bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of 3D Laser Imaging for Inspection of Coiled Tubing
Authors: Christian Amitkumar , Tipton Steven M. , Emnett Amanda R. 
Published: April 2008

Abstract
Current coiled tubing (CT) inspection technology is based predominantly on magnetic flux leakage (MFL). This approach is useful for detecting flaws on both the outer and inner surface of tubing. However, MFL is currently incapable of consistently providing information about the geometry of the flaw, which is adequate to assess its influence on fatigue endurance.
The use of 3D laser imaging has demonstrated the potential to detect flaws, but more importantly, to completely characterize their geometry. With the full three-dimensional mapping of the defect surface, critical defect parameters can be computed. For example, the system provides immediate information about the depth, length, width and projected surface area with a high degree of accuracy. Additionally, other features can be extracted from the laser images, including the volume of the defect and the notch root radius, which could be used to refine quantitative estimates of the flaw's severity.
Promising results from prototype systems are presented. A CT specific tool is being developed to scan known defects, detected visually or with existing inspection technology, and compute their influence on remaining fatigue life. This could serve as the basis for the development of stand-alone laser-based CT inspection systems. Additionally, a system has been developed that is capable of passing through coiled tubing in order to characterize flaws on its inner surface.
Expanding the Use of Turbodrills in Coiled Tubing and Workover Applications
Authors: Grigor Charlie , Conroy Dave , Henderson Marc 
Published: April 2008

Abstract
With the ever increasing demands placed on downhole tools with well reaching deeper depths, increasing bottomhole temperatures, and reduced bottomhole pressures these hostile environments place increasing demands on the tool providers to supply tools that will withstand these ever increasing demands. One way to overcome these demands is to utilize a purely metallic drilling tool such as a downhole Turbodrill. The turbine power section and bearing section are constructureed with only metallic components eliminating the requirement for elastrometic stators, which have proven problematic, when bottomhole temperatures reach or exceed the rated temperatures or nitrogen is required to ensure well integrity.
Traditionally turbodrills have been utilized for the most extreme high pressure and/or high temperature, hard rock-drilling applications – this paper will expand on some of the latest improvements to the tool design such as blade design which has enabled the tool length to be reduced allowing easier rig up for coiled tubing applications. Testing of the tools as well as case histories are included, that will illustrate that the Turbodrills can be used as successfully in challenging drilling and work-over applications.
Improved System for Accessing Multilateral Wells in Canada
Authors: Harber B. , Stuker J. , Pipchuk D. 
Published: April 2008

Abstract
In the past, the operational and cost concerns of being able to treat and evaluate multilateral wells have left operators with limited economical options for remediation and evaluation. This paper describes a combination of fiber optic-enabled measurement system and a selective multilateral reentry tool.
The new system’s bottomhole assembly design includes a multilateral reentry tool and real-time bottom hole feedback. The live feedback provides the operator with constant tool position in the wellbore which can serve as a key indicator of downhole tool function. With these specific measurements, downhole CT operations can be tracked and analyzed more quickly and clearly than ever before. Furthermore, this constant stream of critical data arms the onsite engineers and operators with information to make immediate decisions and thereby increase overall intervention efficiencies.
This paper demonstrates how this system has been effectively used during stimulation services for openhole multi lateral wells in Canada.
Fiber Sweeps for Hole Cleaning
Authors: Ahmed R. M. , Takach N. E. 
Published: April 2008

