bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Pipe Rotation on Hole Cleaning for Water-Based Drilling Fluids in Horizontal and Deviated Wells
Authors: Ozbayoglu M. E. , Saasen A. , Sorgun M. , Svanes K.
Published: August 2008

One of the major concerns during drilling horizontal and directional wells is proper hole cleaning. If there exists a stationary bed, generally, an increase in the fluid velocity will erode the bed significantly. However, depending on the drilling conditions, very high fluid velocities are needed for bed removal, which may not be applied due to hydraulic and physical limitations. In such cases, pipe rotation may enhance the cuttings transport mechanically, and effective hole cleaning can be achieved even at fluid velocities lower than the critical annular fluid velocities required to prevent stationary bed development. In this study, the effect of pipe rotation on hole cleaning is investigated for horizontal and directional wells. Cuttings transport experiments have been conducted at METU Cuttings Transport Flow Loop using pure water as well as water-based muds consist of different concentrations of xanthan biopolimer, starch, KCl and soda ash, weighted with barite. Effect of pipe rotation have been observed for hole inclinations from horizontal to 50 degrees, for rate of penetrations from 15 to 45 ft/hr, for flow velocities from 2.1 ft/s to 7.2 ft/s, and for pipe rotations from 0 to 120 rpm. Pressure drop within the test section, and stationary and/or moving bed thickness are recorded besides the other test conditions. It has been observed that, pipe rotation has a significant improvement on cuttings transport, especially if the pipe is making an orbital motion. Also, pipe rotation drastically decreases the critical fluid velocity required to remove the stationary cuttings bed totally. However, after a certain rotation speed, no additional contribution of pipe rotation on hole cleaning is observed. When there are no cuttings present, the frictional pressure losses are increasing as the pipe rotation speed is increased. However, as the cuttings are introduced, due to the reduction in the stationary cuttings bed area, frictional pressure losses may decrease. Additionally, the effect of pipe rotation on hole cleaning as a function of fluid viscosity is also examined. It has been observed that, as the fluid viscosity is increased, contribution of pipe rotation on hole cleaning is increasing when compared with no rotation case.
Validation of Blowout Rate Calculations for Subsea Wells
Authors: Oudeman P.
Published: August 2008

Calculating the blowout rate of oil and gas wells is commonly one of the first steps in environmental impact assessment, contingency planning and emergency response. The blowout rate is a direct measure for the economic and environmental damage caused by a blowout and an indicator for the effort required to regain control over the well. Hence a simulator was developed to estimate blowout rates.

This simulator was validated for field cases by comparing calculated blowout rates with estimates based on observable phenomena such as flame length and heat release rates. This limited validation to onshore and platform well blowouts, which are usually governed by critical outflow conditions at surface, i.e. ambient pressure is considerably less than the wellbore pressure just upstream of the outflow. For subsea wells, blowing out against the substantially higher pressures at seabed, this does not apply. The blowout rate is determined by the total system performance from inflow at sand face to outflow at seabed. To validate the blowout rate calculations under these conditions, data were collected on high rate well flow through an annulus against elevated surface pressures, resembling subsea blowout conditions. A comparison of the measured rates with the calculated rates demonstrated that the rates could be predicted with a high accuracy, provided the mechanical condition of the tubulars is properly taken into account. Default assumptions for the hydraulic roughness of the tubulars lead to over-estimates of the blowout rates and consequently worst case estimates for the environmental and economical damage caused by a blowout.
New Techniques Accurately Model and Plan 3D Well Paths Based on Formation's Deflecting Behaviors
Authors: Liu Xiushan
Published: August 2008

Accurate well-path planning is the prerequisite for operators to drill directional or horizontal wells successfully. During directional drilling operations, bit walk objectively exists along an actual drilled well trajectory. Drilling experience shows that it is an effective measure to control a well trajectory by taking the physical bit walk into account if the rate of bit walk can be accurately estimated. As the planned results of bit-walk path can evidently reduce the frequency of azimuth correction and drilling-string trips, and lessen the difficulty and workload of trajectory control, it will undoubtedly improve the rate of penetration and the quality of well trajectory, and cut down the cost of drilling.

The author has published some related methods to plan 3D bit-walk paths, in which the bit-walk rate must maintain constant over each well-path section (build-up, hold-up or drop-off). In some cases, the bit-walk rates are given on the basis of rock characteristics. In addition, it is also an effective measure to determine an appropriate wellhead location, if there is no limitation of surface condition, for the desired profile of a horizontal well. This paper makes further researches on the mathematical model of bit-walk path and gives more concise formulas, analyzes the compositive relation of inclination units and azimuth units, and yields a method to divide them into shorter intervals for calculation. The author discusses the characteristics of planning bit-walk paths and presents the constraint equations and solutions for directional wells. For the desired profile of a horizontal well, this paper also describes the idea and techniques to accurately determine the surface location and a key parameter of the profile, such as KOP, accounting for bit-walk effects. The model and methods provided employs exact mathematical solution and results, and the planned paths are smooth from the wellhead to the given target.

