bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrical and Photographic Techniques for Measuring Microcracking in Some Fiber Reinforced Plastics
Authors: Mahieu William
Published: January 2012

In an effort to find new techniques for detecting and measuring the microcracking process in fiber reinforced plastic composites, detectable electrical effects and, in some cases, luminescence have been observed. The nature of these effects at present is not fully known. However, knowledge of their existence makes possible the use of electrical and photographic techniques for investigating microcracking in fiber/plastic composites. This paper describes several experimental techniques that have been utilized and presents quantitative results for several composite materials of current interest. Determination of the potential usefulness of these techniques will require additional knowledge of the nature of the effects and detailed correlation with the composite microcracking process. Further work should be directed toward these ends.
Microstrain in Continuously Reinforced Tungsten-Copper Composites
Authors: Hughes E. J. , Rutherford J. L.
Published: January 2012

The microstrain characteristics of continuously reinforced tungsten-copper composites have been studied as a function of volume fraction of fibers and prestrain. In the unstrained condition, the dislocation friction stress of all of the specimens studied had a value of approximately 0.28 kgf/mm2 (400 psi). The initial microyield stress, however, was dependent on the volume fraction of fibers, and a linear relationship was observed. Both the friction stress and microyield stress were prestrain dependent. The rate of increase of both of these quantities was dependent on the volume fraction of fibers. The results are discussed qualitatively in terms of high dislocation density regions in the copper matrix surrounding the fibers, which arise from stresses in the matrix as a result of the differential contraction between the tungsten and copper during fabrication.
The Role of Bond Strength in the Fracture of Advanced Filament Reinforced Composites
Authors: Gatti A. , Mullin J. V. , Berry J. M.
Published: January 2012

A great number of studies have been made to establish the longitudinal strength characteristics of composites, with success being measured in many instances by the degree to which “rule of mixtures” predictions have been attained. Several investigators report good agreement for modulus and tensile strength in metallic filament reinforced composites. Agreement for strength predictions is less frequent in systems using continuous and discontinuous nonmetallic filament arrays. This lack of ability to predict strength of uniaxially reinforced specimens points up the need for further research on the factors contributing to premature and sometimes catastrophic failure of filament reinforced specimens. As a result of using single and multiple filament specimens of boron in epoxy novolac, methods for localizing the damage resulting from individual filament fractures were developed. Optimization of the bonding mechanism is one area of research which has yielded some very interesting results. Contrary to the concept that bond strength should be as high as possible, these studies show that, although a good bond is essential to the reinforcing mechanism, too high a bond strength may render the composite severely matrix limited. Further, it has been demonstrated in this work that varying the nature of the bond surface can be most effective in isolating the sudden energy release at a filament fracture.
Effect of Platelet-Rich Plasma on the Outcome of Early Loaded Dental Implants: A 3-Year Follow-up Study
Authors: Ergun Gulfem , Egilmez Ferhan , Cekic-Nagas Isil , Karaca İnci Rana , Bozkaya Suleyman
Published: January 2012

This study evaluated the effect of local application of platelet-rich plasma (PRP) on the outcome of early loaded implants. Two implants were placed in the posterior region or bilaterally symmetric to the median line of the maxilla. Then, PRP was either applied or not applied to the implant sockets. Outcome measures were prosthesis and implant success as well as biological and prosthetic complications. Stability of individual implants was assessed manually and with a resonance frequency analysis device. The implant stability quotient (ISQ) was recorded on the operation day, on postoperative day 4, and at postoperative week 1. At the end of the first postoperative week, implants with ISQ values >60 were early loaded on day 7 with metal-ceramic crowns. Measurements were repeated at postoperative weeks 2, 3, and 4 and at postoperative months 6, 12, 24, and 36. One of the 64 implants was dropped out after 3 months of loading. No prosthesis failed. There were no prosthetic complications. Statistical analysis revealed significant differences between ISQ values of PRP and non-PRP implants on the operation day. Moreover, no statistically significant differences were found between ISQ values of PRP and non-PRP implants in the follow-up periods (P > .05). No appreciable clinical effect was observed when using PRP in the maxilla.
Comparison Between Immediate and Delayed Laser-Treated Implants Surface With Switching Platform: A Clinical Retrospective Study
Authors: de Moraes Eduardo José , Genovese Francesco Rao
Published: January 2012

The aim of the present study was to compare immediate (Im) versus delayed (De) placement of laser-treated implants surface with switching platform to confirm the predictability and performance of this type of implant. The implants were placed in pos exodontia and healed sites at the incisor, canine, premolar, and molar regions of the maxilla or the mandible. A protocol was prepared in which patient age, sex, implant length, diameter, and use of bone graft were recorded. The study included 44 GEASS Srl (Udine, Italy) implants with laser surface and morse taper connection, placed in 27 patients (mean age: 56 years; range: 25–80 years).The survival rates were 100% in the Im group and in the De group. The patients were followed for a minimum of 12 months. Implants with laser surface and morse connection presented when placed in fresh sockets showed similar results to implants placed in mature bone after 12 months of follow-up.
Added Value From High-end NMR Measurements to Reservoir Characterization: MREX deployment in GB field a Case Example
Authors: Udofia Abasiubong , Uguru Chukwuma
Published: January 2012

