bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Numerical and Analytical Approach for Determining Formation Fluid-Sample Clean-up Behavior through Multiple Sensor Analysis
Authors: Eyuboglu S. , Proett M. , Gao L. , Sliman W. , Senne R. , Pedigo B. , Engelman B. 
Published: April 2012

Abstract
The accurate determination of fluid properties and contamination while sampling with a wireline pump-out formation tester is essential to achieve the primary objective of obtaining representative reservoir fluid samples with minimum rig time. Despite advancements in fluid identification sensors, sampling in mixed phases, especially immiscible fluids, still poses a great challenge. It often happens that apparent erratic sensor responses are attributed to sensor noise, but careful study reveals that the sensors are actually showing the true nature of the multi-phase fluid flow. However, if this multi-phase behavior is not considered, it can be difficult to determine fluid type and contamination. This work addresses the development of a new numerical and analytical investigation that makes it possible to not only understand the cleaning behavior of formation fluids but also quantitatively determine fluid qualities in real time. This newly developed technique highlights the variables that play an important role in guiding the clean-up process and, at the same time, provides the temporal characteristics of the contamination level versus both time and fluid volume. Furthermore, uncertainties in the pumping time required to achieve the desired level of contamination are also calculated with this method. Field examples from Gulf of Mexico, South America and North Sea are provided to demonstrate the efficiency of this technique in oil-based mud and water-based mud contamination examples for both hydrocarbon fluid and formation water samples, with comparisons to PVT laboratory measurements. An error analysis is performed for each example, and results are presented in this research.
The new analysis technique is applied to a high-resolution fluid density sensor that monitors the change of resonance frequency of a vibrating tube-carrying fluid sample. The same interpretation method is also applied to a capacitance sensor and a resistivity sensor to further confirm the results derived from the density sensor.
Enhancing the Effectiveness of Workover Interventions with Coiled Tubing and Real-Time Downhole Measurements
Authors: Franco Ernesto , Molero Nestor , Gerardo Miguel , Nevarez Cesar , Martinez Arturo , Marin Eric , Pérez José 
Published: April 2012

Abstract
In offshore Mexico, operators have increased workover activity to maintain oil and gas production. The reservoir is a naturally fractured carbonate with gas and water flowing through the natural fractures, leaving oil trapped in the matrix. Controlling gas and water production is critical to prevent unwanted fluid from reaching the wellbore.
Currently the combined progression of gas and water contacts has reduced the oil window from several hundred to as little as 40 m in some wells. In these conditions, and with rapidly advancing gas and water contacts, it is paramount to provide solutions to restrain unwanted fluid from reaching the wellbore.
One of the most common workover interventions consists of isolating the water producing zone with coiled tubing deployed through-tubing inflatable-packers (CTD-TTIP) and perforating an upper oil-bearing zone. The problem is compounded by low reservoir pressure, resulting in heavy losses while drilling and cementing production zones; loss of zonal isolation as result of cement sheet failure through the producing intervals; and wells completed with a combination of large tubular sizes.
Recently, operators and service companies in offshore Mexico have implemented an innovative workflow intended to enhance the effectiveness of water control interventions in this challenging work environment, through the utilization of realtime downhole measurements (RTDM) via coiled tubing equipped with optical fibers (CT-EOF) for accurate control of CT depth, the packer inflation process, packer differential pressure limits during the treatment injection, and fluid placement.
This paper provides a technical analysis of the engineering process required to develop successful workover zonal isolation jobs with CTD-TTIP and RTDM in offshore Mexico, and presents a case history, lessons learned, conclusions, and recommendations from the experiences gained while performing CTD-TTIP with RTDM in offshore Mexico.
Calculation of Gearbox Torques of Rotaflex Pumping Units Considering the Elasticity of the Load Belt
Authors: Takacs G. , Chokshi R. 
Published: April 2012

