bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geomechanics Enables the Success of Horizontal Well Drilling in Libya: A Case Study
Authors: Qiu Kaibin , Felgueroso Julio Gonzalez , Lalinde Gabino , Naas Abdulmagid , Coste Bernard , Fuller John 
Published: March 2008

AbstractDrilling highly deviated or horizontal wells can be prone to instability problems. This paper describes a case in Libya on which significant difficulties were encountered during drilling the first horizontal development well in a field in Murzuq basin. The first two branches of the well were lost due to severe instability problems.A comprehensive geomechanics study was carried out to understand the causes of the wellbore failure and to improve drilling design and drilling performance on further development wells in the field. The study specifically included: ■Performing a systematic data audit and integration to identify specific uncertainties in the input data and identify data gaps.■Performing a comprehensive drilling event review to investigate what happened during drilling and what were the major instability problems. All drilling events were organized, categorized and input into a database. A graphical presentation of the drilling events review was generated.■Applying a fit-for-purpose stability model. This simple model is driven by easily accessible input parameters and provides a rapid answer.■Validating a Mechanical Earth Model through history matching. This procedure reduced the uncertainty of the model and the resulting wellbore stability predictions.■Applying innovative visualization and presentation of wellbore stability analysis. This improves understanding and awareness of the various drilling hazards and enables effective utilization of the wellbore stability information during drilling.The analysis identified the cause of wellbore instability, as being inadequate mud weight while drilling the overlying shale formation in the deviation build-up section. The design of the second horizontal well was optimized based on this study. The well was drilled successfully without problems and, in fact, ahead of drilling schedule. This case demonstrated that a comprehensive geomechanics analysis can greatly improve drilling performance and reduce drilling costs.
Effects of Boundary Conditions and Friction on Static Buckling of Pipe in a Horizontal Well
Authors: Gao Guohua , Miska Stefan 
Published: March 2008

AbstractA comprehensive buckling model, a group of fourth order non-linear ordinary differential equations, was derived by applying the principle of virtual work. Lateral friction force is included in this model. The equations were normalized to make the solutions independent of the wellbore size, type of pipe and mud. The critical sinusoidal buckling load of tubing with different boundary conditions typically seen in drilling and well completion applications was analyzed based on the analytical solution of the linearized buckling equation. The results show that the effect of the boundary conditions can be neglected when the dimensionless length of tubing is greater than 5π. The authors further investigated the effects of friction on sinusoidal buckling by applying the principle of virtual work. The critical conditions for initiating sinusoidal buckling were determined by a group of three non-linear equations. A perturbation solution of these non-linear equations was obtained. It was found that the critical loads for sinusoidal buckling will increase by 30% to 70% for friction coefficients between 0.1 to 0.3. The authors also conducted an experimental study. The experimental results, including both data obtained by the authors and results published by other researchers, support the proposed model.
Development and Testing of a Rig-Based Quick Event Detection System to Mitigate Drilling Risks
Authors: Aldred Walt , Hutin Remi , Luppens John C.(Chris) , Ritchie Graham 
Published: March 2008

Abstract
High accuracy, speed, and a low false alarm rate are critical to the success of event detection systems and the reduction of non-productive time (NPT) due to unplanned events. The balance between them has been difficult to achieve; however, the application of a probabilistic approach with the use of Bayesian methods has shown significant promise. The results of a research prototype for kick detection using such methods were described in a previous paper (Hargeaves, Jardine, Jeffryes, 2001). The improvements in automated signal processing technology and increased computer power have meant that these new approaches to large scale data analysis in real time are now more widely possible. This paper describes the extension of this work to develop a rig-based quick event detection (QED) system for mitigating a number of common drilling risks, including kicks, circulation loss, and drillstring washout detection.
The QED software application runs on a standard standalone PC at the wellsite and continuously calculates the probability that an event is occurring. The probability changes as an event occurs, which may trigger an alarm. The system continues to evaluate the event as the real-time data is updated and this evaluation provides the drilling team with a continuously evolving probability that the event is occurring. This system helps the team make timely, informed decisions. The system requires minimal hands-on interaction to set up and uses data input via WITS for flow-in and flow-out measurements from typical rig sensors.
The detection of drilling problems in real time using the QED software on several Integrated Project Management well construction projects is presented, including the lessons learned from deploying the technology in field operations.
The significance of this development is to mitigate drilling risks during well construction projects, where minimizing NPT due to unplanned events is critical to success.
Successful Application of Casing-While-Drilling Technology in a Canadian Arctic Permafrost Application
Authors: Vrielink H. , Bradford J. S. , Basarab L. , Ubaru C. C. 
Published: March 2008

