Li , Louback Leonardo , Song Fei , Abolins Nick , Verano Fernando , Zhang Pusheng , Groover Joshua , Gomez Falla Diego , Li Ke 
Published: March 2022

Abstract
In hole enlargement while drilling (HEWD) operations, reamers are extensively used to enlarge the pilot hole. Reamer wipeout failure can cause additional bottom hole assembly (BHA) trips, which can cost operators millions of dollars. Excessive reamer shock and vibration is a leading cause of reamer wipeout; therefore, careful monitoring of reamer vibration is important in mitigating such a risk.
Currently, downhole vibration sensors and drilling dynamics simulations are used to comprehend and reduce downhole vibration, but vibration sensors cannot be placed exactly at the reamer to monitor the vibrations in real time. Drilling dynamics simulations are difficult to calibrate and are computationally expensive for use in real time; therefore, the real-time reamer vibration status is typically unknown during drilling operations.
A process digital twin using a hybrid modeling approach is proposed and tested to address the vibration issue. Large amounts of field data are used in advanced drilling dynamics simulations to calibrate the HEWD runs. For each HEWD section, calibrated drilling dynamics simulations are performed to comprehend the downhole vibration at the reamer and downhole vibration sensors. A surrogate regression model between reamer vibration and sensor vibration is built using machine learning. This surrogate model is implemented in a drilling monitoring software platform as a process digital twin. During drilling, the surrogate model uses downhole measurement while drilling (MWD) data as input to predict reamer vibration. Wipeout risk levels are calculated and sent to the operators for real-time decision making to reduce the possibility of reamer wipeout.
Large volumes of reamer field data, including field recorded vibration and reamer dull conditions were used to validate the digital twin workflow. Then, the process digital twin was implemented and tested in two reamer runs in the Gulf of Mexico. A downhole high-frequency sensor was placed at the reamer in one field run and the recorded sensor vibration data and corresponding reamer dull conditions showed a very good match with the real-time digital twin predictions. The field tests demonstrated the feasibility and accuracy of the digital twin and established a method for aiding in future real-time decision making.
State-of-the-art downhole sensors, drilling dynamics simulation packages, large amounts of field data, and a hybrid approach are the solutions to building, calibrating, and field testing the reamer digital twin to ensure its effectiveness and accuracy. Such a hybrid modeling approach can not only be applied to reamers, but also to other critical BHA components.
Drilling Practices and Workflows for Geothermal Operations
Authors: Dupriest Fred , Noynaert Sam 
Published: March 2022

Abstract
Over a three-well program the FORGE drill teams reduced well times by more than half, with instantaneous ROP increased over 400% in the thick granite pay zone. At the same time, record footage per bit was increased over 200%. The physics-based, limiter-redesign workflow utilized is described, along with specific changes in design and operational practices. Both are expected to yield similar results in any hard rock, geothermal or similar operations.
In 2020, the U.S. Department of Energy (DOE) funded a group at Texas A&M University to develop physics-based practices for the geothermal industry, similar to those that have enabled large gains for many operators in the petroleum industry. Wells in the Frontier Observatory for Research in Geothermal Energy (FORGE) were used to develop and test the workflow and practices. The effort began with sixteen hours of training for all team members, including drilling management. Changes were made in the daily workflow, such as periodic parameter testing, real time recognition and response to the common drilling dysfunctions, limiter identification, and daily discussion of the physics of each limiter and the immediate response required that included remote support personnel. The continual daily emphasis on identification of limiters, combined with training in how each limiter physically worked, created an enabling environment for change
Some of the key performance limiters addressed in these FORGE wells included previously held beliefs about limitations on WOB with PDCs, modifications to reduce BHA whirl, use of high WOB to suppress bit whirl, identification and avoidance of resonant RPM, BHA design and drilling practices to reduce the amplitude of borehole patterns to improve weight transfer, and the use of high spurt loss fluid (water) to achieve brittle rock failure. It was eventually possible to increase WOB to the structural limit of the bits (i.e., 68k lbs on 10-5/8" PDC). The bit vendor was engaged continually in daily analysis of digital data and dulls, and bits were redesigned to redistribute cutter wear, increase aggressiveness, and improve life through the increased use of shaped cutters. A significant finding was that contemporary PDC cutters remained relatively unworn for long distances in the FORGE granite regardless of WOB used, if the team is trained to manage dysfunction The mechanism through which the cutters eventually fail is discussed, along with operational and design practices to further extend the run lengths.
This paper is intended to serve as a reference, with the basic concepts, science, and real-time practices an operator may consider in developing its physics-based, limiter-redesign workflows.
Successful Planning and Implementation of First South Texas U-Turn Lateral
Authors: Schultz Riley , Kiefner Joe 
Published: March 2022

