bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-Frequency Torsional Dynamics of Drilling Systems: An Analysis of the Bit-System Interaction
Authors: Jain Jayesh R. , Oueslati Hatem , Hohl Andreas , Reckmann Hanno , Ledgerwood L. W. , Tergeist Mathias , Ostermeyer G. P. 
Published: June 2014

Abstract
Recent advances in downhole vibration monitoring have enabled detection of high-frequency torsional oscillations (HFTO) of drilling systems in the field. The general understanding of torsional behavior of drilling systems derived from elaborate efforts in the literature does not explain the mechanism responsible for HFTO. Even for the well-known and extensively studied stick/slip vibrations, the mechanism perpetuating the vibrations is not agreed upon by researchers.
The paper discusses findings from experimental and analytical studies regarding the HFTO of bottomhole assemblies (BHAs). The phenomenon is investigated and reproduced in field tests, full-scale laboratory tests, and computer modeling. Drilling conditions are identified in which the drilling system is prone to exhibit the vibrations. Interaction of the bit and the drilling system, which can generate self-excited vibrations, is investigated using analytical methods. Cutter-rock interaction as a possible excitation source is studied using laboratory experiments to elucidate its interaction with the system.
The integrated analysis investigating rock, cutter, bit, and BHA interaction identifies HFTO as a bit-induced BHA torsional resonance that can occur at vibration modes higher than the fundamental mode of the BHA. It is demonstrated that modes most susceptible to exhibiting HFTO can be identified and the dominant mode predicted. The understanding gained can be employed to mitigate torsional resonance and enhance drilling performance.
Improving Safety Through Logic: Programmable Logic Controller for Conventional Casing Running Equipment
Authors: Naill N. , Madgwick S. , Bratten C. , George M. 
Published: June 2014

Abstract
Running casing with conventional equipment is a labor intensive process requiring multiple personnel on the rig floor. Due to the dynamic environment of running casing with this equipment, there is elevated potential for accidents. Two specific operational hazards associated with hydraulic power tong operations (the "mule kick" and "rattlesnake") have been addressed, and the authors are developing solutions to mitigate future related incidents. A new system, utilizing a programmable logic controller (PLC) and position sensors, as well as hydromechanical and electromechanical devices, has been devised to reduce the chance for injury and enhance safety for casing power tong operators. Risk mitigation through engineered safety controls is a primary objective for service companies, and the operators and contractors they work with.
Hydromechanical, electromechanical, and electronic control (PLC) devices for land-based, conventional casing equipment are under development and revision. These devices are being customized for incorporation into power tongs and hydraulic power units. In conventional operation of power tongs, the power unit modulates the amount of hydraulic power provided to the tong based on required flow rate and pressure. The PLC provides the ability for electronic communication between the power tong and power unit, virtually eliminating lag in response time. The logic control can also determine, based on the magnitude of tension in the backup line, if the tongs are actively in make-up or break-out mode. These devices under development will prevent the violent backlash and stored energy associated with the "mule kick" and "rattlesnake". In addition, due to the flexibility of the system, Human Machine Interface (HMI) screens can be provided to adapt the system to changing conditions.
The application of the logic controller and mechanical devices on land-based, conventional casing running equipment is a significant step in reducing operator and equipment error, and increasing the casing crew's safety threshold. This paper will discuss the evolution of this system, from conception to application.
A Method to Evaluate Lost Circulation Materials—Investigation of Effective Wellbore Strengthening Applications
Authors: Savari Sharath , Whitfill Donald L. , Jamison Dale E. , Kumar Arunesh 
Published: June 2014

