The Experts below are selected from a list of 900 Experts worldwide ranked by ideXlab platform
Flori, Ralph E. - One of the best experts on this subject based on the ideXlab platform.
-
Using an Analytical Model to Predict Collapse Volume during Drilling: A Case Study from Southern Iraq
Scholars\u27 Mine, 2019Co-Authors: Abbas A. K., Manhalawi A., Alameedy U., Flori, Ralph E.Abstract:Zubair Formation is one of the richest petroleum systems in Southern Iraq. This formation is composed mainly of sandstones interbedded with shale sequences, with minor streaks of limestone and siltstone. Borehole collapse is one of the most critical challenges that continuously appear in drilling and production operations. Problems associated with borehole collapse, such as tight hole while tripping, Stuck Pipe and logging tools, hole enlargement, poor log quality, and poor primary cement jobs, are the cause of the majority of the nonproductive time (NPT) in the Zubair reservoir developments. Several studies released models predicting the onset of borehole collapse and the amount of enlargement of the wellbore cross-section. However, assumptions involved in these models have limited their applications to very specific scenarios. In this study, an analytical solution for determination of the volume of collapse during drilling is presented based on changes in the geometry of boreholes. The approach can be used in conjunction with different failure criteria to estimate the collapse onset in the presence of formation strengths and principal stresses. The study highlighted how the integration of information from different sources and disciplines were able to estimate the shear failure induced on the borehole wall during drilling
-
Stability Analysis of Highly Deviated Boreholes to Minimize Drilling Risks and Nonproductive Time
'ASME International', 2019Co-Authors: Abbas, Ahmed K., Flori, Ralph E., Alsaba MortadhaAbstract:The Lower Cretaceous Zubair Formation is a regionally extended gas- and oil-producing sandstone sequence in Southern Iraq. Due to the weak nature of the Zubair Formation, the lack of wellbore stability is one of the most critical challenges that continuously appears during the drilling development operations. Problems associated with lack of wellbore stability, such as the tight hole, shale caving, Stuck Pipe, and sidetracking, are both time-consuming and expensive. This study aimed to construct a geotechnical model based on offset well data, including rock mechanical properties, in situ stresses, and formation pore pressure, coupled with suitable rock failure criteria. Mohr-Coulomb and Mogi-Coulomb failure criteria were used to predict the potential rock failure around the wellbore. The effect of the inclination and azimuth of the deviated wells on the shear failure and tensile failure mud weights was investigated to optimize the wellbore trajectory. The results show that the best orientation to drill highly deviated wells (i.e., inclinations higher than 60 deg) is along to the minimum horizontal stress (140 deg). The recommended mud weight for this selected well trajectory ranges from 1.45 to 1.5 g/cc. This study emphasizes that a wellbore stability analysis can be applied as a cost-effective tool to guide future highly deviated boreholes for better drilling performance by reducing the nonproductive time
-
Intelligent Prediction of Stuck Pipe Remediation using Machine Learning Algorithms
Scholars\u27 Mine, 2019Co-Authors: Abbas, Ahmed K., Flori, Ralph E., Almubarak H., Dawood J., Abbas H., Alsaedi A.Abstract:Stuck Pipe is still a major operational challenge that imposes a significant amount of downtime and associated costs to petroleum and gas exploration operations. The possibility of freeing Stuck Pipe depends on response time and subsequent surface action taken by the driller during and after the sticking is experienced. A late and improper reaction not only causes a loss of time in trying to release Stuck Pipe but also results in the loss of an important portion of expensive tubular, downhole equipment and tools. Therefore, a fast and effective response should be made to release the Stuck Pipe. Investigating previous successful responses that have solved Stuck Pipe issues makes it possible to predict and adopt the proper treatments. This paper presents a study on the application of machine learning methodologies to develop an expert system that can be used as a reference guide for the drilling engineer to make intelligent decisions and reduce the lost time for each Stuck Pipe event. Field datasets, including the drilling operation parameters, formation type, and fluid mud characteristics, were collected from 385 wells drilled in Southern Iraq from different fields. The new models were developed to predict the Stuck Pipe solution for vertical and deviated wells using artificial neural networks (ANNs) and a support vector machine (SVM). The results of the analysis have revealed that both ANNs and SVM approaches can be of great use, with the SVM results being more promising. These machine learning methods offer insights that could improve response time and strategies for treating Stuck Pipe
-
Collapse Volume Log Estimation using Image Processing Approach