The methods proposed represent significant improvements over the traditional well-path planning techniques, and were programmed into computer software. Several examples are given, and the results proved satisfactory for various directional and horizontal wells.
Field Implementation of Sub-Surface Waste Injection: An Integrated Approach for Field Disposal Perspective
Authors: Ovalle A. , Shokanov T. , Simmons S. , Ronderos J.
Published: August 2008

As the world faces new challenges to protect the environment from all human-generated wastes, self-imposed industry policies as well as governmental regulations support new green policies towards implementing best, not necessarily least costly, practices to prevent any environmental damage due to spillage during operations. Waste Injection (WI) has been selected as the preferred methodology of final disposal of oilfield wastes, including cuttings, produced water, drilling fluids and tank bottoms, etc., by many operators and legislators because it achieves zero discharge in a safe and efficient manner at a lesser operating cost than comparable proven technologies. This may be particularly true for large-scale projects. Mexico, Argentina, Azerbaijan, USA, UK, Norway, Russia and other countries have strategically implemented WI operations in field developments because they comply with local laws and they avoid future liabilities as wastes are permanently isolated and stored below surface.

The development and implementation of such technology in large-scale projects is carefully designed using a risk-based analysis that is comprised of fracturing studies of the area of injection, technologies integration, logistics, equipment specification and process monitoring, all with the aim of performing a seamless and risk-free operation. The following paper addresses planning and implementation methodology for WI operations with real examples that demonstrate the value of proper preparation and integration of various technologies to attain maximum efficiency under QHSE standards.
Well Productivity and Oil Recovery Enhancement in East and West Siberian Fields as a Result of Inflow Control Technology and Application
Authors: Zaikin Igor , Kempf Konstantin Victor , Voll Benn , Budlov Sergey , Laidlaw Duncan
Published: August 2008

A major Russian operator has encountered operational risks and challenges in oil production due to the highly diverse reservoir properties of Siberian fields. The majority of the operator's east and west Siberian fields include heterogeneous sandstones with low to high permeability, complicated geological and stratigraphic cross-sections and an active bottom water aquifer. In some areas, a gas cap is one of the drive mechanisms.

Horizontal wells tend to become more popular in both green and brown fields because of improved recovery efficiency due to increased reservoir drainage area. However, unbalanced inflow profiles along horizontal sections can result in early water/gas breakthrough which shortens well life and decreases overall profitability.

This paper will describe the application of inflow control technology in two Siberian fields (one with a sand control issue), addressing early water and gas breakthrough caused by intensive water injection and a massive gas cap. Production is optimized by ensuring uniform inflow profile along lateral sections and minimizing annular flow. The setting selection process for inflow control devices and the integration of reservoir analysis with well completion are detailed. The resulting delay of water/gas breakthrough in these horizontal wells leads to enhanced recovery efficiency and improved productivity.
OMV—Benchmark for 8-1/2" Hole Section with One Bit in Sawan Field of Pakistan
Authors: Preining Peter , Khan Asif M. , Ali Muhammad , Syed Mustafa
Published: August 2008

OMV Pakistan applied an original design of Genesis XT fixed cutter bit with improved features for bit stability to drill the 8.5″ section of Sawan-11 development gas well in southern Pakistan. Multiple vertical wells were drilled in this field with similar parameters and operating conditions. Latest proven technology was applied successfully to drill the 1760m of 8.5″ section with record ROP of 25 m/hr which is more than twice as fast compared to previous wells records. Instantaneous rates in excess of 70 m/hr were also recorded while drilling this section. This section was previously drilled with multiple bit runs using multiple roller cone and PDC bits. Later, this was reduced to 2-3 PDC bits and now the complete section has been drilled with one PDC bit (HC 606Z). Dull grading comparison with bits used in the offset wells will also be discussed. The lithology of the drilled section consists of Ranikot formation (dominating claystone with inter bedded sandstone and siltstone). Throughout this zone bit stability and optimized drilling parameters of the bit were key factors affecting its performance. Below this zone Upper Goru (UG) and Lower Goru (LG) formations are found. UG Member mainly consists of marl with streaks of limestone having an UCS of > 35 kpsi in its contact with the Ranikot formation. This type of formation is generally the most difficult to drill. LG Member comprises of claystone and siltstone with occasional traces of pyrite having UCS of 20-25 kpsi. Towards the end of section, last 400m witness increased percentage of abrasive siltstone which affects cutter's sharpness and reduces the ROP. Offset data conforms that around this point bits quit drilling. However, at Sawan-11 bit maintained its sharpness and good ROP till the end of this section.
Delivering Steering Success in Problematic Soft Formation Directional Wells
Authors: Barton Steven , Card Kirk , Pierce Garrett
Published: August 2008

Development and diversification of directional drilling tools continues, as do the applications in which they operate. As a result, there is continual demand for development and refinement of drill bits and string tools to meet the latest challenges and issues faced. One such challenge is the ability to reliably deliver consistent directional performance in very soft formation applications. Issues such as hole washout, inappropriate drilling parameters, stabilization, and hole quality can all contribute to poor directional drilling performance.

