bluuebunny/crossref_metadata_2025_split huggingface dataset:
Overcoming the Weak Link in Cemented Hydraulic Isolation
Authors: Moroni N. , Panciera N. , Zanchi A. , Johnson C. R. , LeRoy-Delage S. , Bulte-Loyer H. , Cantini S. , Belleggia E. , Illuminati R. 
Published: December 2007

Abstract
Preventing unwanted migration of hydrocarbons has been an enduring challenge to the oil and gas industry. Regulations are in place to minimize the risk of leaking wells. However, future regulations are expected to become increasingly restrictive requiring operators to minimize the risks of potentially unwanted hydrocarbon migration during the well planning stage.
Hydrocarbon flows may originate from pay zones, or from non-commercial hydrocarbon-bearing formations. Some of the most hazardous gas flows have originated from unrecognized gas behind conductor, surface or intermediate casing. Often determining the precise source of annular flow is difficult.
There are numerous short-term solutions aimed at preventing the flow of hydrocarbons including optimizing stand-off, fluid placement, slurry design and mechanical methods. These techniques relate to working with the cement slurry in its liquid state prior to curing, and are aimed at preventing undesirable movement of hydrocarbons within the cemented annulus before the cement has set. However their effectiveness is lost once the cement has set, making it vulnerable to hydrocarbon migration should cement sheath damage occur.
The paper describes a unique isolation solution based on a responsive cement system with intrinsic self-healing properties automatically activated upon hydrocarbon exposure. Activation occurs whenever the integrity of the cement sheath is compromised, e.g. cracks and microannulus, and then efficiently seals the leak path by a swelling mechanism. The solution rapidly forms a complete hydraulic barrier by healing damage, and continues to re-seal should further damage occur. The technical advantages of this solution are shown, illustrated through successful field tests.
Crosswell Electromagnetic Tomography in Haradh Field: Modeling to Measurements
Authors: Marsala Alberto F. , AlRuwaili Saleh , Ma S. Mark , Modiu Sanni L. , Ali Zaki , Donadille Jean-Marc , Wilt Michael 
Published: December 2007

Abstract
Crosswell electromagnetic (X-well EM) resistivity is emerging as an intriguing technology for reservoir surveillance. It provides a cross-sectional resistivity image between two wells and has the potential to provide fluid distribution at an inter-well scale. It can be used for identifying bypassed hydrocarbons, monitoring macroscopic sweep efficiency, planning infill drilling, and improving effectiveness of reservoir simulation. It can be deployed for one-time or time-lapse surveys.
A crosswell EM technology trial project is being conducted in an Upper Jurassic carbonate reservoir, at the Ghawar Field in Saudi Arabia, to monitor the movement of injected water flood front and map the fluid distribution. The project site is in Ghawar's southern region, Haradh Field, and consists of three wells in the oil-water contact zone where peripheral injection water may have produced an uneven flood-front distribution.
Significant drilling and well deepening were required prior to the deployment of tools in the three-well triangle. In fact, one new well was drilled and two other wells were deepened by more than 200 m, so that good volumetric coverage could be obtained at the oil- water contact zone. Extensive logs, core and formation tests were also acquired to provide deterministic saturation profiles at the near wellbore region. Formation evaluation in the project area indicates that one of the wells was fully swept while a second well, some 400 m away, was not.
In July 2007, crosswell EM surveys were acquired across the three Haradh wells. In spite of the large well separations, the acquired EM data had good quality, and good stations repeatability. Preliminary processing has revealed a structure consistent with the background structure but a clear image of the oil-water contact is yet to be made.
Laboratory Experimental Results of Huff ‘n’ Puff CO2 Flooding in a Fractured Core System
Authors: Asghari K. , Torabi F. 
Published: December 2007