Abstract
The JV operator was looking for a combination of technologies to optimize drilling in Canada's Mackenzie Delta region. The area is characterized by a permafrost section up to 2,000 ft (609 m) thick. This shallow permafrost section is dominated by unconsolidated silt with freshwater ice ranging from 60% volume to pure ice layers. Historically, mechanical heat input has melted the frozen layer, resulting in increased hydrates/shallow gas risks, extreme hole enlargement/cleaning problems, rig support issues, wellbore instability, stuck pipe, hydraulic isolation, and environmental impact issues.
Optimizing drilling operations through the shallow section is critical to maximize the number of wells that can be drilled with the available rigs in this limited-access area. To move the rig requires approximately 3 ft (1 m) of ice cover, which significantly limits the operating season, increasing the need for rig efficiency and reduction of non-productive time (NPT). The industry has endorsed the importance of mud cooling through the shallow permafrost and the underlying hydrate-bearing formations to avoid borehole instability and to control hydrate dissolution. However, the industry has struggled to maintain sufficiently cold mud at the high pump/power rates required to effectively drill/clean the larger surface holes.
To solve the challenges, the operator utilized a casing-while-drilling (CwD) and casing bit system with a unique-to-the-industry mud-chilling technology and a variety of controlled drilling parameters. The CwD and casing bit system allowed the operator to drill and set casing through the problematic zones in one operation with relatively low flow rates to avoid hole enlargement. The lower flow rates also enabled the use of smaller, lighter rig equipment that reduced the required ice thickness to move the rig and therefore increase the winter season operating period. Following the successful implementation of the CwD and casing bit system on the first well of a winter program, the second well was drilled safer with the elimination of a casing string, which further reduced drilling time and cost.
Managing the Retrieval of Triple-Zone Intelligent Completions in Extended-Reach Wells Offshore California
Authors: Izquierdo L. , Ceccarelli T. U. , Hertfelder G. P. , Koerner K. , Pace S. 
Published: March 2008

Abstract
An independent operator in offshore California has successfully achieved triple-zone intelligent well completions in an extended-reach drilling (ERD) campaign in its Rocky Point field. To date, two workover interventions have been performed in a total of five deployments in the field, of which three are currently fully operational.
The Rocky Point reservoir is a highly fractured carbonate and can rapidly initiate water production. Achieving zonal isolation in the wellbore and at the reservoir level is critical.
During the production stage it was recognized that two of the wells did not achieve the required zonal isolation evident by increasing water cut. Thus, the operator made the decision to retrieve these completions to conduct liner cement repairs.
These triple-zone completions are controlled by 3½-in. tubing-retrievable flow-control valves, open/close and multiple-position, that work with dedicated gauges for monitoring of pressure and temperature. Each of the productive zones was isolated by three multiple-port retrievable production packers. The main challenges in retrieving these completions were: –Conveyance of the cutting tools to depth (due to ERD profile);–Accurate location of the cutting targets (+/- 6 inches at 18,000 ft MD);–Severing all control/electric lines and pulling all 3 packers in the same trip;–Redressing and re-running the completions within 2 weeks of retrieval.
This paper describes the feasibility of deploying explosive jet cutters by pumping wireline conveyed assemblies to locator profiles above each packer, which allowed for simple, cost effective intervention, avoiding costly mobiliziation of tractors or coiled tubing. Lessons learned are shown on how completions components were affected by the cutting operation and the extent of their refurbishment before re-completion. The paper also identifies some modifications to intelligent completion design parameters (eg minimum distance of control valves from packers) that will be implemented in future installations.
Intelligent Well Completions System Integration Test Mitigates Risk
Authors: Coludrovich Earl , Pace Shawn , Brady Sam , Campo Craig 
Published: March 2008

Abstract
Completions in deepwater sub sea applications are becoming increasingly more expensive and complex. This complexity is compounded by the challenges of installing intelligent completion equipment in deepwater environments. Reliable completions are a direct result of how well the pre-planning and procedures are implemented. The Industry is challenged to integrate multiple service provider equipment and procedures into a single intelligent completion system. Intelligent Well Completion System Integrity Tests (IWC SIT) are being utilized as a proactive means to mitigate risk. This is especially true in international operations where the logistics and planning have a greater degree of complication for completions. This paper is an overview of an IWC SIT conducted in March 2007 for a West Africa deep water field. The write up is a discussion of the planning, implementation, and learning captured for the operation. Highlighted in the paper is a series of subassemblies as run and retrieved from a land rig location. Actual down hole equipment was utilized. Service provider personnel employed for the operation were also the technicians expected to run the equipment on the deepwater rig. A formal report and video were developed to share lessons learned and best practices with the Project Team. The operation was considered successful due to the efforts of a number of service providers, partners, and operator company personnel. A strong commitment to safety, learning, and improving the operations was demonstrated by all involved.
Subsea Production Enhancement—Success and Failure Over Five Years
Authors: McGennis Eamonn 
Published: March 2008