Several commercial projects are reviewed where technical merit has justified use of Rotary Steerable Systems (RSS), but due to the very soft lithologies, these systems have been unable to deliver the required directional control. In each example, a separate engineered solution is introduced. These include; An innovative concentric string reamer, featuring a mid-reamer section that enables effective stabilization of the reamer even if the pilot borehole is of poor quality or is over gaugeA soft formation fixed cutter drill bit design with an engineered hydraulic configuration to avoid hole washout and extended circumferential gauge geometryA near-bit stabilizer incorporating a full ring gauge that delivers 360 degree circumferential coverage, thus providing greater contact with the wellbore and higher potential for deviationA specific Bi-center design that utilizes a secondary component configuration on the face of the pilot to enable appropriate drilling parameters to be utilized for efficient directional control. The gauge geometry and profile is also tailored to suit soft formation drilling.

Global case studies document where these solutions, in combination with both Push and Point RSS, have proven extremely successful. These have provided greater flexibility with regard to tool selection, well planning options, and delivering lower cost per foot in RS projects.
Fluctuation of Equivalent Circulating Density in Extended Reach Drilling with Repeated Formation and Erosion of Cuttings Bed
Authors: Naganawa Shigemi , Okatsu Komei
Published: August 2008

Management of equivalent circulating density (ECD) is one of the key issues in designing and drilling extended reach well (ERW). The paper focuses on ECD fluctuation occurred while repeated formation and erosion of cuttings deposit bed in drilling ERW. Numerical studies of hydraulics calculation were carried out in combination with cuttings transport model along the whole trajectory of ERW. While the cause of ECD fluctuation is primarily thought to be the mud pumps being turned on and off, our calculations showed that repeated formation and erosion of cuttings deposit bed, due to the repetition of drilling and drilling interruption for making a connection, causes a significant level of irregular fluctuation of ECD. To avoid severe unexpected ECD fluctuation in drilling ERW, the authors recommend that the schedule of mud circulation operations for hole cleaning and ROP management should be carefully designed by hydraulics calculations in consideration of transient behavior of cuttings transport.
Wireline Tractor Technology Supports Fast Tracking New Well Design
Authors: Shiong Lam Fei , Collins Joseph Paul , Schwanitz Brian
Published: August 2008

As well completions are becoming more and more complex, alternatives to traditional well intervention technologies surface.

A way of optimizing mechanical interventions, while also providing a value-creating alternative, is the utilization of established down hole wireline tractor technology. The manipulation and/or replacement of down hole hardware components in conjunction with wireline stroker and wireline key (intelligent shifting tool) applications makes it possible to perform reliable, economical, and flexible interventions such as opening/closing sliding sleeve doors (SSD) or valves, setting and retrieving plugs, straddles and gas lift valves (GLV), even in horizontal and extended reach drilled (ERD) wells.

Various successful applications in the industry of this down hole shifting system proves the reliability and practicability of these technologies as a cost effective alternative to traditional intervention methods.

One example was the successful application of a tool string combination comprising of a wireline tractor with a stroking tool and a key tool used to close a 5-1/2" SSD located in a section of the well at more than 70° angle in the midst of various operational constraints including tight allowable deck space, allowable personnel-on-board (POB) and allowable project time frame. Despite these challenges, the entire operation saved the operator 4.5 days and approximately USD 650,000 in costs as compared to traditional intervention methods.

Another example was the successful application of the wireline tractor and wireline stroker in a newly drilled well being prepared for production from three of the production zones in the reservoir. The wireline tractor and wireline stroker successfully sat a deep set plug, shifted close an SSD and retrieved the deep set plug with zero personnel injury and zero hour lost time.

Third example was the application of the wireline tractor and wireline stroker to repair a well completion in an old producing well by isolating a stuck SSD with a 22-meter multi-section straddle and then isolate holes in the tubing with an 8-meter single straddle. Well optimization was remarkable with Q oil increased by 900% and water cut reduced from 85% to less than 5%.

With the wireline tractor, wireline stroker and wireline key tool technology, and the case histories that prove the reliability and advantages associated to these technologies, well and completion designers' creativity are now less restricted by the concerns of the feasibility and economical constraint of future well interventions in highly deviated, horizontal or ERD wells, thus fast tracking of new well designs is possible.
A New Mud Pulse Telemetry System Reduces Risks When Drilling Complex Extended Reach Wells
Authors: Klotz C. , Kaniappan A. , Thorsen A. K. , Nathan E. , Jahangir M. , Lie L.
Published: August 2008

Mud Pulse Telemetry (MPT) is the most common down hole-to-surface communication technology utilized by MWD/LWD systems. Compared to alternative technologies, MPT systems are characterized by a proven record of high reliability in a wide range of operating environments. Reliable data delivery is feasible in a variety of scenarios ranging from shallow vertical to complex, deep water wells in all types of drilling fluid media.