Abstract
One of the most successful long-stroke pumping units available today is the Rotaflex, a completely mechanical device. Its construction is entirely different from the traditional beam pump mechanisms and has polished rod stroke lengths up to 366 in. Due to the low pumping speeds required and the special geometrical arrangement Rotaflex units require significantly less torque than beam pumping units and provide several other advantages over those.
The unit's most important component is a uni-directionally rotating roller chain connected to the polished rod through an elastic load belt. The kinematic behavior of the chain, running on two sprockets is relatively simple to describe; the paper presents exact formulae for the calculation of polished rod position, velocity, acceleration, and torque factor functions. The recommended formulae provide a theoretically sound description of the unit's kinematic behavior and can serve a sound basis for the calculation of gearbox torques for cases when load belt stretch is neglected.
Prior publications on Rotaflex operations relied on the assumption of a rigid load belt and determined the loading of the gearbox accordingly; field practice, however, indicates considerable stretch in the elastic belt. The paper, for the first time, presents a thorough investigation of the kinematic performance of Rotaflex pumping units with due consideration of belt stretch. The effect of operational stretch due to polished rod load on gearbox torques and the energy conditions of Rotaflex units is investigated through several example problems.
Workflow Automation (WFA) for the Integrated Production Operations in the Macuspana Field
Authors: Villanueva C. Cruz , Tapia C. , Calatayud A. , Benumea M. , García A. , Hernandez V. H. , Balcazar J. A. , Lotar T. , Purwar S. , Rodríguez J. 
Published: April 2012

Abstract
Workflow automation (WFA) is a key element for integrated production operations in oil and gas assets. Identification, analysis, optimization, and automation of workflows enable a integrated and cross-disciplinary vision of the asset and in consequence, enable a more timely and accurate decision making process.
This paper describes the production management workflow optimization and automation for the Pemex Macuspana asset, which is an onshore asset located in Tabasco, Mexico. This paper describes how an adequate integration between processes, people, and technology enables operational goals to be reached within a short period of time.
The Macuspana asset has more than 100 production wells and a complex surface network, which is interconnected with other Pemex production assets. To optimize and automate the production management workflows of this asset, a complete workflow automation solution was implemented, which includes a common web environment enabling data capture, validation, and visualization. It also includes a workflow orchestration engine for integration with engineering applications, optimization, and automation of production operations processes. As part of the implementation, the following activities were completed: Automatic calculation of production volumes on a daily basis using well and network modelsWell test validation workflow incorporating well model update and operational constraintsForward simulation and back allocation engines to automatically distribute production volumes
After deployment, the solution enabled teams across various disciplines to collaborate and to analyze production estimates and asset performance more accurately, minimizing production losses. The solution delivered is the first important step of the Macuspana asset toward the implementation of its digital oilfield (DOF) initiative.
GaStim Concept - A Novel Technique for Well Stimulation. Part I: Understanding the Physics
Authors: Restrepo A. , Ocampo A. , Lopera S. , Diaz M. , Clavijo J. , Marin J. 
Published: April 2012

Abstract
Well stimulation for production or injection enhancement in mature fields is a key and challenging task. Loss of reservoir energy due to pressure depletion coupled with complex damage scenarios existing in adverse petro physical environments can become restrictive factors for the proper performance of conventional liquid based chemical stimulation systems. Main limitations are normally related to high interfacial tensions preventing optimal well's clean up and cost-effective achievable penetrations. This work presents a new well stimulation concept in which the carrying system is gas instead of liquid. The overall study will be presented in 2 parts. Part I will discuss basic physical questions related to treatment durability as a function of deployment method (continuous dispersion vs liquid batch gas displacement) for at least two damage scenarios of particular interest: asphaltene deposition and condensate blockage. A basic mechanistic simulation is also presented for benefit estimations at well scale. Part II will focus on field trials design and execution using micellar and/or fluoropolymer type of chemistries that exhibited the best performance when tested under laboratory conditions.
Experiments herein presented were done in formation sandstone cores simulating reservoir conditions. It is shown that natural gas when used as the carrying system to deploy conventional asphaltene dissolution and condensate removal chemistries enhances both Ko re-establishment and treatment durability as compared to equivalent liquid-based applications. Additional studies are being performed to maximize the effectiveness of the GaStim concept. Sensibilities to gas type (N2, CO2), added chemical and dosages as long as field trial documentation will be presented in part II of the present work.
GaStim concept is presented as a novel chemical stimulation technique potentially allowing deeper penetrations and better chemical adsorptions. Its potential, although still not fully undiscovered, is certainly supported by higher Ko reestablishment values and longer treatment durabilities observed.
Stimulation in Wells with Electric Submergible Pumps Increases Production and Save Costs without Damaging Pumps
Authors: Gallegos M. , Milne A. , Del Rio C. , Robles M. 
Published: April 2012