There was not a little apprehension within the GB Team when Baker_Hughes service reps informed the team that their nuclear magnetic resonance tool, the MRIL (Magnetic Resonance Image Log) was no longer available and was being replaced by their new tool, the Magnetic Resonance Explorer(MREX). Understandably, the discomfort lay in the fact that at the time the new tool was as yet untested in the African region and the subject well GU10 was a key well whose results would define the Nodal Development strategy for the nearly $2billion GB Integrated oil and Gas project. The uncertainties to be resolved by the GU10 well were the reservoir development, quality and character in the untested western flank of the field, the fluid type below the "Gas Down Tos" (GDTs) recorded for two key reservoirs, hydrocarbon-water contacts and the producibilityof the gas reservoirs. The classification of two key reservoirs either as non-associated gas (NAG) or associated gas (AG) was the critical uncertainty that impacted the most on development options. Though it shares the credit with an assortment of other tools, the MREX as promised, played a key role in reducing these uncertainties through providing lithology independent porosity and permeability as well as precise fluid typing that has been corroborated by samples taken from the same well. The results are shared in this paper and indicate that the target reservoirs, theD6 and the D8 have significant oil rims whose volumetric and economic significance must be assessed and possibly developed before the gas caps become available as feedstock for Nigeria’s LNG projects.
Case Study: Innovative Application Of Automated Drilling System With Hybrid Coiled Tubing Drilling Rig Excels In Cost-Sensitive Environment
Authors: Hadiputro Bimo , Corson Carl , Toner Troy , Doubek Lindsey , Fernandez Frank
Published: January 2012

Having explored many methods to improve efficiencies in conventional drilling processes, operators in the traditional North American land market are ever more attracted to innovative and cost effective means to drill wells. These innovative operators have turned to coiled tubing directional drilling (CTDD), with its promising inherent efficiencies in tripping and connection times, and with its smaller, logistically simpler footprint to optimize the drilling process even further. New downhole drilling technologies found in the conventional drilling arena are being applied to this operation to overcome the intrinsic limitations associated with the non-traditional slide-only drilling method associated with coiled tubing drilling. Together with innovative modifications to traditional CT rigs to address the fit-for-purpose needs of drilling, this novel approach to cost reduction is being applied in a cost-sensitive land market in the Rocky Mountain region of the US.

This paper provides an overview of the drilling application faced by the operator, of the specialized hybrid Coil Tubing drilling rig and of the novel application utilizing the modern, non-rotating rib-steering downhole drilling tools. The paper will benchmark the performance of the built-for-purpose operation compared to previous wells drilled with conventional rigs and directional motors, as well as other CTD systems. Additionally, a well to well performance of the drilling operation over a multi-well period will be evaluated, together with a discussion on lessons learned and a presentation of potential future improvements. The application of automated drilling systems with coiled tubing drilling heralds in a new age in developmental drilling in low spread cost markets.
Worldwide Pore Pressure Prediction: Case Studies and Methods
Authors: Tang Haixiong , Luo JunFeng , Qiu Kaibin , Chen Yingru , Tan Chee Phuat
Published: January 2012

The paper presents methods and multiple examples of published case studies of pore pressure prediction in worldwide deepwater exploration. The case studies show that seismic data were mostly used to carry out predrill pore pressure prediction, especially for wildcat frontier areas. It is critical to process seismic data to obtain more reliable fit-for-purpose velocity models and to apply appropriate pore pressure models. Real-time updating with newly acquired data allows the uncertainties of the predrill pore pressure prediction to be reduced ahead of the bit. This paper gives a brief introduction on worldwide deepwater exploration activities, provides a summary of the most common and frequently used pore pressure and fracture gradient methods, and captures best practices on pore pressure prediction for deepwater exploration.
Capturing Composition Variation in a 3,800-ft- Thick Gas Condensate Reservoir: How We Done It
Authors: Ryzhov Sergey , Tan Tina Lee , Ratanavanich Suvaluck , Tongpenyai Yothin
Published: January 2012

Conventionally, to define variation in fluid composition one needs to have results of a compositional laboratory study for each reservoir in the field or in a fault block of the field. The number of composition determinations, however, can be reduced if there is a clear depth or stratigraphic trend that allows interpolation of composition between available determinations. None of these, unfortunately, could be applied in the case of the studied field. This field is located in the Gulf of Thailand and is associated with a horst-graben pair of fault blocks that represent an alteration of some 50 sandstone reservoirs saturated with gas, gas condensate, and oil. The productive interval is subdivided into five main zones and the total thickness of all zones exceed 1000 m. In addition, the field is subdivided into two fault blocks that more or less double the number of individual hydrocarbon accumulations. Three pressurevolume-temperature (PVT) samples were taken in the field but full set of PVT experiments was performed for only one. For the other two, laboratory analysis was limited to the composition study.