Abstract
With increased drilling activity in deeper, harsher, and more complex environments, controlling non-productive time (NPT) during drilling is critical to lowering the cost of well construction. Lost circulation (LC), one of the main contributors to NPT, is a widely discussed topic drawing industry attention, as is evident from recent publications and forums/workshops on the topic. The literature on LC reveals several means of mitigation, ranging from the simple use of Lost Circulation Materials (LCMs) to the use of gunk/chemical sealants and methods for altering near-wellbore stresses (stress caging or wellbore strengthening). There is a subtle difference between lost circulation and wellbore strengthening, and any research should help facilitate a better understanding of the two.
Presented previously (Kumar et al. 2010; Savari et al. 2012) were novel insights into LCMs for wellbore strengthening applications. Continuing the research effort, this paper discusses another approach for designing LCMs to withstand higher wellbore pressures within a fracture. A property of Plug Breaking Pressure (PBP) was determined for different LCM combinations using a permeability plugging apparatus (PPA) with tapered slots. LCM combinations with differing mechanical properties behaved differently when compared using the PBP data. Particles, such as ground marble (GM), alone were not able to plug the tapered slot and hence the PBP was zero. Based on the previous work described by Savari et al. (2012), the addition of resilient graphitic carbon helped with plugging the tapered slot, with a PBP of approximately 900 psi. Adding fibers to the LCM combination was also evaluated. Plugging did not improve when fibers were added just to one other type of particulate LCM. But, the combination of ground marble, resilient graphitic carbon, and specific fibers was found to provide the most efficient plugging with the highest PBP of approximately 2,100 psi.
This work confirms that all LCMs are not equal and that the LCM type plays a role in terms of both plugging and "toughness" that better withstands displacement pressures. It also validates that, most of the time, combinations of LCM work more effectively compared to using just one type alone. The novel PBP data on different LCM combinations can provide a qualitative comparison of their ability to withstand displacement and/or failure pressures when designing LCM combinations in wellbore strengthening applications.
How can the Petroleum Industry Benefit from Human Reliability Analysis?
Authors: Li Yuandan , Cho Joseph J. , Ren Yali 
Published: June 2014

Abstract
In the petroleum industry, the study and impact of human reliability on safe and efficient operations is receiving heightened awareness. According to recent studies, human errors contributed to an estimated 60 to 90 percent of all accidents across many industries (petroleum, nuclear and aviation industries, etc.).
Human errors can result in two possible outcomes of concern: safety risks and the cost of failure. In operations where the consequences of accidents may be unbearable, the emphasis on safety drives the study and research of human reliability. This effort has led to a number of human reliability analysis (HRA) methods, and they provide useful references for managing human errors.
This paper examines how the petroleum industry could utilize and benefit from the available HRA methods by applying them to daily operations. Several HRA methods are reviewed in this paper from three aspects: human error identification, human error prediction of given tasks, and factors that contribute to human errors. A good data collection system can substantially support the HRA study qualitatively and quantitatively. This paper also introduces a practice for human error data collection that was implemented in the nuclear industry—human event repository analysis (HERA). Suggestions and remarks are provided about developing similar human error data collection systems tailored for the petroleum industry. The expected benefits of HRA include a better understanding of the causes and influencing factors of human errors in specific operation conditions, and insights into error-reduction measures for reducing accident risk and the cost of product failure.
Drill Cuttings Re-Injection Well Design and Completion: Best Practices and Lessons Learned
Authors: Gumarov S. M. , Shokanov T. A. , Simmons S. , Anokhin V. V. , Benelkadi S. , Ji L. 
Published: June 2014

Abstract
As part of the well drilling and completion process a significant amount of waste streams including drill cuttings, discarded mud, completion brine, oily drains, and residual pits volume are generated. These waste streams must be properly handled, treated and disposed of in a most environmentally friendly and compliant manner.
Drill cuttings sub-surface injection, or Cuttings Re-injection technology is one of the major widely used drilling waste management techniques in most global E&P areas and represents a process of degrading drill cuttings, mixing into slurry and injecting into the subsurface via pumping at pressure exceeding the formation's fracturing pressure gradient. As any subsurface operation the Cuttings Re-injection has its own inherited risks and complexities which must be proactively addressed via comprehensive front-end design to minimize those risks and potential eventualities. These risks and complexities are predominantly applicable to injection wells – a core asset in the injection system and key to the success of the entire drilling campaign.
Industry literature cites general guidelines for a safe cuttings injection well design and completion practices; however, this paper addresses and discusses different options, compares pros and cons and shares some best practices and lessons learned from large-scale injection projects. Topic included are: optimum tubing and casing design, solids settling and wellbore displacement efficiency in deviated wells, tubing erosion assessment and field observations, cement bond resistance to pressure-temperature cycles supported by surveillance results and perforation. This paper was developed based on challenging experiences in a broad practice as a cuttings re-injection international service provider and intends to complement previously published general guidelines with practical examples.
Advancing Deepwater Kick Detection
Authors: Johnson Austin , Leuchtenberg Christian , Petrie Scott , Cunningham David 
Published: June 2014