Abstract
Cuttings transport in highly deviated wellbores is more challenging and critical than in vertical wells. In inclined wells, the fluid velocity has a reduced vertical component that may not be sufficient to transport all the cuttings to the surface. When cuttings returns do not appear to be sufficient for the drilling rate, hole cleaning sweeps are applied to clean the borehole or reduce cuttings bed thickness. Fiber-containing sweeps have been very effective in cleaning highly deviated and extended reach wells. In addition, substantial torque and drag reduction has been reported when fiber-containing drilling fluids are used in the field. Although field observations are encouraging, currently very little is known about flow behavior, hydraulics and cuttings transport efficiency of fiber sweeps.
There is a great need for understanding how fiber particles enhance the cleaning capabilities of fiber-containing sweeps. The interaction between fiber particles and drilling fluid is still not fully understood, although the improvement in cuttings and solids transport is attributed to the formation of a fiber mat/network that enhances the carrying capacity of drilling fluids.
This article presents results of experimental investigations conducted to study hole-cleaning performance of a fiber sweep. Flow loop experiments have been carried out to evaluate and compare sweep efficiencies of the fiber sweep (0.47% Xanthan Gum and 0.04% synthetic fiber) and the base fluid (0.47% Xanthan Gum). Equilibrium bed heights were measured at different sweep flow rates in horizontal and inclined configurations. Results from this study indicate that a fiber-containing sweep has better hole cleaning capabilities than the base fluid, even though these two sweep fluids have very similar rheological properties. Moreover, adding fiber slightly reduces friction pressure loss under turbulent flow conditions.
Intervening With Coiled Tubing Through the Tubing-Casing Annulus to Restore Well Control
Authors: Sonnier Baine , Sackash Mark 
Published: April 2008

Abstract
It is common for coiled tubing (CT) to be sent to rigs to circulate kill-weight fluid when a rig has lost well control. This is a safe, effective means of regaining the well-control barrier so that normal rig operations can resume. Occasionally the rig is not able to simply shut in at surface while coiled tubing is being delivered, leading to closing of the rig's blind shears. In such cases, coiled tubing intervention is less common.
This paper discusses a situation that developed off the coast of Louisiana in which primary well control was lost, forcing the rig being used in a workover operation to close its blind shears on a dual-tubing string. The resulting situation left 4,175 psi pressure at surface and 9-lb/gal fluid in the well. Coiled tubing was then run into the tubing-casing annulus to 9,250 ft and 16.5-lb/gal fluid was circulated down the coiled tubing and out the casing. This paper discusses the prejob modeling, operation, and outcome of this work.
Entering Multilateral Wells Using Coiled Tubing
Authors: Proctor Robert , Grant Ryan , Marron Andrew , Cubas Danny 
Published: April 2008

Abstract
Coiled tubing is utilized to enter horizontal wells for the purpose of performing general remedial well operations. Common operations performed include but are not limited to stimulation treatments, solvent treatments, cleanouts and water shut-off. In today's oilfield, many horizontal well plans incorporate the drilling of multiple laterals. Entering multiple laterals, in one well, using coiled tubing, requires guidance. Advanced completion designs may facilitate such guidance. However, in the case of open hole multi-lateral wells a guidance system is not incorporated in the completion design. This paper will discuss a reliable commercially available technology, developed for the purpose of entering open hole multilateral wells using coiled tubing. The paper will review bottom hole assembly functionality, development of this technology and applications. In addition, offshore case histories of wells entered using multi-lateral entry guidance technology will be summarized.
Efficient Offshore Scale Removal Without a Rig: Planning, Logistics, and Execution
Authors: Guimarães Zacarias , Almeida Victor , Duque Luis H. , Pinto Julio C. , Coutinho Sandro , Chagas José V. , Costa Giovani V. , França Alessandro B. , Gouveia Manoel , Peixoto Cristóvão , Teles Carlos A. 
Published: April 2008