Abstract
In this study, the performance and efficiency of CO2 huff-and-puff process for improving oil recovery and subsequent storage of CO2 in fractured porous media is examined and the results of laboratory tests are presented. The experimental set up consisted of a high-pressure stainless steel cell made specially to hold a cylindrical core with spacing around it to simulate fractures surrounding matrix. The matrix was saturated with normal decane, which was used as oil during these experiments. Over six sets of huff-and-puff experiments, using CO2 as solvent, were conducted for pressures of 250, 500, 750, 1000, 1250, and 1500 psi. Each set of the huff-and-puff experiments were conducted by injecting CO2 in the fracture surrounding the core (injection step). Then, the system was shut-in for a period of 24 hours to allow CO2 to diffuse from fracture into the oil in matrix (soaking period step). At the end of soaking period, the pressure was released and the oil production was measured (production step). The above cycle was repeated until no more oil was produced. The results obtained showed that CO2 huff-and-puff process improves the oil production from fractured media, significantly. These results also indicate that the oil recovery is higher for huff-and-puff experiments conducted at higher pressures.
Infinite-Acting Physically Representative Networks for Capillarity-Controlled Displacements
Authors: Behseresht Javad , Bryant Steven L. , Sepehrnoori Kamy 
Published: December 2007

Abstract
Drainage/imbibition simulations are traditionally performed on finite regular lattices. If physically representative networks are used instead, the spatial correlation of pore space features inherent in granular materials is automatically accounted for. However, even these networks are obtained from finite samples, and conditions must be specified on the boundaries. Making the conditions correspond to physically realistic situations is difficult, especially for simulations of phase trapping. This paper presents a method of constructing infinite-acting model rocks, in which a well-defined criterion for phase trapping is possible that is independent of boundary conditions. The foundation of the model is computer generated dense random periodic packings of spheres. We illustrate the method with simulations of drainage and irreducible wetting phase saturations. To eliminate possible confounding effects from grains being arranged differently, we compare simulations in infinite-acting networks with simulations in the finite network taken from the unit cell of the periodic packing.
Wetting phase connectivity is assessed globally and accounts for all phase morphologies, including pendular rings. This enables a physically rigorous method of identifying clusters of trapped pores: A "wrap-around" cluster of wetting phase is effectively infinite, and drainage of one or more pores in the cluster is deemed possible. All other clusters of wetting phase cannot undergo further drainage. Qualitatively different behavior is observed than when local connectivity criteria are used for trapping.
The nonwetting phase percolation threshold and the drainage endpoint are not sensitive to the choice of inlet pores in infinite-acting networks. For a finite network the percolation threshold was similarly insensitive, but the drainage endpoint was highly sensitive to the number and location of the exit pores. Comparison with experiments showed that a strict criterion of wetting phase connectivity (pores connected only by throats filled with wetting phase) cannot account for typical values of Sw,irr and that connectivity must persist via pendular rings.
Typical laboratory experiments and simulations in finite networks yield drainage curves that approach irreducible wetting phase saturation Sw,irr gradually, with large changes in capillary pressure inducing only small changes in saturation. Simulations in infinite-acting networks do not exhibit this behavior. We argue that these simulations are more representative of behavior in the field, and that typical laboratory measurements underestimate the value of Sw,irr.
Unique Micronized Weight Material Delivers Ultra-Thin NAF to Optimize ERD Drilling
Authors: Matlock Wayne , Conn Lee 
Published: December 2007