Recent years have seen the introduction of many new LWD technologies which are providing unparalleled amounts of wire line quality evaluation data in realtime. Access to high quality, complete, evaluation data sets whilst drilling is enabling geologists and engineers to make decisions with higher confidence based on more and higher quality datasets, consequently enabling wells to become more complex and fulfill multiple objectives. The ever increasing volume of information generated by these new technologies has begun to exceed the bandwidth transmission capacity that traditional MPT technology can deliver. To fully capitalize on the LWD technological advances being implemented, an increase in data transmission speeds is required.

This paper discusses a new telemetry system that delivers data rates in excess of 6 bits per second (bps). The system has been deployed in a number of complex 3D extended reach offshore wells in Norway. During operations, the system reliably delivered high data rates of up to 20 bps, resulting in improved drilling efficiency, and reduced operational risk due to enhanced realtime decision quality based on the improved quality of FE and downhole diagnostics data.
New Steel Tooth Cutting Structure Breaks Multiple Records in Australasia
Authors: Bunton Steve , Sim Natalie , Grimes Bobby
Published: August 2008

Approximately 90% of the large diameter holes in Australasia (Indonesia, Australia, PNG and New Zealand) are drilled with steel tooth roller cone bits. A new steel tooth bit design has proven to significantly improve the drilling economics in these applications. This paper describes the drilling challenges posed by these applications, details the new bit design features, and presents case studies showing the performance improvements these new bits provide when compared with conventional steel tooth bits.

The new design bits feature a novel cutting structure with pyramid-shaped teeth, additional rows of teeth, wide grooves between rows, anti-tracking row(s) with tight pitches, thick hardfacing deposits, and a bar trimmer type gauge design. The result is a steel tooth bit that delivers significantly higher ROP and longer life than current designs, with high reliability, and predictable steering behavior for directional applications. Hole sections can often be completed with fewer bits, which further improves drilling economics. These bits achieve ROPs faster than even that of large diameter PDC bits in the Australasian applications, thus the reason that steel tooth bits are primarily used.

An operator in Balikpapan, Indonesia drilled a long S-shaped hole with a new 17 1/2-in. steel tooth bit at 40% higher ROP than the best of nine direct offsets that were drilled with conventional steel tooth bits. Another operator offshore Western Australia conducted a head-to-head comparison of a new 16-in. steel tooth bit against a conventional steel tooth bit in identical hole sections. The new bit drilled over 70% faster and over 25% farther than the regular bit. A third operator in the Northwest Shelf area off Western Australia employed a new 17 ½-in. steel tooth bit to complete a section normally drilled with 12 ¼-in. PDC bits. The new steel tooth bit drilled over 25% faster than the fastest PDC offset run. Additional case studies will be presented further documenting these positive field results.
Evolution of Innovative Test Methodology for Evaluation of Hardfacing Materials in both Cased and Open Hole Environments
Authors: Chan Alvaro , Hannahs Dan , Waters Scott
Published: August 2008

Extensive development has been made in the field of wear evaluation of hardfacing materials for downhole applications. These improvements have been industry driven to optimize drilling operations and reduce cost. Previous testing methods such as DEA-42 presented multiple hardware and process deficiencies which recorded results which were inaccurate, unreliable and not repeatable. An evolution of both hardware and processes for hardfacing material testing was developed over a 36-month period through laboratory testing and data evaluation.

This new methodology has been applied to the evaluation of hardfacing materials in both open and cased hole environments. Not only does it provide more reliable data, it also provides the flexibility to test different fluids, casing grades and varying open hole media. Actual material properties such as friction factors and wear rates have been successfully and accurately measured. It has also been used to identify break-in periods for different hardfacing materials.

The methodology has demonstrated repeatable and accurate results for wear characteristics for hardfacing materials under various conditions. Multiple hardfacing materials have been evaluated and their performance compared through this methodology. This methodology greatly surpasses previously established and outdated industry standards. This methodology was employed to engineer and develop a fourth-generation casing friendly hardfacing material currently in service.

This novel approach provides reliable wear characteristics data for available hardfacing materials. It provides a benchmark for industry evaluation of hardfacing materials previously not available in the industry. The use of this technology will aid in the development, selection, and performance evaluation of hardfacing materials for modern and complex well programs. It will improve downhole drilling performance by providing better selection of hardfacing materials.
Deep Salt Formation Wells Successfully Drilled with Integrated Techniques in Tahe Oilfield
Authors: Zhong Liguo , Cong Haiyang , Wang Shiqing , Zhao Defu , Wang Zhifeng , Yang Guang
Published: August 2008

The most challenging drilling problems encountered in Tahe Oilfield occurred in the deep salt formations. Most holes lost are caused by stuck drilling strings, stuck casing, and collapsed casing because of the special salt formations. Particular research is conducted to solve these problems. At first, the occurrence arose in salt formations are identified in detail. Then the components of typical salt rocks are analyzed, and properties such as plasticity, solubility, stability, and stress sensibility measured, some new techniques evaluated, and integrated techniques developed. As a result of implementation of the integrated drilling techniques, deep salt formations drilling in Tahe Oilfield has been substantially improved.