Abstract
Numerous developments in automation have made the modern mobile offshore drilling unit a marvel of engineering achievement and a model of efficiency. Yet, even with the surge in advancements, kick detection, which can be comparatively elementary for a fixed drilling unit, has proven significantly more difficult to master on a vessel which subject to wave motion and currents. A lack of consensus on universal standards and regulations have left kick detection largely ignored. But further, the lack of innovation has been coupled with drilling in greater water depths which are subject to the use of longer risers with greater volume and weight. Thus, in addition to the complications of dynamic environments are the material requirements to properly intervene during an influx event. Operators and shipyards have kept pace with these material issues by designing larger, smarter vessels with greater capacities and better controls systems to cope with the complexities of drilling in deepwater environments. Despite the best efforts and ballooning costs, influx events continue to occur because an operating envelope and a universal philosophy for deepwater kick detection have yet to be established.
With the primary driver for deepwater and ultra-deepwater drilling being to access the most productive formations possible, a recipe is formed such that a slight variation between formation pressure and fluid pressure has the potential to draw a significant hydrocarbon volume into the well bore. When well control procedures are initiated, a series of checks take place which, though proven and reliable for detecting kicks, consume valuable response time and potentially aggravate the initial problem. After an influx has been confirmed, remedial work often takes days and sometimes weeks to recondition the well for drilling. Whether in terms of personnel, equipment, facility, environment, or finance, the risk presented to the drilling operation by influx and loss events is substantial. Therefore, an advanced approach should be adopted which views kick/loss detection as a safety critical measurement and incorporates a modern, control system based design philosophy with established methods to overcome shortcomings.
This paper will describe experiences, challenges, and approaches to solving the problems related to creating an advanced early kick detection system suitable for floating mobile offshore drilling units. Necessary components, operational considerations, and design limitations will be discussed. Additionally, a discussion will offered on the current state of regulatory requirements related to kick detection and considerations for future standards.
The Need for High-Frequency Vibration Measurement Along with Dynamics Modeling to Understand the Genesis of PDC Bit Damage
Authors: Oueslati Hatem , Hohl Andreas , Makkar Navish , Schwefe Thorsten , Herbig Christian 
Published: June 2014

Abstract
Drilling vibration can be harmful to the bit and the bottomhole assembly (BHA), resulting in damage and tool failure and subsequent non-productive time (NPT). Bit damage while drilling offshore is costly, and any improvement in bit life can save multiple unplanned trips and lead to savings for operators. Consequently, dynamic dysfunctions have been the focus of industry research to understand and mitigate their effects.
In this paper, the authors present a field case study from an offshore application. A high-frequency, in-bit sensing device (1400-Hz sampling frequency) was installed into the bit shank in conjunction with a well-established measurement while drilling (MWD) tool in the BHA. The intent was to capture the dynamics behavior of the BHA and the dynamics directly at the bit. Multiple measurements along the BHA gave a better understanding of the behavior of the entire drilling system. The measurements were then used, along with dynamics modeling and simulation, to correlate bit and cutter damages with instances of backward whirl and stick/slip. The developed kinematic model of whirl corroborated well with measurements and showed how polycrystalline diamond compact (PDC) cutters can exhibit relative backward motion that potentially leads to severe cutter damage. The extended frequency range of the measurement module also enabled the capture of new dynamics phenomena at much higher frequencies than are usually reported in literature.
The insights gained in bit dynamics and cutter damage helped to improve bit design by building dynamically stable PDC bits with increased rate of penetration (ROP) and reduced NPT. The need for high-frequency measurements is also discussed and the benefits are presented, i.e., avoiding bit design iterations around misunderstood vibration issues. In today's challenging drilling applications, the measurements are important in characterizing the harsh drilling environment and understanding high-frequency dynamics phenomena that are rarely measured or discussed.
A Step Change in Deepwater Test Operations with Downhole Wireless Telemetry
Authors: Maizeret Pierre-David , Keidel Conrado , Nwagbogu Ifeanyi , Vannuffelen Stéphane 
Published: June 2014

Abstract
Drillstem tests provide crucial information about well deliverability and reservoir characteristics, but gathering such critical data may require many days of rig time, which can be prohibitively expensive in deepwater environments. As the information gathered during the test is generally available only when the string is pulled out of hole, well test engineers are usually conservative when designing the duration of the flow and shut-in periods to ensure sufficient data is acquired to meet test objectives. However, in some cases, the planned test durations were not sufficiently long to capture the necessary reservoir data for interpretation.
A relatively common practice of obtaining bottomhole data before the end of the test is running a conventional surface readout (SRO) system on electrical cable to establish communication with the bottomhole gauges, but this technique may pose a major risk to the operations. Recently developed wireless downhole reservoir testing systems can be the solution to this challenge. The system transmits information to and from the bottomhole tools in real time with no risk to the drilling operations.
This paper describes a field case where such a system was used on a deepwater well offshore Brazil. The wireless telemetry system took less time to rig up than wireline equipment and allowed the test sequence to be adjusted during the test. The data was available during flow and shut-in periods. It was used to monitor cleanup efficiency in real time as well as to obtain key reservoir information before ending the test. The reservoir engineers were able to
■ observe perforating guns' effect on pressure and confirm dynamic underbalance ■ compute productivity when the well was flowing ■ validate that sufficient data was acquired during the initial and main buildup periods ■ eliminate the need for a wireline run ■ establish reservoir pressure after the initial postperforating flow period.
The paper reviews the benefits and limitations of the current technology and makes recommendations on how to use the technology most effectively.
Modeling Method to Estimate the Casing Wear Caused by Vibrational Impacts of the Drillstring
Authors: Samuel Robello , Kumar Aniket 
Published: June 2014