Abstract
A newly introduced dry micronized weight material (MWM) designed to improve hydraulic pressure management while mitigating sag tendencies for drilling challenging extended-reach wells has been used successfully in recent Gulf of Mexico drilling projects.
The application of the MWM while drilling narrow hydraulic windows, typically observed in deepwater wells, has led to new breakthroughs in the ability to model and manage the physio-chemical interactions of extremely small weighting agents with the chemicals and base fluids that constitute non-aqueous fluid (NAF) systems. From these advances, it is now possible to design and utilize weighted fluids that are ultra-thin, and possess significantly lower viscosity than fluids using traditional weighting materials.
Observations from both laboratory and field tests indicate a very stable NAF can be maintained with much lower equivalent circulation densities (ECD), reduced surge/swab pressures, and lower surface pressure requirements. Another observation using MWM is reduced friction. These factors have allowed users of the MWM to improve drilling performance by increasing flowrates for borehole cleaning while reducing excessive pressure spikes resulting from elevated viscosity and cuttings accumulation. Although the viscosity characteristic of MWM formulated fluids are very low, barite sag or settling potential is minimized or eliminated. The ultra-thin rheological values are designed to deliver improved drilling performance by establishing an optimized operating window determined from hydraulic modeling.
This paper will discuss the background development work on this new MWM, and provide details from the first field trial in which the new fluid system was used on a critical extended reach deepwater project. Additional field performance data from subsequent field trials will also be presented, where the improved hydraulic pressure management benefits from the new MWM is clearly demonstrated.
Understanding Post-Expansion Properties of Solid Expandable Tubulars
Authors: Butterfield Chuck , Flaming Sarah , Lebedz Rodger , Thigpen Michael , Hill Rick 
Published: December 2007

Abstract
As an enabling technology, solid expandable tubulars continue to revolutionize the design and construction of oil and gas wells. Although solid expandable systems are now widely accepted as a viable casing alternative, some operators do not apply the technology in their wells. Limited information regarding the tubulars' post-expansion performance properties creates uncertainty in the application of solid expandable tubulars. A better understanding of how the pipe properties are affected by the expansion process is imperative to optimizing the benefits of system application.
Using American Petroleum Institute (API) performance equations on post-expanded tubulars do not clearly identify the limits of the pipe. Testing is underway to create accurate predictive models for expansion force and post-expansion collapse. These full-scale laboratory tests, using API methods where applicable, determine how the expansion process changes collapse resistance and residual stress. Pre and post expansion mechanical and material properties are analyzed using American Society for Testing and Materials (ASTM) methods. Testing for H2S and CO2 environments employ the NACE methods.
This paper describes the testing procedures and results of the post-expansion performance property testing. These findings will be compared and contrasted to API standards for conventional pipe. In addition, the paper will discuss industry implications for determining solid expandable tubular standards.
What Software Do We Expect? An Engineering View vs. IT View
Authors: Wang Sharon , Woo George , Chen Zhongming 
Published: December 2007

Abstract
In today's modern computing era, computer applications have become indispensable for engineers to do their work. Some software works well, meeting technical requirements and expectations, while others are not very effective because of their instability, unfriendly user interface, or difficulty to use. Since computing is a typical skill of engineers and the engineers also know the solutions for the particular problems, it is common for them to write programs for their own needs. However, as a project and application grow bigger and more sophisticated, the problems related to application software design and architecture, which impact software extensibility without degrading the software performance, become apparent. When a program is written without concern for overall design, the maintenance of the software becomes more costly and difficult. Alternatively, a program developed by an individual who lacks the necessary technical background, may not be intuitive to use or may not address all technical needs of the engineer. A good program not only must meet the business requirements and specifications necessary to provide engineering solutions, but also must be user-friendly, and intuitive for users to learn and use easily. Thus, the users can focus on their specific job instead of struggling with a confusing manual, or trying to avoid causing a software crash. Understanding the business domain and prospective user's practice helps developers create more useful tools.
This paper discusses the cause of the problems in software quality from the perspective of both the user and IT professional on complexity and facilitation, extensibility and adaptability of software. The paper also proposes some suggestions for IT professionals to develop quality, favorable application software for users. It also provides guidelines for engineer users and project managers to evaluate and purchase software.
Using Ultrasonic Techniques to Accurately Examine Seal Surface Contact Stress in Premium Connections
Authors: Hamilton Kirk , Wagg Brian , Roth Tim 
Published: December 2007