The main researching results presented in this paper are attached to the discussion of the salt formation problems, laboratory measuring and testing of the salt rock and evaluated techniques, and field drilling application. Integrated techniques recommended are particularized, such as borehole structure, salt water based mud system, expanding drilling and drilling string assemblies optimized.
Working Smarter On Well Intervention Operations
Authors: McNicol Jim , Joppe Bart
Published: August 2008

This paper describes a new intelligent well intervention performance system. One that contains a variety of sensors and electronics to gather critical downhole measurements, analyze them, and transmit them to surface for viewing in real time.

It confirms that many well intervention operations, especially those that get into difficulty, suffer from a lack of accurate information about true downhole conditions, and that actual downhole conditions in deep, high-angle wells differ significantly from what is indicated by traditional physical measurements taken at surface alone. The parameters measured downhole include RPM, torque, tension and compression, stick-slip, bending stress, dogleg severity, and many others.

Extensive field integration testing and early commercial deployment show how downhole tool performance information provides parametric information physically characterizing the true downhole environment. This real time information, never before seen at surface, demonstrates the potential to enable more efficient and more reliable well intervention operations while significantly reducing uncertainty and risk exposure.

Several case histories are presented where the smart tool was integrated into well intervention BHA's and operations were improved by a better understanding of what is really happening downhole.
Casing Drilling Technology as the Alternative of Drilling Efficiency
Authors: Buntoro Aris
Published: August 2008

The drilling technology was developed to increase the drilling efficiency based on 3 basic reasons, i.e.: safety, minimum cost, and usable hole. Casing drilling is one of drilling technology which it has been applied in many oil fields in Indonesia.

The casing drilling is classified into 3 methods, i.e.: Retractable Bit, Liner Drilling, and Drilling with Casing, where each method can be applied in certain condition. Recently, the drilling technology has reached efficiency significantly, both in engineering and economical aspects, especially in the formation which is difficult to drill with conventional drilling method, for examples: ❑Abnormal/subnormal zone❑Thief/loss zone❑Unstable formation

Generally, the drilling efficiency can be formulated based on statistic trend from the field data. Thus, casing drilling can be developed to reach the drilling efficiency according to the field experiences.
Early Detection of Drillstring Washouts Based on Downhole Turbine RPM Monitoring Prevents Twist-offs in Challenging Drilling Environment in India
Authors: A. Daison Paul , Belavadi Mukund N.
Published: August 2008

The rising need for hydrocarbon forces operators to drill more aggressively even in harsh formations and to drill well profiles with ever-increasing directional complexity. As a result, drillstrings are increasingly exposed to tough drilling conditions causing mechanical fatigue due to vibrations and bending stress cycles in tortuous wellbores. Additional challenges are posed by high torque and drag situations, corrosive drilling mud environments, abrasive formations, high temperature, high pressure and other unconventional drilling practices. On the economical side the situation is worsened by limited supply capacity and high prices for new drillstrings, forcing operators to rely on older drill pipes in critical applications.

Mechanical fatigue, corrosion or abrasion makes a drillstring vulnerable to wash-out, allowing mud to flow from the inside of a drillpipe through an initially small leak in the pipe wall into the annulus. If not detected in time, the leak will wash out rapidly and eventually cause a drill string twist-off which can be catastrophic. The result will be significant non-productive time for fishing operations or, in worst case, loss of an expensive BHA or even an entire well section. Presence of radioactive sources in such a situation can compound the problems many fold.

This paper presents a method to detect wash-outs at a very early stage where it is not possible yet to identify the wash-out from classic surface measurements such as stand pipe pressure. This is based on real-time transmission and close monitoring of the rotary speed of a downhole turbine positioned in the MWD BHA close to the bit. The effectiveness of the method was demonstrated recently on a year long period of a drilling campaign in a difficult drilling environment in India. A total of 9 washouts were detected, but not one twist-off occurred on these 9 runs. Not a single washout was found at the surface that was not indicated earlier by a reduction in MWD turbine RPM.

The paper starts with an overview of the washout detection concept and presents several data examples to illustrate the method in detail. The case study from India describes the implementation and the effectiveness of the method that has resulted in a 100% success ratio in washout detection in this application. After this services were introduced to the operator, the operator has made the requirement of washout detection services a standard part of its job planning.
Dynamic Pre-Modeling of MPD Operations Enabled Optimal Procedures and Operations
Authors: Petersen Johnny , Bjorkevoll Knut S. , Rommetveit Rolv
Published: August 2008

Outline

An advanced dynamic flow and temperature model was used to optimize and control MPD operations at Kvitebjørn. This paper describes in detail pre-simulations done to prepare for operations and develop detailed procedures, and post-analysis of real time data done to improve performance with respect to upcoming MPD operations at Kvitebjørn. The paper gives details on: Pre-simulations of drilling operations including temperature effectsExtra offline simulations during operationsPost-simulations with analysis of model-data deviations

Results and observations

The paper discusses in details critical operations with main focus on sequences with multiple fluids in the well. These include setting of a balanced mud pill, tripping out and in with the pill in the hole, circulating out the pill, and cementing. Comparison with data taken when testing in cased hole is discussed, and it is described how good pressure control was obtained in real operations after having drilled into the reservoir.