With the limitations imposed by the data availability, an alternative approach to PVT characterization had to be introduced. It was based on the results of production data analysis and used a map of production condensate-gas ratio (CGR) prepared by production engineers to guide the composition variation in the field. Close cooperation between reservoir and production engineers from both the operator and service company was the key factor allowing successful implementation of this alternative.
Stick Slip Mitigation Plan to Improve Drilling
Authors: Zakuan Ahmad , Junaida Azreen , Subroto Bramanta , Hermawan Heru , Fatakh Abdul , Halim Abdul
Published: January 2012

Drilling performance becomes inefficient by the presence of vibrational effect which is stick and slip. This situation is a source of failure which reduce penetration rate, increase operating time, and contribute to increase drilling operating costs.This is due to the surface alternating between sticking to and sliding over each other, with a corresponding change in the force of friction. Only if kinetic friction is bigger enough to encounter this static friction, it can cause a sudden jump in the velocity of the movement, condition characterized by fluctuations in the rotational speed of BHA. The main objective is to come out with a solution in reducing stick and slip.First, the problem is encountered by means of the alignment of different drilling parameters, such as rotary speed, drilling torque and weight on bit. This conventional control technique required expertise from driller. Second, by introducing a roller reamer, the more effective control methodology. Roller cutters from the roller reamer rotate around the wall and it is able to provide low torque point of stabilization. It transforms the interaction between borehole and contact points by introducing a low-friction bearing between BHA and borehole wall.As a result, implementation of roller reamer shows the constant transmission of rotational energy, thus able to improve the weight to the bit. Two offset wells have been selected for this case study, with well #1 exercising conventional method while well #2 makes use of roller reamer. Stick slip effect reduces from 180% srpm to 30% srpm. Furthermore, it is able to save 40% of drilling time on that particular section. This paper focuses on the practical solution by implementing roller reamer to mitigate stick slip effect base on actual field scenario. A comparisons and conceptual models are provided as well as the illustration of its configuration.
Managed Pressure Drilling Enables Drilling Beyond the Conventional Limit on HP/HT Deepwater Well
Authors: Arnone M.. , Toralde J.. , Carr D..
Published: January 2012

This paper describes some successful applications of Managed Pressure Drilling on exploration wells drilled in deep waters. Building upon successful experience utilizing MPD from HPHT jack-up wells, the Operators transferred the experience across to deepwater exploration projects.

Extensive engineering, training and development of procedures were carried out prior to spud for each project. Specific techniques were developed to handle floating drilling operations. The resulting benefits associated with MPD led to improvements in drilling performance, and eliminated many of the traditional problems faced on other HPHT wells in the area. MPD has now become an integral part of the well operating philosophy and has established new standards for drilling wells of this type in the area.

Some critical wells were classified as wildcats with considerable pore pressure unknowns, coupled with narrow pore-fracture drilling window characteristic of HPHT conditions. MPD was able to minimize the problems faced on the wells by enabling various techniques to be utilized. These techniques included the use of pressure build up analysis to quantify formation pressures, the application of dynamic flow checks, dynamic formation strength limits, and the application of constant bottom hole pressure during dynamic and static drilling fluid circulation conditions. The planning, development and execution phases of the MPD projects are detailed in this technical paper.
Extending the Life of Mature Field by Light Workover Cementing Technique
Authors: Hadiaman Farid , Neto Nilo Bianchi
Published: January 2012

Handil field is a giant mature oil field in Indonesia. It’s been producing since 1975, being the current recovery factor for oil 49% and 57% for gas. Cumulatively, the total oil produced is around 855 MMstb and gas around 1.68 Tcf. Today, oil is being produced at 20,000 bopd, gas at 75 mmscfd and water at 130,000 bwpd.

Enhanced oil recovery projects, infill wells and light workover of existing wells are key elements to maintain field production. This paper describes an innovative light workover intervention, called Annular Squeeze Cement that helps keeping Handil field production performance at its best level.

It covers the field study analysis that led to this the technique, some precautions and current challenges concerning the cementing operation as part of light workover activity. It also share lessons learnt from the field execution and evaluation. A case study is also presented for a full understanding how this cementing placement technique contributes to the field performance.

This technique was successfully implemented and acts also as one of the important element to extend the life of a giant mature field where economic and success ratio becoming a paramount parameter.
Successful Approach of Scale Cleaning Using Organic Dissolvers To Delay Scale Re-Deposition at Pariwali Well # 5: A Case Study
Authors: Rana Muhammad Arif , Ahmed Riaz-ud-din , Dar Afnan A
Published: January 2012

Production drop caused by down hole scale deposition is becoming a serious problem not only in wells producing with high water cut but also in deep, hot, sour gas wells with very low water cuts(trace to 6%).