Abstract
Subsea well intervention has been around in the North Sea for many years as documented in papers such as Pollock (1990) but in the last five years there has been renewed interst due to a combination of high oil price and aging wells. This paper will look at the actual results achieved with production enhancement work done in subsea wells across the United Kingdom (UK) sector of the North Sea over a five year period 2002 to 2007. This time frame allows the results to be seen in the context of longer term field value. All the work included in the paper was done rig-less with a specialist subsea well intervention vessel. It covers a range of different oil producing fields operated by a number of different companies. The work done was through tubing and included zone isolation and re-perforation. No work was done in any gas fields. The paper will detail the production profiles of the wells both before and after the intervention work along with a discussion of the work done and an explanation of the factors that influenced the final result both good and bad. To facilitate an open discussion of the success and failures all data is presented anonymously. The high cost of subsea wells makes it essential to maximise the overall recovery per subsea well. This paper will detail actual results which may point the way forward.
New Equipment Designs Enable Swellable Technology in Cementless Completions
Authors: Rogers Hank , Allison Dave , Webb Earl 
Published: March 2008

Abstract
In the oil and gas industry, it is a common practice to install production casing through producing formations, with cement providing the primary inter-zonal isolation in the annulus. However, inadequate displacement efficiencies, fluid contamination, and loss circulation intervals sometimes limit the ability of a cementing operation to provide zonal isolation sufficient to prevent annular communication over the life of the well. Formation damage caused by cementing operations can also adversely affect life-of-the-well production capabilities, thereby adversely affecting the economics of the well.
New completion technologies using swellable elastomers can offer an alternative to cementing operations performed over producing formations. However, conventional floating equipment has limited the application of swellable elastomers in some completion operations. For example, in noncemented completions where swellable elastomers provide the only annular barrier, a mechanical seal having a service life equal to the life of the well under downhole conditions is required at the toe of the production casing.
This paper describes the benefits of swellable elastomers used to provide life-of-the-well zonal isolation. Additionally, the paper recounts a problem job in which improperly selected check valves were used and new check valves specifically designed for noncemented completions were successfully introduced.
Lastly, this paper provides details about equipment designed for a south Texas well that will incorporate SEPs, float equipment, and a combination wiper plug designed specifically for a noncemented completion to be performed in late 2007 or early 2008.
Environmentally Friendly and Economic Waterflood System for October Field at Gulf Of Suez, Egypt
Authors: Ibrahim Mamdouh M , Styler James W , Shamma Hesham L , Elsherif Mamdouh A , AboElalla Essam M 
Published: March 2008

Abstract
October field is one of the major fields in GOS Egypt operating at 100,000 BFPD using 185 MMSCF gas lift injection gas though 50 active producing wells and 11 injection wells with 2 water source wells. Most of the resrvoirs are waterflood. October field is located 21 miles from the west shoreline in the Gulf of Suez.
With time, the performance of the producing wells showed a significant decline in productivity which was attributed to reservoir pressure decline. So, a study was done and resulted in selecting a waterflooding technique for reservoir pressure maintenance and increase of the oil recovery factor.
The economic success of a waterflood project depends on the additional oil recovery it can achieve relative to increased cost over primary development. it must aso be operated in an environmentally friendly manner.
The water source chosen for a waterflood project is usually based on a number of different factors, such as scaling tendency, rock/fluid compatibility, and possibility of bacterial activity. It is possible that a combination of sources could eventually be used. At the location of the waterflood project there may be a number of alternative water sources such as, seawater and separated formation water. Water taken from the sea and separated water associated with produced oil generally need extensive chemical treatment and expensive facilities. Would the project still give this added cost?
The October field waterflood uses a pure water productive zone for source water, which is then injected into the reservoir by two methods:
Water is produced from Zeit formation at depth 3000 ft by ESP and injected directly into water injection wells located on several adjacent platforms, without any chemical treatment. This was possible because the two waters (formation and injection water) were found to be compatible. Dumping water from the Zeit source formation directly to the oil productive zone in the same wellbore by pressure difference, otherwise known as dump flooding.
This technique has an economic advantage over conventional injection schemes by eliminating the need for source water treatment, since the provided water was found to becompatible with flooded reservoir water, formation clays, and rock matrix. It is significantly reduces facility and flow line requirements and saves deck space offshore, and also reduces environmently impact.
Safe, Effective, and Trouble-Free Rig Start Ups—Chance or Good Planning?
Authors: Cormack Dave , Richardson Ross , Steel Tamzin , Watkiss Richard 
Published: March 2008