Applications and conclusions

The paper gives useful input to the use of advanced dynamic models for MPD operations. It gives a good impression of current status as well as possibilities and limitations for future operations.
Dynamics and Torque Considerations Involved in Top Drive Casing Running Operations
Authors: Abrahamsen E.
Published: August 2008

This paper addresses important and largely overlooked challenges that exist when making up premium casing connections with a top drive and it describes how these issues can be controlled. To investigate them, tests were performed both in the Test Lab and in the field to examine the accuracy of torque measuring equipment normally associated with top drive casing make up tools (TDCM) when considering the following situations: ￭ Dynamic Torque – since the TDCM and the top drive are mechanically connected to the top of the casing or tubing joint during make up, their combined rotating mass represents kinetic energy. This in turn adds dynamic torque to the connection being made up when rotation comes to a sudden stop – i.e. when the connection reaches a shoulder contact.￭ "Backswing" – When the applied top drive make up torque is released abruptly, torsion generated static energy stored in the joint accelerates the above mentioned masses in the breakout direction. This translates to kinetic energy which applies breakout torque or "backswing" to the connection which can be significant depending on how rapidly the top drive make up torque is released.

The test results identified these forces conclusively and also lead to the conclusion that standard top drive torque measurement systems are not capable of measuring either of them.

In this paper the author will discuss these torque situations and present the results of the tests performed. He will conclude that both of these torque anomalies do in fact exist and that, though the response time of standard top drive torque measuring systems is sufficient for general drilling operations, it will in many cases be too slow for shouldered connections. He will also conclude that without alternative torque measuring systems the final make up speed of the top drive for premium connections must be drastically reduced to avoid the possibility of damage.
The Pathophysiology of Cardiovascular Disease and Diabetes: Beyond Blood Pressure and Lipids
Authors: Dokken Betsy B.
Published: August 2008

In Brief

The pathophysiology of the link between diabetes and cardiovascular disease(CVD) is complex and multifactorial. Understanding these profound mechanisms of disease can help clinicians identify and treat CVD in patients with diabetes, as well as help patients prevent these potentially devastating complications. This article reviews the biological basis of the link between diabetes and CVD, from defects in the vasculature to the cellular and molecular mechanisms specific to insulin-resistant states and hyperglycemia. It concludes with a discussion of heart failure in diabetes, a clinical entity that demonstrates many of the mechanisms discussed.
Management of Peripheral Arterial Disease
Authors: Steffen Lyn M. , Duprez Daniel A. , Boucher Jackie L. , Ershow Abby G. , Hirsch Alan T.
Published: August 2008

In Brief

Peripheral arterial disease (PAD) is a common atherosclerotic disease affecting the quality of life of > 8 million Americans. PAD is characterized by atherosclerotic stenoses of arteries that supply the lower extremities and is associated with a marked increase in the short-term risk of heart attack, stroke, amputation, and death. Adherence to pharmacological therapies and modification of lifestyle factors, including increasing moderate physical activity along with supervised exercise, smoking cessation, and a healthy dietary intake, are central to the successful management of PAD. The improvement of an adverse cardiovascular risk profile is a proven and crucial strategy to lower the risk of major morbid and mortal events for individuals with PAD.
Prevention and Treatment of Cardiovascular Disease in People With Diabetes Through Lifestyle Modification: Current Evidence-Based Recommendations
Authors: Pereira Raquel Franzini , Franz Marion J.
Published: August 2008

In Brief

People with diabetes are at much higher risk for cardiovascular disease(CVD) than the average population. Evidence-based, prioritized, and strategic management of CVD risk factors among people with diabetes is necessary for the improvement of its burden on disability, morbidity, mortality, and high health care costs. Risk factors for diabetes and CVD are similar, and most can be effectively decreased by lifestyle modification. Medical nutrition therapy and other lifestyle recommendations for CVD prevention and treatment are discussed.
Formations of lattice ordered groups and of GMV-algebras
Authors: Jakubík Ján
Published: August 2008

A class of lattice ordered groups is called a formation if it is closed with respect to homomorphic images and finite subdirect products. Analogously we define the formation of GMV-algebras. Let us denote by ℱ1 and ℱ2 the collection of all formations of lattice ordered groups or of GMV-algebras, respectively. Both ℱ1 and ℱ2 are partially ordered by the class-theoretical inclusion. We prove that ℱ1 satisfies the infinite distributivity law

and that ℱ2 is isomorphic to a principal ideal of ℱ1.
Medium Effects on the Initial and Transition States on the Amine-Catalysed Ring-Opening of Azlactone in Water–Acetonitrile Mixtures
Authors: Ismail Amel M. , El-Sadany Samir K.
Published: August 2008