This paper presents a case study of CaCO3 & CaSO4 scale deposition in a sour well in north of Pakistan that resulted in substantial production drop. HCl (15%) was used to dissolve/wash the scale obstruction in the tubular and clean the perforation of well. Although the treatment was successful in dissolving the scale and restoring the production, yet these production gains were lost rapidly. Scale dissolver treatments followed by scale inhibitions were also implemented but no appreciable results were achieved. A detailed in house study was carried out by POL for scale analysis and its removal techniques. Scale monitoring by produced water analysis, gauge cutter runs, production & WHFP fluctuations, gas analysis and review of seven scale cleaning jobs guided to carry out organic scale dissolving job.

It was concluded that 15% HCl acid pumped to dissolve the scale precipitate out due to increase in PH and Bi Carbonate decomposition caused by CO2 evolution. Scale removal with organic dissolvers (Acetic acid) proved successful because it maintained low PH which prevented re-precipitation of acid products. With this approach scale re-deposition was delayed ranging from nine days to nine months.
Experimental and Numerical Investigation of Steam Flooding in Heterogeneous Porous Media Containing Heavy Oil
Authors: Ashrafi Mohammad , Souraki Yaser , Tor Joergen Veraas , Karimaie Hassan , Torsaeter Ole
Published: January 2012

Thermal recovery methods and especially steam flooding have long been considered as the most effective methods to unlock heavy oil reservoirs. These highly viscous hydrocarbon deposits are proven to constitute a huge proportion of total world oil reserves. Large volumes of heavy oil are located in heterogeneous porous media containing high permeable wormholes or non-permeable shale barriers. High permeable zones can be the results of sand migration in loose and unconsolidated sandstones. There is a question of how these non-homogeneities can possibly enhance or hinder the flow of high viscous oil, steam and condensed water under a steam injection process.

This paper addresses experimental and simulation study of steam flooding in heterogeneous porous media that contains Athabasca heavy oil. Some PVT properties of Athabasca crude oil have been measured experimentally and simulation study was accomplished using a numerical thermal reservoir simulator. A horizontal layer of high porosity and permeability was assumed in the middle of a core to verify the performance of steam injection in a 20 cm long sandstone core with a permeability of 640 mD saturated with Athabasca heavy crude. High permeable zone had a permeability of 5 D. Different shale barrier configurations were also considered to examine the effect of these no flow layers. Considering a heterogeneous system, sensitivity analyses were focused on the effect of injection rate, porosity, permeability contrast and thickness of high permeable zone. Different steam temperature and quality cases for core flooding experiment in this system were also investigated.

The most important conclusion is that there is an optimum steam temperature and quality for most efficient steam injection. It was figured out that shale barriers in the model can hinder the flow of oil and cause high residual oil, but their impact is dependent on permeability distribution in the core.

The permeability contrast between the high and low permeable layers should be smaller considering both oil production and steam oil ratio (SOR), which is a measure of economy. Although core permeability of 640 mD provides satisfactory recovery and SOR, higher permeability can cause faster recovery and lower SOR, since the injection can stop earlier. Porosity of the model is found to have an inverse relation with the oil recovery and SOR. Results also clearly show that higher injection rates improve the oil recovery. However, SOR should also be considered at the same time. There is a trade-off between recovery and SOR. It is also clear that lower thickness for the high permeable zone results in better recovery while causing high injection pressure at the inlet. This corresponds with lower permeability contrast case.
Improving ESP LifeTime Performance Evaluation by Deploying an ESP Tracking and Inventory Management System
Authors: Bougherara N. E. , Ahmed K. Si , Algdamsi H. A.
Published: January 2012

One of the most popular and efficient artificial lift mechanisms is the electrical submersible pump (ESP). According to recent statistics, there are more than 100,000 ESPs worldwide. With the increasing number of wells equipped with ESPs, operators are making substantial efforts to improve ESP performance and achieve longer runlife. The primary focus has been on tracking ESPs sensors real-time data, along with failures prediction as proactive measures. It is however, still difficult to keep track of historical ESP pull and run jobs, ESP equipments, and benchmark pump runlife. Typically there are no structured datastores for ESP movements. ESP runlife statistics are stored in multiple individual spreadsheets and are resource-intensive to compile.