Abstract
The successful start up of a rig is key to the ongoing success of a drilling contract for both operator and contractor alike. Good performance can only be achieved through competent, highly motivated and safety conscious people. Therefore, getting the HR, HSEQ & Training elements correct at the outset cannot be left to chance and good fortune but must be the result of integrated cross functional planning amongst a number of key stakeholders.
One drilling contractor had gained experience starting several major projects across the world in recent years and had developed a methodology for the ideal rig start up using a cross functional project approach. As part of its strategic growth plans, in 2007 it was going to start-up in excess of 20 very diverse rig operations over the twelve month period. Achieving success in growth of this size, speed & variety could not be left to chance but had to be as a result of good planning.
This paper will discuss how that organisation took the lessons it learned in the past and applied them in a structured manner via its Corporate HSE plan to ensure each and every start up was Safe, Effective & Trouble free. The paper analyses the successes and failures of various start ups across the organisation and demonstrates that the more involvement HR, HSEQ & Training had in the early stages the more successful the overall start up was. This was particularly true when involvement formed part of a structured and integrated plan in conjunction with all stakeholders including clients.
Given the projected volume of new work across the industry over the coming years, along with the recognised shortages of experienced personnel available, this fully integrated approach to starting up new operations is highly significant in today's drilling industry.
Expandable and Contractable Drill Bit-A Novel Technology for Hole Enlargement
Authors: Agarwal Sharad Ashok , Agarwal Navin 
Published: March 2008

Abstract
Expandable and Contractable drill bit is a new concept in bits which will allow us to drill super wide boreholes with radii of our choice and at depth of our interest. It will allow us to drill increased diameter borehole, having passed through restricted casing and/or tubing diameter and can provide significant advantages. Among these is the ability to incorporate novel well construction techniques, using both solid and/or expandable tubular, as well as drilling with Casing possibilities, in which casing is run immediately behind the bit. The opportunity to incorporate these techniques can thus enhance well design to yield significant economic and well control gains. Current techniques for drilling such increased diameter holes, such as bi-centered bits and under-reamers, have limitations on their ability to expand, whilst at the same time compromising the cutting structure presented to the formation. Additional limitations include limited reaming and back-reaming capabilities, as well as non-directional response. One embodiment of the technique of Drilling with Casing requires a bit which can be retrieved through existing casing string. To achieve this and to maximize drilling performance requires a device with a formation cutting structure, indistinguishable from a standard PDC drill bit but capable of being withdrawn through a restriction significantly smaller than the borehole size just being drilled. This concept leads to the possibility that a viable solution to the task of drilling increased diameter holes could be a bit that offers substantial expansion and contraction while still presenting full cutting structure to the formation.
In this paper the authors will discuss the earlier problems and solutions and present a new approach with an "Expandable and Contractable Drill Bit". They will discuss the design concept of bit, working, advantages, challenges and finally will conclude that the use of an "Expandable and Contractable Drill Bit" will be a viable tool for variety of drilling applications.
Auto Release Drill Collars
Authors: Agarwal Sharad , Agarwal Navin 
Published: March 2008

Abstract
The drilling industry is currently exploring various ways of reducing costs through multitude of initiatives. One of the major areas where there is potential for cost reduction is downtime due to drill string failures. Differentially stuck pipe (DSP) occurrences are common everywhere, and account for a significant amount of non-productive time and ends up as one of the major causes of increased well costs. In some areas, events related to differentially stuck pipe can be responsible for as much as 40% of the total well cost. The risks if DSP increases when drilling depleted reservoirs, and, due to the low profitability of such projects, any undesired event could hurt the economics of these developments.
Even though this is an old problem, with new drilling technologies, especially related to the use of drill collars, which is one of the main component of down hole assembly which in 60% of cases gets stuck, therefore there is a need to redesign the drill collars which can be able to drill ahead even in case of depleted reservoirs without getting differential stuck. In this paper, a new solution to DSP has been proposed. In addition, field cases are presented describing what the losses due to DSP are; the best option to reduce the risks of DSP is suggested. A simple drill collar is designed in such a way that the surface area of the drill collar is not is contact with the depleted reservoir or mud cake which is built up at the side of the wall. The drill collar is designed in such a way that it does not get differential stuck, can drill ahead and easily retrieved even in depleted reservoirs or in case of thick cake built at the side of the well bore wall. This technique will eliminate many of the conventional stuck pipe problems allowing for easier and fasten drilling, thus saving rig time and ultimately economics of the entire operation at a fraction of increased cost in the new drill collar.