The kinetics of ring opening of azlactone in water – acetonitrile mixtures in the presence of morpholine have been studied under pseudo-first order condition in the temperature range 40-60°C. Non-linear plots of log kobs with the reciprocal of relative permittivity of the solvent were obtained while linear plots of log kobs against the Y value were observed. The thermodynamic parameters Δ H≠, Δ S≠ and Δ G≠ have been determined; Δ G≠ increases gradually as the mole fraction of the cosolvent increase, due to a complex quasi-mirror image compensation of Δ H≠ and Δ S≠. The negative values of the entropy of activation and the non-linear relation of log kobs with the reciprocal of relative permittivity suggested selective solvation by the more highly polar water molecules. The isokinetic temperature obtained indicated that the reaction was enthalpy-controlled. The presence of an electron-releasing or electron-withdrawing para-substituent in the benzylidene moiety affected the reaction rate, i.e. it being accelerated by p-Br but retarded by p-OMe substituents. Also the rate was decreased by increasing the content of organic cosolvent. The reactivity was analysed in the light of various simple and multiple regression equations using Kamlet–Taft solvatochromic parameters which were applied successfully in mixed aqueous – acetonitrile mixtures.
Picolinic Acid Assisted Three-Electron Transfer Chromic Acid Oxidation of dl-Mandelic Acid in Aqueous Micellar Media: A Kinetic Study
Authors: Islam Monirul , Das Asim K.
Published: August 2008

The three-electron transfer chromic acid oxidations of dl-mandelic acid (MA) in the presence and absence of picolinic acid (PA) have been studied in aqueous micellar media under the kinetic conditions, [ dl-mandelic acid] ≫ [PA]T ≫ [CrVI]T at different temperatures. Under these kinetic conditions, HCrO4- has been found to be kinetically active in the absence of picolinic acid while in the PA-catalysed path, a CrVI—PA complex has been established as the active oxidant. In the PA-catalysed path, the CrVI—PA complex experiences nucleophilic attack by the substrate to form a ternary complex which subsequently undergoes a redox decomposition involving 3e-transfer, leading to oxidative decarboxylation through C—C bond cleavage. This rate-determining step produces CO2, benzoyl radical and the corresponding CrIII—PA complex. Benzoyl radical is subsequently oxidized to benzoic acid in later, faster steps. In the uncatalysed path, the CrVI—substrate ester also undergoes an acid-catalysed redox decomposition through 3e-transfer as the rate-determining step. Both the catalysed and uncatalysed paths show a first order dependence on [H+] and both paths also show a first order dependence on [ dl-mandelic acid]T and [CrVI]T. The PA-catalysed path is first order in [PA]T. These observations remain unaltered in the presence of externally added surfactants. The effects of a cationic surfactant such as N-cetylpyridinium chloride (CPC) and an anionic surfactant such as sodium dodecyl sulfate (SDS) on both the uncatalysed and PA-catalysed paths have been studied. CPC has been found to accelerate the uncatalysed path and to retard the PA-catalysed path. SDS shows a rate-accelerating effect for both paths in different ways.
Mechanism of Oxidation of Aqueous Phenol by H2O2 Catalysed by a Macrocyclic Iron(II) Complex
Authors: Yi Zhang , Jia-qing Xie , Ci Li , Jun LI , Hong-li Shang
Published: August 2008

The iron(II) complex of the macrocyclic ligand 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraaza-cyclotetradecane was synthesized and characterized and used as a mimetic peroxidase in the catalytic oxidation of phenol with H2O2. The mechanism and a kinetic model of the catalytic oxidation are described. The results show: the catalyst as a peroxidase mimic exhibited strong catalytic activity; the main reaction products detected by high-pressure liquid chromatography (HPLC) were catechol, hydroquinone, p-benzoquinone, maleic acid and oxalic acid; the catalytic oxidation of phenol accords with the enzyme mechanism.
A Kinetic Study of the Ru(III)-Catalysed Oxidation of Glutathione by Methylene Blue in Acidic Medium
Authors: Mishra K.K. , Chaturvedi Ranu
Published: August 2008

Glutathione (GSH, RSH) and Methylene Blue (MB) interact in a mole ratio of 2:1 in acidic medium forming the corresponding disulfide and the leuco base. The reaction shows zero-order kinetics in MB and first-order kinetics in GSH, i.e. the rate is not affected on varying [MB]. The rate shows a fractional dependence on [H+] while there is no influence of variation of ionic strength on the rate of reaction. The rate constant increases linearly on increasing [Ru(III)]. The zero-order rate constant remains unaffected on varying the time of equilibration of the catalyst with the ingredients of the reaction system. The rate is not affected on addition of the disulfide, but addition of the leuco base slightly retards the rate. Activation parameters have been evaluated and a plausible reaction scheme has been proposed by presuming the interaction of transient Ru(II) with protonated MB as the rate limiting step. The kinetic results indicate that the glutamyl tripeptide moiety of GSH inhibits the reactivity of cysteine–SH towards MB in the presence of Ru(III).
Kinetic Rate Equations in Integrated form for Single-Step Reactions Involving Different Types of Reactant
Authors: Ray Anamika , Mandal Bholanath
Published: August 2008