Abstract
Stimulating sandstone formations typically requires a mixture of hydrochloric acid (HCl) and hydrofluoric acid (HF) to dissolve formation damaging minerals. The HF reacts with and dissolves all HCl soluble minerals and, dissolves or partially dissolves siliceous materials such as bentonite and naturally occurring formation clays. Because these acid treatments are corrosive, it is common practice in low-pressure wells to pull out the electrical submersible pumps (ESPs) prior to performing a stimulation treatment to prevent damage to them. Doing so results in additional costs and deferred production.
In Ecuador, oil is produced from low- pressure sandstone reservoirs by using ESPs. In many of these reservoirs production is limited by scaling or fines migration. The low reservoir pressure often results in additional formation damage when during workovers because of the loss of completion fluid, emulsions, and clay instability. Many operators prefer to produce well with formation damage rather than expose the ESPs to corrosive fluids to remove the damage or generate additionally damage during a workover.
Using a non-acid chelating system (NACS) as the stimulation fluid combined with a placement technique made it possible to stimulate wells completed with ESPs or with corrosion sensitive completions, without needing to pull out the ESP for the stimulation treatment.
A laboratory study to assess the corrosion of each component of an ESP exposed to different treating fluids (live and spent) for extended periods was undertaken. The NACS fluid was capable of both removing calcium scales and fines, and preventing fines migration while minimizng corrsoion.
The NACS stimulation fluid successfully treated more than 10 wells competed with ESPs. In many cases, production in these wells increased by 35%. In addition, the treatment cost was 70% less than treatments for which a workover rig was used. Moreover, deferred production was reduced from days to hours.
Because of the time and cost savings, this technique should be particularly beneficial in marginal fields, where rig availability and economics are often an issue.
Artificial Communication Between Compartmentalized Reservoirs to Maximize the Value with Existing Infrastructure in Offshore Fields
Authors: Martinez V. , Ascencio F. C. , Ley H. Cinco , Lozada M. 
Published: April 2012

Abstract
This paper aims a solution to improve dynamic connectivity between regions in compartmentalized reservoirs. The proposal is to drill horizontal wells whose main objective is to communicate the zones where compartmentalization has been detected. The fluid flow between compartments will occur due to the potential difference existing between them. The flowrate will depend on the petrophysical properties of reservoir, physicochemical properties of fluids and the design of horizontal well. The work develops a mathematical model that represents the potential behavior of each compartment over time when they are communicated through a horizontal well. It considers the special application for gas cap systems and it presents an example, which demonstrates the impact and benefits of this solution. The implementation of this proposal will help exploiting the hydrocarbons reservoir through the existing infrastructure in adjacent regions, thus, reducing or eliminating the requirement of new infrastructure and extending the lifespan of existing infrastructure, thereby maximizing the value and recovery of the fields, which can represent great economic benefits for many oil companies.
Enhance Platform Integrity by a Real-time Equipment Availability Monitoring Workflow
Authors: Machado L. , Costa M. , Correa S. , Regina E. , Herdeiro M. 
Published: April 2012

Abstract
One of the greatest strategic focuses of the oil industry is the maintenance area, which is directly responsible for the availability of equipment involved in the production process. It affects the platform operational efficiency and consequently, the company results. Those results will increase with increases in effective maintenance management. In addition, the oil industry has experienced a wave of process optimization and systematization through new tools that support management and decision-making processes.
This paper presents a workflow that enables remote monitoring of onboard equipment status (operating, stand-by, or unavailable), identification of equipment with elevated risk of target violations, and the calculation and analysis of availability indicators. It also provides access to the historical data of unavailability events for the equipment monitored. This workflow performs real-time equipment monitoring through several logic implementations using sensor signals, automatically recording events at the moment that the equipment shows to be unavailable, and sending alerts to personnel responsible for the equipment. In addition, some equipment that do not have sensor signals, which enables real-time monitoring, were included in the daily routine through a manual process of entering unavailability events in the system enabling a further analysis of the historical unavailability. Consequently, the availability indicator is calculated in real time on the basis of these unavailability events. During the monthly indicator consolidation process, the system generates a report of the equipment that functioned below the set target, enabling a focus on the treatment of the most critical equipment during maintenance and asset integrity meetings.
The workflow solution provides several benefits. First, it monitors the status of equipment in real time, enabling a faster return to normality. It also captures unavailability events automatically, and records and provides details about these events. The workflow also monitors availability indicators, monitors major unavailability events by exception and historical analyses, and ensures the integrity of the process plant.
Decision-Making Breakthrough Technology
Authors: Fernandez Damian A. , Vidal Matias J. , Festini Diego E. 
Published: April 2012