Abstract
One of the most important functions of a tubular connection is sealability. This is especially the case for premium connections which are commonly used in the demanding conditions of HPHT and Thermal Well applications. Sealability therefore also is one of the most important criteria used during connection qualification in which the capability of the connection is verified for the characteristics of the application. During qualification tests it has been found that breakdown in connection sealability can be traced to damage on the primary seal surface, which can eventually develop into a leak-path.
Ultrasonic inspection technology can be used to provide a means to obtain non-intrusive measurements of contact stress between two mating metal surfaces separated by a thin lubricating film. While the technology has a wide scope of potential applications in this respect, the technology has been specifically developed to measure seal surface contact stresses inside oilfield tubular premium connections.
This application of ultrasonic technology has been used numerous times during connection qualification programs to assess the quality of the contact stress band in premium connections. During these analyses the technology has been able to detect scratches, galling, pock-marks, and other types of seal surface damage in a wide array of premium connection designs. Most of these flaws cannot be detected on the torqueturn curves generated during connection makeup. Moreover, mechanical separation of mating premium connection seal surfaces under tensile and compressive loads has been observed using this technology.
This paper will cover the basic concepts of premium connection design, as well as some of the issues that can affect the sealability of premium connections. As well, this paper will include an overview of the use of ultrasonic technology as a technique to assess the contact stress along the metal-to-metal seal band of a premium connection, and methods used to monitor changes in the contact stress profile induced by many installation and service loads.
Extreme Temperature ESP Development
Authors: Tetzlaff Steve , Wonitoy Kelvin , Ward Brad , Burleigh Lawrence , Dodds Adrian 
Published: December 2007

Abstract
Efforts to develop electrical submersible pumping (ESP) system technology for harsh environment applications has resulted in equipment designed and developed specifically for applications in higher temperature wells. This paper will discuss the development evolution of this equipment through Centrilift's state-of-the-art high temperature test facility "hot loop" and continuing development by field operations in Canadian SAGD applications.

Internal Development
The utilization of a state-of-the-art test facility that can be entered and exited at strictly planned / controlled intervals where temperature, system cycling and system monitoring can be controlled in a safe environment, has been instrumental in advancing the ESP equipment technology to a satisfactory operational level at 200° C – 220° C (392° F – 428° F) environments. This facility allows the equipment component design and materials evaluation to proceed quickly and under controlled procedures, with the end result being a fully tested and evaluated system for field applications. Several equipment modifications based on the test results will be discussed.

Field Testing/Development
The utilization of customer owned producing wellsites for initial application of the extreme temperature equipment is critical for the final ‘live’ well test of the design and tweaking of minor issues that would be difficult to detect under cleaner and controlled lab type environments. Further equipment design focus beyond 250°C will be dependent upon SAGD operators' targets and requirements.
Case Study: Drillstring Failure Analysis and New Deep-Well Guidelines Lead to Success
Authors: Bert David R. , Storaune Anders , Zheng Nanjiu 
Published: December 2007

Abstract
Three drillstring fatigue failures occurred while drilling two deep wells below 16,500 ft true-vertical depth (TVD) in the U.S.A. midcontinent region. All the failures occurred across 2°/100 ft to 3°/100 ft dogleg severity intervals from 6,000 ft to 8,000 ft. The well conditions (i.e., pipe condition and directional plan) were not significantly different from other deep wells in the area, which had not failed.
A deep-well drillstring failure study was conducted which included a review of drillstring inspection reports, daily drilling reports, digital data, technical literature, and engineering analysis for the two wells.
A Cumulative Fatigue Analysis (CFA) modeling technique taking into account specific well conditions (i.e., wellbore geometry, rotary speed, rate of penetration, hook load, and drillstring configuration) was applied. The model indicated that drillstring failures would occur across shallow doglegs mainly because of high hang-down loads combined with slow rate of penetration (ROP). The results of the study led to the development of new deep-well design criteria and implementation of new drilling guidelines. The new guidelines included utilization of look-ahead CFA modeling when approaching drillstring endurance limits to minimize drillpipe fatigue failures.
Look-ahead CFA modeling and the new drilling guidelines were used on two subsequent deep wells in the area, leading to successful drilling to total depth (TD) of 18,000 ft TVD without failure. One of the wells had a 1.4°/100 ft dogleg severity (calculated based on 100 ft survey spacing) at 1,500 ft and drillpipe shuffling was required to prevent drillstring failure in the deep hole section. The drillstring fatigue failure prevention guidelines apply to deep wells drilled worldwide.
Acoustic Determination of Pump Intake Pressure in Wells Producing Low-API-Gravity Crude
Authors: McCoy J. N. , Rowlan O. L. , Podio A. L. , Brunings Carlos A. , Riviere Armando 
Published: December 2007