Abstract
The increasing complexities of wellbore geometry imply an increasing potential of damage resulting from casing wear downhole. Much work has been performed to quantify and estimate wear in casing; however, the results of such predictions have been mixed. While the locations of critical wear areas along the casing string have been predicted fairly accurately, quantifying the actual amount of wear itself has been a challenge. The existing casing wear models were developed only for static wear conditions, where there is constant rotational contact between the tool joints and the inner wall of the casing. However, drilling activities and operating conditions have advanced rapidly, leading to several other downhole wear mechanisms contributing to casing wear.
The casing wear predicted using these static models cannot correctly estimate the actual volume of the wear, thus resulting in several different studies being conducted to improve the accuracy. This study is aimed at exploring and modeling one of the contributing factors to casing wear—wear caused by vibrational impacts of the drillstring on the inner wall of the casing. Impact wear in casing strings is observed at certain rotational speeds when the drillstring experiences resonating frequencies that lead to dynamic vibrations. These high-frequency vibrations generate an impact force acting on the inner casing wall as a result of the drillstring contact and thus influence the casing wear.
An analytical model to estimate and quantify the wear caused by drillstring impact is presented as a more comprehensive casing wear model. Various impact force models were considered in this study to better understand this phenomenon; namely, the parabolic model, the elliptical model, the cosine model, and the positively skewed force distribution model.
The different impact force distribution models were then applied to estimate downhole casing wear caused by impacts, and the estimates were compared to the linear static wear. As previously mentioned, static wear occurs because of continuous contact of the casing and the drillstring along a certain portion of the wellbore. Impact wear occurs over and above static wear, and the combined effect of both provides an improved prediction of the actual wear in casings downhole. This paper presents a field example to estimate the casing wear caused by impacts using a simulated case study. Estimation of the depth of the wear groove using the new casing wear model was alsoperformed using field drilling parameters and is presented as well.
Real-Time Operations Support for Geographically Dispersed Operations
Authors: Kucs Richard , Lehnert Wolfgang , Thorogood John , Spoerker Hermann , Whatson Neal 
Published: June 2014

Abstract
Presentations on real-time drilling support activities have been focused on large-scale operators or service companies that have full-time dedicated centers serving multiple rigs. These are staffed on a full-time basis with specialist monitoring teams and are supported by an extensive integrated communications infrastructure.
This paper addresses the problem faced by an operator working on a much smaller scale needing to provide a few geographically dispersed rigs with the benefits of real-time support technologies through high quality communications and a clearly defined workflow involving collaborative working between the rig, operations office and the head office in Europe. We describe how the real-time systems were implemented for a number of global drilling operations without installing a real time operation center. A case study of implementation in one area is presented.
This approach enabled the decision makers in the field to access the experience of and support from the rest of the organization. The global real time collaboration environment allowed the specialists to direct their attention, as required, to operations most in need of support at any particular time. By not installing a real-time operations center, the organization saved resources and encouraged the local teams to use the analysis tools themselves to manage their operational performance.
The head office organization provided technical and administrative support. It facilitated the design of the workflows and set common standards for the IT and communications architecture. The workflows were essential in order to create a structure for using the software tools within a local drilling team and to make sure that problems were detected as early as possible. The workflows aimed to strike a balance between not allowing early warning signals to be overlooked while giving the operations team the freedom to responsibly manage the operation on the rig. Through the way that the system and the workflows were used on a daily basis, the rig personnel gained confidence that the system was set up purely to support them and for their benefit. The design and the implementation of these workflows utilized industry-leading real time drilling data analysis and drilling support tools.
When difficult operational problems were encountered, by acting as a knowledge broker, the central organization drew from its world-wide skill pool to organize problem-specific multi-disciplinary support for problem-solving, peer review and functional sign-off for program changes. These "on-call" teams ensured that the knowledge of the organization was leveraged and experience shared. It enabled the head office organization to provide resources to assist in following up the analysis of positive and negative events will be done properly and result in lessons learnt and updated best practice.