Scholars\u27 Mine, 2018Co-Authors: Alkamil E. H. K., Flori, Ralph E., Eckert AndreasAbstract:Wellbore collapse as a result of severe borehole breakouts represents a major problem in many cases. In order to quantify the risk associated to wellbore collapse a reliable estimate of the collapse volume is necessary. In this study, a novel approach determining the depth/area/volume of collapse failure by using image processing approach is presented. Since image processing can be applied to any result set, the proposed approach is independent of any failure criterion (such as Mohr Coulomb, Mogi-Coulomb and Modified Lade criteria) and very versatile. For hydrocarbon fields where Mechanical Earth Modeling (MEM) approaches capable of predicting the spatial distribution of horizontal stresses exist, the presented image processing approach is utilized to generate an automated log of collapse volume while drilling. Based on this log, mud pressure adjustments can be undertaken while drilling a new well based on collapse volume. The main contribution of this work is the estimation of a real-time collapse volume log while drilling. It can help the drilling engineers in evaluating the mud weight effect on the hole cleaning efficiency to avoid Stuck Pipe problems. In addition, knowledge of the collapse volume provides better estimates on the required mud and cement volumes
-
Development of a Geomechanical Model for Drilling Deviated Wells through the Zubair Formation in Southern Iraq
Scholars\u27 Mine, 2018Co-Authors: Abbas A. K., Al-asadi Schlumberger Y. M. B., Alsaba M., Flori, Ralph E.Abstract:The Zubair Formation is the most prolific reservoir in Iraq, which is comprised of sandstones interbedded with shale sequences. Drilling deviated boreholes in this formation has always been a challenge due to the weak nature of the shale sequence. Historically, over 90% of wellbore problems in the Zubair Formation are due to wellbore instability. These wellbore instability problems, such as hole collapse, tight hole, Stuck Pipe, and sidetracks results in increasing the nonproductive time (NPT) and well costs. The present study aims to construct a calibrated post-drill 1-D mechanical earth model (MEM) that can be used to conduct a comprehensive geomechanical analysis of the Zubair Formation. A practical methodology was detailed for (1) constructing the 1-D MEM by using data from several open hole logs and (2) calibrating such a model using all the available data (e.g., observations of wellbore failures, measurements of well testing, laboratory test results of rock mechanical properties, etc.). Three failure criteria (i.e., Mohr-Coulomb, Mogi-Coulomb, and Modified Lade) were used to perform a root cause analysis of borehole breakouts and to address the minimum required mud weight to minimize wellbore instability-related issues for different well trajectories. The wellbore failure analysis showed that the mud weight, that was used previously, is insufficient to support the rock on the wellbore wall, and it is not appropriately adjusted according to the variation in the wellbore azimuth and inclination. In addition, the heterogeneity of the Zubair Formation and the inappropriate drilling practice have magnified the severity of the drilling problems. The predictions resulting from this study can be used as cost-effective tools when planning for future neighboring deviated wells to create better drilling efficiency by reducing the nonproductive time and well costs
Sundja A. - One of the best experts on this subject based on the ideXlab platform.
-
Evaluasi Penyebab Pipa Terjepit pada Sumur M di Lapangan “X” di Pertamina EP
Trisakti University, 2015Co-Authors: Akrimah A., Satyawira B., Sundja A.Abstract:Pada operasi pemboran Sumur M di Lapangan X, banyak dijumpai berbagai macam masalah yang menghambat jalannya operasi pemboran sumur tersebut. Salah satu masalah pemboran yang dijumpai pada Sumur M ini adalah terjepitnya rangkaian pipa bor. Terjepitnya rangkaian pipa bor akan menghambat penyelesaian sumur yang akanmengakibatkan meningkatnya waktu dan biaya pemboran dari yang telah direncanakan. Dalam tugas Akhir ini akan diteliti mengenai penyebab terjepitnya rangkaian pipa bor serta penanggulangan yang telah dilakukan. Hal - hal yang dapat menyebabkan pipa terjepit seperti, aspek lumpur,aspek rangkaian alat pemboran, kestabilan lubang bor, jenis formasi dan lithologi batuan juga. Jenis – jenis pipa terjepit seperti diffrential sticking, mechanical, key seat, pack off. Metode yang dilakukan dalam menanggulangi pipa terjepit seperti metode renggang lepas, sirkulasi,Work on Pipe, dan metode terakhir Jarring. Evaluasi yang dilakukan pada tugas Akhir ini adalah berkaitan dengan lumpur yang digunakan beserta dengan rheologynya dan alat pemboran yang digunakan. Hal ini dilakukan, sehingga operasi pemboran dapat terus dilanjutkan dan penyelesaian sumur dapat dilakukan dengan baik. Stuck Pipe pada Sumur M terjadi pada trayek 8 ½ ” dengan klasifikasi terdapat bridging cutting akibat dari hole cleaning yang tidak optimal. Dan putusnya HWDP 5” dikarenakan washout ditandai adanya lubang dan pola gerusan pada pin HWDP 5”. Metode yang dilakukan dalam penanggulangan Stuck Pipe pada sumur M ini, yaitu dengan jarring, dikarenakan dengan metode work on Pipe, sirkulasi, dan reconnect, namun pipa tidak dapat terlepas. Pemboran dilanjutkan dengan fishing job untuk mencapai target displacement yang direncanakan