Abstract
The acoustic determination of the pump intake pressure in wells producing viscous low API gravity crude is presented in this paper. These wells have liquid above the pump and the pump is set above the formation and gas flowing upward through the gaseous liquid column. The method to determine the pump intake pressure involves the acoustic measurement of the liquid level and the casing-pressure buildup rate when the casing head valve is closed. When these data are used with this paper's new empirically derived correlation for viscous crudes, then an accurate gradient of the gaseous liquid column in the annulus is obtained. This new correlation provides a more accurate correction of the gaseous gradient of the fluid above the pump intake for wells producing viscous crudes.
Results are presented from field testing of numerous wells where the actual gradients of gaseous liquid columns were measured is wells having a variety of gas flow rates and an oil gravity in the range of 10 degrees API. A back pressure valve is used to increase and stabilize the casing head pressure and the valve is used to depress and to stabilize the liquid level at different depths while the well is produced at a constant rate. Over a period of many days the acoustic measurements to the stabilized liquid levels are acquired. The gradient of the gaseous liquid column is then calculated and the pressures are extrapolated to the pump intake depth. Development of a new correlation from the analysis of this field data improves the accuracy of pump intake pressure determination in wells producing viscous low API gravity crude.
Modeling the Mechanical and Phase-Change Stability of Wellbores Drilled in Gas Hydrates by the Joint Industry Participation Program (JIPP) Gas Hydrates Project, Phase II
Authors: Birchwood R. A. , Noeth S. , Tjengdrawira M. A. , Kisra S. M. , Elisabeth F. L. , Sayers C. M. , Singh R. , Hooyman P. J. , Plumb R. A. , Jones E. , Bloys J. B. 
Published: December 2007

Abstract
In April 2005, the Chevron Joint Industry Participation Project (JIP) on Gas Hydrates organized a drilling and coring expedition to potential gas hydrate sites in Atwater Valley and Keathley Canyon in the Gulf of Mexico. In support of these activities, methods were developed to predict the mechanical and phase change stability of boreholes drilled in sediments containing gas hydrates.
Models of mechanical failure and downhole temperature were constructed from seismic and log data for the wells in Atwater Valley and Keathley Canyon. Model results were compared with LWD caliper, image, and temperature logs in three boreholes. LWD logs were also used to assess drilling performance.
Mechanical failure models compared favorably with deformation features observed in image logs in all three wells. An excellent match was also obtained between the modeled and measured downhole temperatures in Atwater Valley. However, for reasons that remain unknown, temperatures observed in the Keathley Canyon wellbore were generally lower than those predicted by the model.
Time-lapse analysis of LWD data revealed that the equivalent circulating density (ECD) in Atwater Valley became abnormally high and coarse-grained solids were falling into the BHA annulus from uphole causing packoffs. These packoffs eventually caused the rotary to stall. Some evidence that the packoffs were caused by shallow water flows discharging large quantities of sand into the wellbore was found.
Post-drill temperature simulations indicated that the LWD boreholes in Atwater Valley and Keathley Canyon were sufficiently cool to prevent hydrate from dissociating, owing in part to successful management of circulation rates in the borehole. It was also shown that loop currents at Atwater Valley helped to reduce the risk of dissociation.