Abstract
Although the oil industry seeks to increase the worldwide production of hydrocarbons, various well and reservoir problems can severely reduce oil and gas production from individual wells, leading to the requirement for intervention. For example, in mature fields offshore Brazil, production platforms with minimal open work space and without workover rigs have been a challenge for restoring production in wells with serious scaling problems. The scale build-up reduces production, month by month, until a rig has to be mobilized to replace the production string.
Trying to recover production efficiently, service and operating companies have been presenting solutions that circumvent the practical limitations of these locations.
In the last three years, an operator's engineering department has worked with service company engineers to develop the means to rig up a 1-3/4-in., 4500-m-long coiled tubing string in a work area of 234 sq. meters and with a crane with a 12-ton maximum capacity. This cooperation allowed intervention in wells on rigless platforms, reducing working time, environmental impacts and costs.
These interventions helped to increase oil production from Field A in the Campos Basin and gas production from Field B in the Santos Basin, currently the most important gas field offshore Brazil.
Both fields suffer from severe scale deposition -- barium sulfate in Field A and calcium carbonate in field B -- which builds up in the production string and effectively reduces the internal diameter, consequently reducing production.
The new successful interventions in these fields using rigless coiled tubing and scale removal techniques enhanced the hydrocarbon production from these fields.
In Field A (oil production), interventions were performed in seven (7) wells, providing around a 40% increase in production.
In Field B (gas production), interventions were performed in five (5) wells, providing a production increase of around 27% per day.
This paper details the planning, logistics and techniques used to successfully meet both challenges. The same solutions would apply in other fields around the world where platform space and scarcity of rigs limit an operator's ability to remediate scale or other wellbore problems that constrain hydrocarbon production.
New Electro-mechanical Perforating Technology Reduces Cost and Increases Safety in Workover Operations
Authors: Bargawi Riyadh A. , Dean Doyle , Clemens Jack , Whitmire Clem 
Published: April 2008

Abstract
Saudi Arabia wells, onshore and offshore, often require workovers as a result of the corrosive environment to which the downhole equipment is subjected. When the workover jobs required a single hole to be punched in "soft" tubing using traditional methods, high failure rates and inherent delays in mobilizing explosives often severely compromised job economics.
This paper presents several case histories in which a new slickline-deployed electro-mechanical tubing punch was used for the first time worldwide. Although the workover requirements in each well were different, and the jobs were conducted in both onshore and offshore environments, all required a single hole to be drilled.
The case histories will discuss the advantages provided to the operator through use of the new electro-mechanical tubing punch. These included: 100% perforating reliabilityReduced rig time by eliminating mobilization of explosives and other equipment, if failures occurred.Reduced costs, since electro-mechanical perforating is more cost effective than electric-line "soft-shot" methodsApplicability to deployment on slickline, E-line, or coiled tubingSimplicity in use of the electro-mechanical perforatorEnhanced personnel and environmental safety from: Elimination of explosivesUse of alkaline or lithium batteriesUse of mono-conductor lineUse of CTU pressure-switch adapter
The new method was 100% successful and resolved the problems experienced with all previously used conventional mechanical perforating methods. Although run in highly corrosive downhole conditions, the perforating tool had 100% success in perforating the "soft" tubing. A thorough follow-up inspection of the tool showed that it had sustained no damage of any kind.
An in-depth discussion concerning the electro-mechanical perforator design, its application in Saudi Aramco wells, its operational advantages, and its significant impact on safety and economics will be presented.
Field Experience Using an Intervention Wellhead Structure Modeling and Monitoring System
Authors: Newman Ken , Smalley Ed , Linares Lionel , Kelleher Patrick 
Published: April 2008

Abstract
A case history of an attempted CT intervention in 43' of water through a wellhead leaning at a 45 degree angle is presented. A major concern for this intervention was the integrity of the intervention stack between the leaning wellhead and the CT injector located on a lift boat. The stack design, testing and stack performance during the job execution are presented.
Deepwater Isolation Valve Contingencies Using E-Line Stroking Tool
Authors: Schwanitz B. 
Published: April 2008