-
Evaluasi Terjepitnya Rangkaian Pipa Pemboran pada Sumur “Jh-151” Lapangan X di PT. Pertamina Ep
Trisakti University, 2015Co-Authors: Situmorang K. R., Satiyawira B., Sundja A.Abstract:Operasi pemboran yang dilakukan tidak selalu berjalan dengan lancar, adakalanya timbul masalah yang dapatmenghambat jalannya operasi pemboran tersebut. Masalah-masalah yang berhubungan dengan pemboransumur minyak sebagian besar disebabkan oleh karena gangguan terhadap tegangan tanah (earth stress) disekitar lubang bor yang disebabkan oleh pembuatan lubang itu sendiri dan adanya interaksi antara lumpurpemboran dengan formasi yang ditembus. Tegangan tanah bersama tekanan formasi berusaha untukmengembalikan keseimbangan yang telah ada sebelumnya dengan cara mendorong lapisan batuan kearahlubang bor. Lubang bor dijaga agar tetap stabil dengan cara menyeimbangkan tegangan tanah dan tekanan poridi satu sisi dengan tekanan lumpur pemboran di sekitar lubang bor dan komposisi kimia lumpur bor pada sisiyang lain. Setiap kali keseimbangan ini diganggu maka timbullah masalah-masalah di lubang bor. Salah satumasalah itu adalah terjepitnya rangkaian pemboran. Hambatan operasi pemboran pada sumur menyebabkanwaktu operasi menjadi lebih lama dari yang direncanakan, serta meningkatnya biaya pemboran sampai dua kalilipat dari biaya yang dianggarkan. Hambatan pemboran berupa rangkaian terjepit oleh guguran formasi ( HolePack-Off), merupakan hambatan utama yang terjadi pada interval 8 ½”. Metode yang dilakukan dalampenanggulangan Stuck Pipe pada sumur ini, yaitu dengan back off, dikarenakan dengan metode work on Pipe,sirkulasi, dan perendaman, namun pipa tidak dapat terlepas. Pemboran dilanjutkan dengan side track untukmencapai target displacement yang direncanakan
Time André - One of the best experts on this subject based on the ideXlab platform.
-
Dual gradient drilling - simulations during connection operations
University of Stavanger Norway, 2014Co-Authors: Time AndréAbstract:Master's thesis in Petroleum engineeringAs oilfields are ageing and depleting, operators are forced to start searching for oil in more hostile environments. These new environments can introduce new drilling challenges. Prospects like ultra deep water reservoirs and depleted offshore reservoirs are difficult to drill with conventional drilling. This has lead the industry to developing the Dual Gradient Drilling (DGD) system. DGD is an unconventional drilling method and it is classified as a Managed Pressure Drilling (MPD) technique. By using fluids of varying density, DGD can provide the desired annular pressure profile in order to increase well performance, improve personnel safety and reduce Non Productive Time (NPT). Four major dual gradient drilling methods, along with the most important equipment, will be presented in this thesis. The various MPD technologies tries to compensate for the pressure variations experienced in the wellbore during connections. These pressure variations can cause formation fracturing, lost circulation, Stuck Pipe and more. By utilizing the DGD system the pressure variation related to connection operations can be significantly reduced. Although this new technology has several advantages over conventional drilling, it also has its challenges. To study the effects the DGD system has on downhole pressure during connection operations, the Kaasa model is used to simulate a DGD well and the results are compared to an MPD well
-
Dual gradient drilling - simulations during connection operations
University of Stavanger Norway, 2014Co-Authors: Time AndréAbstract:As oilfields are ageing and depleting, operators are forced to start searching for oil in more hostile environments. These new environments can introduce new drilling challenges. Prospects like ultra deep water reservoirs and depleted offshore reservoirs are difficult to drill with conventional drilling. This has lead the industry to developing the Dual Gradient Drilling (DGD) system. DGD is an unconventional drilling method and it is classified as a Managed Pressure Drilling (MPD) technique. By using fluids of varying density, DGD can provide the desired annular pressure profile in order to increase well performance, improve personnel safety and reduce Non Productive Time (NPT). Four major dual gradient drilling methods, along with the most important equipment, will be presented in this thesis. The various MPD technologies tries to compensate for the pressure variations experienced in the wellbore during connections. These pressure variations can cause formation fracturing, lost circulation, Stuck Pipe and more. By utilizing the DGD system the pressure variation related to connection operations can be significantly reduced. Although this new technology has several advantages over conventional drilling, it also has its challenges. To study the effects the DGD system has on downhole pressure during connection operations, the Kaasa model is used to simulate a DGD well and the results are compared to an MPD well
Mohammed Gad Elsonbatty - One of the best experts on this subject based on the ideXlab platform.