Abstract
Nowadays the industry requires higher operational efficiency and reservoir management optimization. It is essencial for making decisions to have information in a timely and integral manner.
The objective of this report is to demonstrate how the use of surveillance together with specific well management software came to be an important tool to take more accurate and faster decisions. It provides access to real time events and data, and also makes it easier to have an efficient and cooperative interaction between people in different areas, optimizing the task flow. This research describes the hardware and software components of the surveillance system and analyzes how the different modules of the management software work.
The results show how minimizing downtime through early events detection increased production and how the efficient use of resources reduced the lifting cost. This all translates to a better operational organization and makes it possible to act proactively by identifying potential problems or failures in wells.
In conclusion, having a digitalized oil field allows us to reach agreement easily and to concentrate efforts in solving problems, through the close relationship that is achieved between technology, processes and people.
This technology has a broad application range because it integrates the different operational levels while minimizing financial risks. The use of this technology can be leveraged to most of the current artificial lift systems and it is compatible with many of the drivers/interfaces available in the market.
This helps to reinforce in Argentina the incorporation of technology as a management tool for the exploitation of oil fields. It can boost corporate social responsibility, by having a significant impact on profits with the available resources and integrating the organization towards operational excellence.
An Integrated Pathway to Enhance Human Talent
Authors: Hasselmeyer J. , Lobo L. Vielma 
Published: April 2012

Abstract
Managing Human Resources Development with an integrated and systematic approach is the key to individual and business success as it enables managers to identify and use the talent strengths for the benefit of the organization while motivating individuals towards their personal and professional growth.
Based on the though above mentioned, we developed a Continuous Human Development Model (CHDM)*, anchored to the Strategic Business Plan, with emphasis in the Human Resource Strategic Direction. The Model is composed of five interrelated processes. The first one is related to the Recruiting and Selection of Talents and the Induction - Training required before they are appointed to the organization's positions. The three following represent the Core of the CHDM: Education and Training based on a previous Competencies level measurement, Career Development and Reward linked to Performance Appraisal. The Training based on Competencies process favors the identification of gaps between the employee's knowledge and the level they require to generate superior deliveries. The Career Development process includes: The Individuals Development Plan which is designed based on career paths and employee potentiality, and the Succession Plan for each key position, to assure the availability of candidates. The Reward, linked to Performance Appraisal, aligns individual to the Business Strategy, Mission and Vision. Last but not least, is the Retirement process which is conceived to prepare and enable employees to cope satisfactorily with a new environment and a different lifestyle.
The Model described was put into place by the Human Resource Department, of the Exploration and Production Division of two National Oil Companies located in South America and Central America, generating benefits to the business such as availability of: technical and managerial talents due to early talent identification, career paths and chart replacements for key positions and relay generation. It also brought some additional and intangible benefits like personal alignment to the organization strategic guidelines and reinforcement of a goal oriented culture, among others.
Water Coning in Naturally Fractured Carbonate Heavy Oil Reservoir – A Simulation Study
Authors: Pérez-Martinez E. , Rodriguez-de la Garza F. , Samaniego-Verduzco F. 
Published: April 2012

Abstract
During production in a naturally fractured reservoir with natural water influx, under certain flow conditions an imbalance can be generated between gravity and viscous forces within the fracture system. This phenomenon is characterized by the gradual growth of a cone of water in the vertical and radial directions. When the radial growth of the cone base at the oil-water contact reaches the drainage radius, the cone of water reaches its maximum height. After this, the oil-water interface advances without suffering deformation in the pseudo stationary regime. However, when this interface is a short distance from the bottom of the completion interval, the movement of the oil-water interface accelerates and water flows into the well. This phenomenon may shorten the well's life due to the complexity of oil-water separation offshore and resulting increases in operating costs.
In many of the Cretaceous formations of the offshore Mexico Bay of Campeche, oil recovery is limited at the top by the presence of a gas-oil contact and at the bottom by an oil-water contact. To recover the remaining hydrocarbon reservoirs it is necessary to: (1) define the optimal operating range which should be established for each well to delay water and gas breakthrough and (2) to schedule the necessary infrastructure to handle high production rates of water and gas as the field matures.
The objectives of this work are to:
Model in detail the water coning in the porous fracture system using a fine radial grid, with one meter thick layers concentric around the well, and 2 inches thick layers in the annulus, with and without cement.
Obtain an equation to determine the maximum height of water coning, the time it takes to form the cone, and the well shut-in time necessary to undo or "heal" the water cone.