Abstract
Today’s legacy fields require innovative solutions for developing capitally efficient projects within highly developed acreage blocks. As another tool to improve well economics, a U-turn lateral strategy was implemented in the Eagle Ford Shale in 2020. This wellbore trajectory resulted in capturing a 9,200 ft equivalent lateral length well in a 5,000 ft-wide lease space. This successful U-Turn trajectory test in South Texas has created new economic project opportunities for the company and has increased optionality within challenged lease spaces across the field.
An Integrated Methodology for Green Human Resource Management in Construction Industry
Authors: Darvazeh Saeid Sadeghi , Mooseloo Farzaneh Mansoori , Aeini Samira , Vandchali Hadi Rezaei , Tirkolaee Erfan Babaee 
Published: March 2022

Abstract
Today, by increasing public awareness about environmental issues and pressures from governments and other stakeholders companies have dealt with environmental challenges more than ever. This paper focuses on environmentally sustainable performance using an integrated method based on meta-synthesis, Delphi, and structural equation modeling (SEM) methods are utilized in different phases of the methodology. In the first phase, an in-depth review of green human resources management (GHRM) literature is conducted based on the meta-synthesis method and as a result, 38 codes were extracted. Then, to adapt and customize the codes with the nature of the construction industry, 2 rounds of the Delphi method are applied to collect the expert judgment from a panel of 15 industry professionals, resulting in 21 codes in 7 categories. Finally, to verify the proposed model the data from 33 Iranian construction companies were collected and by using SEM, 15 factors in 5 categories are presented. The findings indicated that among 9 main GHRM components extracted from the literature, just 5 components including green recruitment and selection, green performance management, green- reward, green-based employee empowerment, and green training have significant and positive relationships with GHRM. The paper also provides some managerial insights and some future directions.
Scaling debt for nature swaps – which nature, how much debt and who pays?
Authors: Nedopil Christoph , Yue Mengdi , Hughes Alice 
Published: March 2022

Abstract
With the upcoming launch of the post-2020 global biodiversity framework and an accelerating sovereign debt crisis in many emerging economies related to COVID19, we analyze how the resurgent call for debt-for-nature swaps could conserve currently unprotected biodiversity priority-areas for six biomes and support debt restructuring in 67 countries under the World Bank’s debt service suspension initiative. Using novel methods and data, we find that the 67 countries hold over 22% of global priority-areas, 82.96% of which is unprotected. However, even when using conservative cost estimates, protecting 100% of those currently unprotected areas would only convert 0.1% of public debt for 35 of the 67 countries and would not significantly reduce debt levels. Applying DNS in the remaining countries would allow the protection of 11-13% of the Earth’s currently unprotected priority areas and would require particularly China to engage in swapping between USD2.8 and 5.5 billion in debt.
Evaluation of the Effect of Oxygen-Helium Mixture on the Severity of Cough in Patients with Coronavirus Infection
Authors: Tsygankov K. A. , Lakhin R. E. , Shchegolev A. V. , Zhdanov A. D. , Klimov A. G. 
Published: February 2022

The objective: to evaluate the effect of inhalation of heated oxygen-helium mixture on the severity of cough in patients with coronavirus infection (COVID-19).Subjects and Methods. A single-center randomized prospective study was conducted. Group 1 (control) (n = 32) included patients who received standard COVID-19 therapy. Group 2 (n = 29) included patients who had inhalations with heated oxygen-helium mixture (OHM) in addition to standard treatment. The severity of cough was assessed using 6-point scale (0 ‒ no cough; 1 ‒ single cough impulse; 2 ‒ rare cough during the day; 3 ‒ frequent cough that does not affect daytime activity, 4 ‒ frequent cough that reduces daytime activity due to cough; 5 ‒ severe cough in which daytime activity is impossible), and respiratory rate (RR) was also for 7 days from the moment of inclusion in the study.Results. Cough symptoms of varying severity were detected in all patients included in the study. A prolonged coughing fit led to decrease in blood oxygen saturation. In the control group, intensive cough persisted for the first 4 days and subsequently decreased with the favorable course of the disease. In the group, where OHM was used, on the 3rd day, the severity of cough decreased to 2 scores compared to the initial 4 scores (p = 0,005). The use of OHM allowed reducing the severity of cough versus traditional therapy. The analysis of intergroup comparisons showed differences starting from day 3 (p = 0.014): in patients of Group 2 (with the use of OHM), cough was mostly rare during the day, at the same time, frequent cough persisted in patients of the control group according to assessment of the severity of daytime cough. When analyzing RR, it was revealed that in Group 2, RR from day 2 was below the one in the control group, in which no changes were detected during the entire observation period.Conclusion. The use of inhalation of oxygen-helium mixture allows reducing the intensity of cough and respiratory rate in patients with COVID-19.