This paper presents a solution that enables to track within database software ESP operations, equipments movements and failures along with classical production data to enable better ESP lifetime evaluation and equipments management. The solution encompassed ESP operations and equipment tracking within a next-generation production volumes management system. The software and database were expanded to ensure that data was generated through a single point of reference, so that operators could capture and store downhole and surface equipments tracked via serial-number along with operations details and failures. ESP runlife, failure and equipment statistics were also calculated and reported graphically. More accurate ESP lifetime was calculated using well production uptime, installation and pull dates. Using these key statistics, the asset team was able to benchmark equipments and vendors. Each time the team needed to design or redesign an ESP, the solution enabled them to browse current and historical production, ESP operations, and both installed and warehoused equipments data. Used equipments historical installations can be tracked to make informed decisions before any reinstallation in other wells. In addition, the solution allows through reports to track wells with longer pull operations time providing input to improve rig workover planning. In summary, the proper capture, validation, data browsing, and accurate performance evaluation enabled by the pilot solution reduced routine work time, positively impacting the asset team. More time could thus be dedicated to recurrent problems identification, in-depth investigations for remedial actions for underperforming ESP wells.
A Current Mapping and Predicting of Indonesian Flow Assurance Challenges Based on Fluid Physical Characteristics
Authors: Nengkoda Ardian , Supranto Supranto , Sulistyo Hary , Prasetyo Imam , Amijaya Hendra
Published: January 2012

A domain of "flow assurance" is a key concern in the oil and gas industry, and refers to the need to guarantee the flow of oil or gas from reservoirs to processing facilities in the face of a number of engineering challenges, especially in offshore environment. The Indonesian next future exploration and production predicting to be more to deep water offshore, remote production, floating gas production-supply and will face more difficult fluid impurities to be dealt with such increasing volume of produced water, inorganic/ organic scale, mercury and H2S/ CO2. As preliminary, a comprehensive quick review of production and operational problems across the regions both onshore and offshore and PVT fluid data base have been done. These early information on fluid physical characteristics and chemistry can be beneficial to see the potential of tight emulsion, hydrate problems, inorganic scale precipitation or asphaltene/ wax deposition. It is important for flow assurance perspective, to gather all lesson learnt across the offshore production, where these information can be useful for the next future oil and gas exploration and production strategy. As one case, for example, in one of the offshore field in East Kalimantan and Madura East Java, the emulsions were unusual tight where oil-water are difficult to separate and creating a process up set and in the end, creating such lost of production. However, if we look detail across regional geological basin, the emulsion tendency from formation fluids of offshore Kalimantan ever been identified. Furthermore, in the deepwater environment especially, the produced fluids tend to cool significantly, thereby losing the benefit of heat-induced demulsification and causing waxes to precipitate start from downhole, sub sea, trough the surface facilities. The initial base line study have been performed to pick early flow assurance problems base on quick fluid physical characteristic and chemistry from early stage exploration sampling (DST or MDT/PVT). It involves an "integration work flow" of understanding better the physical fluid characteristics from the reservoir and its journey from pore to process facility and it relations to production flow assurance problems. Other important production chemistry and flow assurance issues from Indonesia oil and gas offshore production that being addressed include: gas hydrate, inorganic scale, emulsion, H2S/ CO2 corrosion, reservoir souring (due to waterflood), asphaltene and wax deposition and mercury corrosion. Finally, as a finding, basic reservoir fluid information can be link to the future production problems and flow assurance study has an important role in maximizing the production and minimizing the facility bottle necking.
A New Method to Forecast Reservoir Performance during Immiscible and Miscible Gas-Flooding via Transfer Functions Approach
Authors: Sayyafzadeh Mohammad , Mamghaderi Azadeh , Pourafshari Peyman , Haghighi Manouchehr
Published: January 2012

In order to improve oil recovery during gas flooding, it is crucial to afford an accurate estimation of future performance. So far, different approaches have been developed to present forecasting. The most common reservoir simulator, grid-based, which has the highest accuracy, suffers from some weaknesses; time-consuming computation and also need for large quantity of data. Sometimes, a quick overview of reservoir performance is adequate or all required data are not accessible. Therefore, in this study a fast simulator is introduced to provide a quick overview with the minimum amount of data.

In this study, the development of a method based on transfer functions (TF) is presented to model immiscible and miscible gas flooding. TF is a mathematical representation in Laplace domain which demonstrates the relation between the input and output signals of a system. In the proposed method, reservoirs are modeled with a combination of TFs. The order and arrangement of the TFs are chosen based on the physical conditions of the reservoir which are ascertained by checking several cases. Injection and production mass rates act as input and output signals respectively. TF parameters are calculated using history matching. Also, a fractional flow model is introduced and coupled with the TF system to obtain oil production rate as the final output.

In an attempt to validate the approach, it is required to compare the results with the grid-based method. Six different synthetic cases are constructed and used to validate the developed approach. The results state a good agreement with those obtained from the numerical simulators.