A method has been developed to obtain kinetic rate equations in integrated form for reactions involving two or three different types of reactant with different stoichiometries. The integrated rate equation of a reaction of desired order has been shown to be generated in a stepwise manner with the help of the integrated rate law(s) of lower order(s) by this procedure. The beauty of this procedure is that it is devoid of complicated integrations. This method has a particular mathematical importance, in that it can be used to solve first-order differential equations that involve different terms, each of which is associated with some arbitrary power.
Real-Time Monitoring on the Kinetics of the Toluene Diisocyanate–Polyol Reaction
Authors: Qin Dawei , Meng Xia , Duan Hongdong , Li Xiaomeng , Du Dengxue , Yang Shouhuan
Published: August 2008

In-situ Fourier Transform infrared (FTIR) spectroscopy was employed to investigate the kinetics of the non-catalyzed polycondensation reaction between toluene-2,4-diisocyanate (TDI) and polyether diol. By monitoring the decrease in the NCO absorption band of TDI, the kinetic constants at different temperatures in the range from 50°C to 90°C were obtained and hence the activation energies. These studies showed that the reaction was divided into two phases, and a reasonable fit of the reaction profile could be obtained from combining the rate equations of each of the two phases.
Meo's Fists – Fighting For or Against Fascism? The Subversive Nature of Text and Image in Giovanni Bertinetti's I pugni di Meo
Authors: MYERS LINDSAY
Published: August 2008

During the 1920s and 1930s Italian children's literature was heavily influenced by fascist propaganda. Stories which celebrated patriotism, militarism and obedience appeared in great numbers as did biographies of Mussolini. Children's book illustrations also underwent stylistic changes becoming more statuary and geometric in accordance with the principles behind fascist architecture and propagandist art. Not all of the Italian writers and artists who ostensibly endorsed fascist ideologies, however, were entirely compliant with fascist dictates. Careful reading of some of the key works by writers and artists outwardly supportive of the regime reveals underlying subversive political ideologies, the majority of which have yet to be acknowledged. One of the ways in which writers and artists of the fascist period inscribed subversive ideologies in their works was by manipulating contemporary visual and verbal codes. This paper focuses on the dialectic of text and image in Giovanni Bertinetti's I pugni di Meo [Meo's fists], a children's fantasy, illustrated by the well-known artist, Attilio Mussino. Situating text and illustrations in their socio-political context, it discusses how these artists manipulated words and images to convey an ideology of moderation in the midst of excessive use and abuse of power in Italy in the 1930s.
Integrating Science and Human Values for Cancer Patient Care
Authors: Sutcliffe S. B.
Published: August 2008

The burden of cancer continues to increase globally, with substantial personal, societal, and economic consequences. Population growth and aging underlie this increase—a reflection of the effect of population health interventions in the last two centuries. Much of this gain has come through observation, derivation of evidence, and rigorous application of valid science to the public, both healthy and affected by diseases such as cancer. Increasingly, molecular medicine will affect the knowledge of cause and the personalization of therapy. However, science informs the decision-making process and places evidence within the beliefs of individuals and society as they relate to innovation, judgment, and values—the “logic” underlying alignment of conventional and complementary (holistic) care as a basis for compelling, consistent, and confident decisions.
Supporting Cancer Patients through the Continuum of Care: A View from the Age of Social Networks and Computer-Mediated Communication
Authors: Bender J. L. , O’Grady L. , Jadad A. R.
Published: August 2008

Almost since its inception, the Internet has been used by ordinary people to connect with peers and to exchange health-related information and support. With the rapid development of software applications deliberately designed to facilitate social interaction, a new era is dawning in which patients and their loved ones can collaboratively build knowledge related to coping with illness, while meeting their mutual supportive care needs in a timely way, regardless of location. In this article, we provide background information on the use of “one-to-one” (for example, e-mail), “one-to-many” (for example, e-mail lists), and “many-to-many” (for example, message boards and chat rooms, and more recently, applications associated with Web 2.0) computer-mediated communication to nurture health-related social networks and online supportive care. We also discuss research that has investigated the use of social networks by patients, highlight opportunities for health professionals in this area, and describe new advances that are fuelling this new era of collaboration in the management of cancer.
How Do We Evaluate Outcome in an Integrative Oncology Program?
Authors: Sagar S. M.
Published: August 2008

Integrative oncology focuses on the roles of complementary therapies to increase the effectiveness of conventional cancer treatment programs by improving defined outcomes such as symptom control, quality of life, rehabilitation, and prevention of recurrence. Implementation of integrative oncology programs should be based on the best evidence and must continually be evaluated to ensure quality, optimization of techniques, collection of new data, and cost-effectiveness. Useful domains that can be evaluated include symptom control, adherence to treatment protocols, quality of life, individual outcomes, prevention, rehabilitation, potential advantages of a whole-systems health approach, and economics of health services.