Abstract
Many subsea completions employ a down hole isolation valve for temporarily closing off production while awaiting first oil or flow line connections. These valves are designed to be opened or closed through surface pressure pulses in the fluid column to activate stored nitrogen in the valve housing. When a valve fails to activate as expected, a reliable contingency plan must be ready or the financial consequences can be large.
With the use of electric wireline tractor technology, a contingency valve opening system allows malfunctioning isolation valves to be mechanically shifted with depth precision and controlled force. This method uses an electrically powered hydraulic stroking tool to shift the valve sleeve open or closed with a selected force of 10K - 30K lbs depending on the type of valve. The stroking tool is either tractor conveyed in high angles or run with only a shifting tool attached in low angles. A new intelligent key tool replaces the spring loaded shifter, to allow the system to be run "slick" and avoid hang ups on down hole profiles that can occur with the conventional spring loaded shifting tools.
An electric line deployed solution is faster to mobilize, more precise in locating shifting sleeves and less expensive than alternative solutions. A review of case histories will prove these points. Also, pre-job planning, integrated team involvement, SIT and operational recommendations will be discussed.
HP/HT WCCL Technology Aids Successful Deployment Perforating Operations on the Glenelg Field
Authors: Gordon William , Pittman Iain , Rydlewicz Mervyn , Innes Richard 
Published: April 2008

Abstract
This paper describes the results obtained as well as the equipment and techniques used on the Glenelg field in the UK central North Sea (CNS) to perforate and complete a new high-pressure high-temperature (HPHT) production well.
This paper begins by discussing the types of equipment required for HPHT coiled-tubing (CT) intervention. This includes the front-end engineering for the hottest, deepest, highest pressure, and most deviated well produced from, to date, in the UK CNS. This paper discusses the CT string design, as well as the selection of downhole tools, for temperatures above 400°F. The CT intervention, wireless casing collar locator (WCCL), depth correlation, and perforating operations are presented. This is the hottest environment in which WCCL technology has been successfully applied worldwide.
The lessons learned during this project, together with the results from this case history, are presented. Conclusions are drawn about moving forward with both the WCCL technology and conducting similar operations.
Cleanouts With Coiled Tubing in Low-Bottom-Hole Pressure Wellbores
Authors: Li J. , Luft H. B. , Wilde G. , Alingig G. , Jumawid F. 
Published: April 2008

Abstract
Cleaning debris from a wellbore is a common operation with coiled tubing (CT). Considering that this process is a complex function of fluid properties, flow velocities, hole size, deviation angle and particle properties, it becomes particularly challenging in wells with low bottom hole pressures (BHP).
There are two circulation modes involved in conventional sand cleanouts with CT, namely forward and reverse circulation. Either sand cleanout method may apply excess hydrostatic pressure on the formation that can result in loss of circulation and returns, hence making cost effective solids removal impossible as well as potentially damaging the formation. In conventional cleanouts, nitrogen or low density hydrocarbon fluids can be used to reduce hydrostatic pressure; however this necessitates a very careful job design and execution which can require expensive volumes of nitrogen (N2) or hydrocarbon fluids. An alternative technology that combines a concentric coiled tubing (CCT) string with a down hole jet pump to remove solids from a wellbore but without placing any additional hydrostatic pressure on the formation has also proven to be remarkably successful.
This paper reviews these different solids cleanout methodologies and summarizes the advantages and limitations related to each method when used in low formation pressure wellbores. New solids transport flow loop test results, related to a hydrocarbon fluid, are summarized and compared with tests using water. Case histories are presented that demonstrate how to select the most appropriate cleaning method based on well conditions.
Successful Offshore Application of Acid Tunneling Technology: Overcoming the Difficulties of High Depths, Temperatures, and Deviations
Authors: Alonso Perex Luis Angel , Diaz Jose Daniel , Navarro Manuel , Moss Paul , Curtis James 
Published: April 2008