This approach is a quick way to predict gas flooding performance with minimum amount of data, production and injection rates data are the only requirements. It can be a new window for the future of fast simulators. It provides estimations with plausible certainty. On the other hand, the analytical solution of method enables its utilization in finding optimum rates for gas injection in a short period of time. The method also presents some key parameters such as well connectivity. It is fair to state that the use of the model is limited to situations when a rapid estimation is looked for and/or adequate data is not accessible.
Fully Automated Fluid Level Measurement Tool
Authors: Sam G. , Kaestenbauer M. , Burgstaller C. , Chevelcha E.
Published: January 2012

The fully automated fluid level measurement tool was developed recently. The paper describes the technical features of the tool and shows via case study the results of the field tests on various Electrical Submersible Pumps - ESPs and sucker rod pumps – SRP, running with and without Variable Speed Drive - VSD.

The unique feature of this system is its fully automated and purely electronic functioning. The measuring device is enclosed, mounted on the casing valve, has a pressure rating of 350 bar (5000psi) and works with zero emissions on the environment (no outlet of casing gas).

Compared with a conventional downhole pressure sensor, mounted on an ESP, the system is insensitive to high well fluid temperatures and simple to maintain due to its easy access on surface location. It additionally has a sampling rate of down to one measurement per minute. The measured fluid level data can be transmitted via SCADA system.

The measurement tool enables to run a pump in a more safe way. It can be used to avoid pump off conditions and the resulting equipment damage. It can also be used to control a VSD to keep the fluid level in a well at a specific depth to avoid bottomhole flow conditions below the bubble point pressure. Due to the availability of online fluid level data, all kind of pumps (e.g. ESP, Sucker Rod, PCP, Jet Pump) can be operated safely at more aggressive production rates in order to mobilize more oil.

Furthermore the vision and corresponding thoughts of acoustic well diagnosis, also a feature of the tool which is currently under investigation, are presented.
Failure Analysis and Consequent Process Improvements for a Down-Hole Intervention Tool
Authors: Fisher Jerry , Haq Mohammed A. , Bansal R. K. , Bailey Thomas F.
Published: January 2012

This paper describes development and testing of a new guide shoe mill (GSM) for intervention fishing services in conjunction with the well construction’s drilling hazard mitigation. Primary application of this mill is for milling guide-shoe left in the well by the solid expandable running tool system. The traditional milling direction is downwards. The new mill was designed to mill upwards in the reverse direction, thereby clearing the restriction and restoring the well bore casing drift internal diameter (ID). This paper covers development of guide shoe mill, failure analysis on a test well, and improvements done in various steps to prevent future failures. Use of Finite Element Analysis (FEA) models and extensive lab tests are also discussed.

The ability to maintain stabilization while milling in a high vibration environment and to remove cuttings to the surface were two major challenges. The guide shoe mill out tool provides stability, efficient well cleaning to restore casing drift ID, thus saving on non-productive time (NPT) and other drilling related costs. The study of failure prevention has lead to better technology applications and process improvements. Successful results obtained from lab testing (including test rig) lead to potential application in other areas such as selective section casing patch removal.
University Accreditation Requirements Could Create Positive Opportunities for Increasing Professional SPE Membership
Authors: Lau Richard Arthur , Lau Laura , Alhasani Nadia Mehdi , Williams John M.
Published: January 2012

Abstract While recent economic events have restricted opportunities for technical professionals in some geographic areas of the petroleum industry, it has boosted opportunities in others. This shift has forced many petroleum engineers to look outside their traditional marketplaces for new or continued employment or advancement opportunities and has increased the need for verification of university credentials of foreign applicants In Europe and North America, engineers rely on non-governmental, outside agencies, like the USA based Accreditation Board for Engineering and Technology Inc. (ABET), to prove their engineering programs have met established quality standards by achieving accreditation. For engineering programs in emerging markets, like the United Arab Emirates (UAE), there had been no need for accreditation beyond national organizations. However, with the accelerating global demand for professional graduates to be able to certify their credentials, several private and public universities in the UAE have just completed or are in the process of accrediting their programs. Demanding transparency and consistency, accreditation is a rigorous process whose standards force universities to refocus their output and strive for continuous improvement. One standard addressing lifelong learning opportunities, for example, requires that a program meet not only the needs of its current students but also the needs of its alumni, a group largely ignored in the past.
Generalization of Dual-Porosity System Representation for Hydraulic Fracturing–Stimulated Shale Reservoir (Part 2): Modeling, Simulation Workflow, and History Matching Studies
Authors: Du C. Mike , Li James
Published: January 2012

Recently, a new methodology has been developed to model hydraulic fracturing induced fracture network and simulate a shale reservoir as a dual porosity system. The reservoir geological and petrophysical data are integrated to build both structure and property models. Microseismic (MS) data are used to delineate stimulated reservoir volumes; event intensities are employed to estimate hydraulic fracture intensity. The fracture intensity is calibrated by using hydraulic fracturing job data and geomechanical properties through the fracture propagation mechanism.