Abstract
Field applications of acid tunneling technology began in late 2005 in the Mara Field of Western Venezuela as an alternative to both initial new well stimulation and producing well maintenance. In this field, acid tunneling is used to treat sections of formation in an open hole completion that have been severely damaged from invasion of muds, cements and/or fluid loss control material in an attempt to interconnect the microfractures present in dual porosity carbonate formations. Since the initial trial, thirteen wells have been successfully treated with this technique; obtaining long term production increases. The large majority of wells situated in the Mara Field exhibit the same two primary conditions: shallow average depths around 6000 ft and temperatures around 200 °F. A logical step in the development process of this technique would be to successfully apply the process in areas outside of Venezuela and with more stringent wellbore conditions.
This paper outlines the operational procedures and subsequent results from the successful implementation of the acid tunneling process in an offshore, open hole completed well located on the Casablanca Platform in the Mediterranean Sea, offshore Spain. A hydraulic kick-off tool and a specially designed jetting assembly were deployed on coiled tubing to create a single lateral hole in a carbonate reservoir using hydrochloric acid as the treatment fluid. This was the first implementation of the acid tunneling process outside of Venezuelan borders. It was also the first application in a well with a depth greater than 7,000ft and a bottomhole temperature greater than 200 °F. Finally, it marked the first time the process was used on an offshore well. The well characteristics, the operational procedures, and the improvements made to the acid tunneling tools for this project are discussed.
Wireline Deployed Metal Sealing Bridge Plug System: Operational Learning Curve and Subsequent Redevelopment
Authors: Chapman I. C. , Ng K. S. , Nor N. M. , Mackenzie G. R. J. , Garfield G. L. 
Published: April 2008

Abstract
This paper will focus on a project to redevelop a wireline deployable metal-to-metal seal, ISO 14310 VO qualified, retrievable bridge plug system to allow it to be conveyed successfully in a high rate gas well for acid stimulation zonal isolation operations. Functionality of the original system including the plug and hydrostatic setting assembly had previously been tested in a fluid environment yet envisioned for a gas well application. Initial well installations gave results that led to a reconsideration of the forces being generated by the running and pulling tools due to the differences between a gas and a fluid environment and their impact on system reliability and functionality. The paper will discuss some of the problems discovered with the system for this particular application and the system redesign over a one-year period, which included a number of qualification tests performed at near to real well conditions. This discussion will include information on the complexities of performing such tests and the solutions used to develop a successfully qualified "fit-for-purpose" redesign. The paper will conclude with a high-level overview of the system's first deployment in an actual field well application.
Evaluation of induction characteristics and hypnotic potency of isoflurane and sevoflurane in healthy dogs
Authors: Hofmeister Erik H. , Brainard Benjamin M. , Sams Lisa M. , Allman David A. , Cruse Ashley M. 
Published: April 2008

Abstract
Objective—To determine induction characteristics and the minimum alveolar concentration (MAC) at which consciousness returned (MACawake) in dogs anesthetized with isoflurane or sevoflurane.
Animals—20 sexually intact male Beagles.
Procedures—In experiment 1, 20 dogs were randomly assigned to have anesthesia induced and maintained with isoflurane or sevoflurane. The MAC at which each dog awoke in response to auditory stimulation (MACawake-noise) was determined by decreasing the end-tidal concentration by 0.1 volume (vol %) every 15 minutes and delivering a standard audible stimulus at each concentration until the dog awoke. In experiment 2, 12 dogs received the same anesthetic agent they were administered in experiment 1. After duplicate MAC determination, the end-tidal concentration was continually decreased by 10% every 15 minutes until the dog awoke from anesthesia (MACawake).
Results—Mean induction time was significantly greater for isoflurane-anesthetized dogs (212 seconds), compared with the sevoflurane-anesthetized dogs (154 seconds). Mean ± SD MACawake-noise was 1.1 ± 0.1 vol % for isoflurane and 2.0 ± 0.2 vol % for sevoflurane. Mean MAC was 1.3 ± 0.2 vol % for isoflurane and 2.1 ± 0.6 vol % for sevoflurane, and mean MACawake was 1.0 ± 0.1 vol % for isoflurane and 1.3 ± 0.3 vol % for sevoflurane.
Conclusions and Clinical Relevance—Sevoflurane resulted in a more rapid induction than did isoflurane. The MACawake for dogs was higher than values reported for both agents in humans. Care should be taken to ensure that dogs are at an appropriate anesthetic depth to prevent consciousness, particularly when single-agent inhalant anesthesia is used.