As part one of this title in previous study, a theoretical framework generalization for the new methodology was introduced. Modeling and calibration of fracture network by stage, by well, and by well pad are discussed. A superpositioning technique is used to process the overlapping of MS mapping responses from different stages. Different fracture network geometry and average fracture width are evaluated. Various stimulated volume expansion models are investigated for proppant placement estimations and fracture conductivity distributions. A procedure is also introduced to build a simulation model when MS data is lacking by utilizing treatment data, geomechanical parameters, and user experience on estimated stimulation volume configurations. In this paper, that framework generalization is updated with new analysis. We focus on details for implementation of the methodology, modeling workflow, and stepwise procedure. The process is comprehensive, giving full consideration to shale reservoir integrated modeling, data input, fracture network geometry configuration, intensity calibration, and calculation of dual-porosity model parameters for reservoir simulation and other fracture network properties.

This extended methodology and workflow can be applied to single well and multiple-well modeling when the well drainage volumes are interconnected. It provides an effective means for modeling and simulation study as well as history-matching calibration of stimulated shale gas reservoirs. The new modeling methodology was applied to a Barnett shale field case, and sensitivity and history matching analyses were carried out.
Utilizing Gross Heating Value Management in Field Development Planning
Authors: Wiboonkij-Arphakul C. , Tsai Ing Jye , Jablonowski C.
Published: January 2012

This paper discusses the challenges of integrating into an existing gas field a marginal field with poor gas quality that would otherwise be left stranded.

To prepare for the poor quality gas, this study added gross heating value (GHV) to the traditional scheduling analysis to ensure that the quality of sales gas blended from various fields would always meet specifications. The addition of GHV to the traditional scheduling analysis required devising a GHV forecasting method, creating a GHV management procedure, and implementing a new revenue allocation method. Each of these innovations required specific tasks. Examples of these tasks and their challenges are presented in this paper.
Coiled Tubing and Jointed Tubing Hybrid-String Well Intervention: Design, Testing, and Case History
Authors: Ehtesham Asif , Howard Robert , Lindsay Sharlene
Published: January 2012

The decreasing frequency and size of new oilfield-reserve discoveries and an increased demand for energy is forcing industry professionals to find more creative methods of extracting every drop of oil possible. Pinpoint stimulation is one of the processes that enables service companies to target smaller plays with treatments customized to their specific characteristics.

Throughout the ongoing evolution of this process, improvements are constantly being made to enhance the treatments. One of the latest improvements is the introduction of a coiled tubing (CT)/jointed tubing (JT) hybrid unit that combines the advantages of CT’s continuous movement with the rigidity of JT. For extended-reach horizontal sections, the hybrid-string hydraulic workover (HWO) jack supplies the horsepower to push it to bottom while the depth-reaching capability of the JT greatly exceeds that of the CT, which can buckle and lock up before reaching total depth (TD).

The equipment consists of an HWO rig-assist unit, reel trailer with powerpack, HWO tower with tubing guide, CT (top), JT (bottom), and a bottomhole assembly (BHA). The BHA includes a new-style safety valve that protects the flapper from erosion during sand pumping and can be surface or remotely activated for positive well-pressure control.

The advantages of running this configuration include the capability to run larger-sized CT for higher flow rates and faster treatments of longer horizontals, as well as the capability to continuously forward or reverse circulate.

In addition, the hybrid allows the JT to be hydraulically disconnected at the BHA after treating, thus leaving it in the hole as a completion or velocity string. This new technology is proving to be a new game-changer in well intervention.
The Use of Combined Static and Dynamic Material-Balance Methods in Gas Reservoirs
Authors: Ismadi D. , Kabir C. S. , Hasan A. R.
Published: January 2012

Estimating in-place volume associated with each well, leading to estimation of total reservoir in-place volume, is the cornerstone to any reservoir-management practice. Yet conventional methods do not always lend themselves for routine applications, particularly when used in singular fashion. However, combining them on the same plot has considerable merit in that they converge to the same solution when material-balance-derived average-reservoir pressure is used.

This study presents a systematic procedure for estimating the initial gas in-place volume (GIIP) when real-time surveillance data of pressure, rate, and temperature are available at the wellhead. Specifically, we show that log-log diagnosis, followed by combined static- and dynamic-material-balance analysis, and transient-productivity-index (transient-PI) analysis lead to consistent solutions. Thermodynamic behavior of fluids is also explored to ensure that the converted pressures at the bottomhole and measured rates have consistency and accuracy for reservoir-engineering calculations.

Layered systems were selected for this study because they represent most situations. Two synthetic cases probed issues pertaining to average-reservoir pressure computation with the pseudosteady-state (PSS) approach, and two field examples validated the approach presented here.
Dual Eccentric Reamer BHA Solves Hole Opening Challenges and Conductor Sharing Pass through Constraints
Authors: Raziyev Mukhamed , Liang Qingjian Jim , Syaifullah Nalom , Lee Swee Lyn , Willis Simon , Tang Kien Hoe
Published: January 2012

PETRONAS Carigali and Schlumberger IPM have formed an alliance to develop a field in offshore Malaysia. Due to space limitations, a platform extension was installed to accommodate three additional conductor sharing wellheads (CSW). Project challenges include limited CSW pass-through, well collision risk, highly unconsolidated formations in the angle building section, directional control and shallow gas zones.

To avoid well-to-well collision caused by poor directional control, a pilot hole must be drilled under the conductor to provide good directional control in the unconsolidated sandstone. The pilot hole must also mitigate shallow gas risk. To achieve the reservoir hole size and accommodate dual gravel-pack completions, the pilot hole must be opened from 8–1/2" × 16" to allow subsequent hole section drilling.

The project team had to design a BHA that could efficiently deliver the objectives with minimal rig time. To solve the challenges a new hole opening methodology would be required. The pre-drill analysis included studies in: BHA durability/dynamic stability to ensure good hole quality; hydraulics and fluid dynamics to deliver proper cooling and hole cleaning; optimized combination of hole opening technologies. To reduce reaming runs/bit trips, a dynamic modeling system was employed to quantitatively analyze the interaction of various downhole tools and optimize the BHA configuration/drilling parameters.

The modeled dual eccentric PDC hole-opening BHA was run and successfully solved the challenges, mitigated risks and met the required drilling objectives for completing the six CSW wells. A post-drill simulation analysis was performed to analyze the dynamic downhole BHA behavior with the actual operating parameters.

The authors will explain how the BHA was developed and successfully used in the field to solve the unconsolidated formation challenge. Survey method and challenges of drilling through the conductor sharing wellhead are also discussed.
Challenges in Improving the Hydrocarbon Gas Recovery: Case Study Using a Carbonate Gas Condensate Field in Malaysia
Authors: Jalil Mohd Azran , Masoudi Rahim , Darman Nasir H. , Sofia Nor Zarith , Othman Mohamad
Published: January 2012

Initiatives on improved hydrocarbon gas recovery are usually facing challenges which are directly related to representative understanding of reservoir and fluid flow characterization as well as the depletion strategies. A field case study has been used as a platform to explain such challenges and the adopted integrated methodologies toward improving the hydrocarbon recovery from the field. Reliable water saturation modeling, validation of the production allocation, reevaluation of the trapped/residual gas saturation (Sgr), modeling of regional aquifer behavior and its support, connectivity and pressure communication among the fields, fluid contact movement, gas expantion, smeared oil rim and condensate drop-out within the reservoir and appropriate production scenarios (i.e., off take rate, strategy, etc.) are among the challenges.

This paper presents on methodologies how to manage the challenges in improving the hydrocarbon gas recovery (i.e., IGR) through an integrated subsurface-surface study for the evaluation of giving a gas reservoir second life i.e. field rejuvenation. The adopted methodology integrates both simple analytical approaches including the the material balance and volumetric assessment as well as the 3D simulation modeling to evaluate the reservoir performance and examine some of these uncertainties and challenges and subsequently identify the value of the field second life through the optimum prediction and production strategies. As the studied field is in pressure communication with neighboring fields in a mega platform carbonate build-up through a stronge regional aquifer, the results from an isolated model for the field showed to be unrealistic and, therefore, an integrated mega platform model is constructed for the purpose of the study.

The study integrates the 4D seismic results, regional aquifer and trapped gas saturation modeling, reservoir performance monitoring, and its application to obtain a better history matching results and reliable prediction strategy for recovery factor improvement. By incorporating the 4D seismic results and representative water saturation and residual gas saturation modelling, the resulting history matched model is significantly improved with less degree of uncertainty and it is believed to be more reliable to produce optimum prediction scenarios, which focused on recovery factor enhancement. Various prediction scenarios together with advanced modeling of the regional aquifer effect in a merged mega platform model have been examined using the final history matched model. By doing this, the field recovery factor is improved by 16% and thus giving the field the second live to continue its production.
Reservoir Characterization for Fracture Distribution Prediction and New Well Target Identification
Authors: Lefranc Marie , Farag Sherif , Li Bingjian
Published: January 2012

One of the main challenges in the fractured basement exploration and development is the identification of proper well targets with minimized drilling risk. The estimation of fracture porosity and permeability distribution in reservoirs with low matrix porosity is also very challenging as the production relies mostly on the complex fracture network. The proposed method aims at identifying the potential flow-contributing fractures, modeling accurately the fracture density in the interwell space, and finally, building a robust and well-calibrated discrete fracture network (DFN) that is used to compute porosity and permeability properties. This holistic approach integrates the latest technologies for interpreting borehole images, identifying open fractures, computing fracture aperture, and generating a DFN. It also includes at each step qualitative and quantitative analyses to optimize the choice of 3D parameters: seismic attributes and estimations of fracture length, orientation and aperture distribution.