-
propylene glycol mono and di stearates as water in oil emulsifiers for oil well drilling fluids
Egyptian Journal of Petroleum, 2018Co-Authors: M M Dardir, Hany Elsayed Ahmed, Abd El M Fattah, M E Hassan, Hesham Abu Seda, Mohammed Gad ElsonbattyAbstract:Abstract The objective of drilling operation is to drill, evaluate and complete a well that will produce oil and/or gas efficiently. The responsibility for performing these functions is held by using drilling mud. The research will focus on the oil base mud system due to the importance of that kind of drilling fluid which helped to address several drilling problems such as formation clays that react, swell or slough after expose to WBFs, increasing down hole temperatures, contaminants, Stuck Pipe, torque and drag. The research will rely on an economical-low cost prepared emulsifiers that used as W/O emulsifiers for oil base mud instead of the imported emulsifier. The new prepared emulsifiers provide an excellent options with emulsification power for oil-based mud that formulated from diesel oil and water. The nonionic emulsifiers were prepared through the esterification reaction of propylene glycol (1 mol) and stearic acid (1 mol) and/or (2 mol), the products were two oil soluble nonionic emulsifiers with hydrophilic/lipophilic balance (HLB) of 3.4 and 2.8 respectively. The chemical structure was confirmed using elemental analysis, FTIR and 1H NMR. The new prepared emulsifiers were evaluated as primary emulsifiers for oil – base mud and the results were compared with the currently used primary emulsifier. The obtained results exhibited interesting rheology properties and shear-thinning behavior, yield value, thixotropy, gel strength and filter loss.
-
Propylene glycol mono and di stearates as water in oil emulsifiers for oil-well drilling fluids
'Elsevier BV', 2018Co-Authors: M M Dardir, Hany Elsayed Ahmed, Abd El M Fattah, M E Hassan, Hesham Abu Seda, Mohammed Gad ElsonbattyAbstract:The objective of drilling operation is to drill, evaluate and complete a well that will produce oil and/or gas efficiently. The responsibility for performing these functions is held by using drilling mud.The research will focus on the oil base mud system due to the importance of that kind of drilling fluid which helped to address several drilling problems such as formation clays that react, swell or slough after expose to WBFs, increasing down hole temperatures, contaminants, Stuck Pipe, torque and drag.The research will rely on an economical-low cost prepared emulsifiers that used as W/O emulsifiers for oil base mud instead of the imported emulsifier. The new prepared emulsifiers provide an excellent options with emulsification power for oil-based mud that formulated from diesel oil and water.The nonionic emulsifiers were prepared through the esterification reaction of propylene glycol (1 mol) and stearic acid (1 mol) and/or (2 mol), the products were two oil soluble nonionic emulsifiers with hydrophilic/lipophilic balance (HLB) of 3.4 and 2.8 respectively. The chemical structure was confirmed using elemental analysis, FTIR and 1H NMR.The new prepared emulsifiers were evaluated as primary emulsifiers for oil – base mud and the results were compared with the currently used primary emulsifier. The obtained results exhibited interesting rheology properties and shear-thinning behavior, yield value, thixotropy, gel strength and filter loss. Keywords: Drilling fluids, Drilling mud, Filtration loss, Gel strength, Rheology, Propylene glycol stearat
V Aurifullah - One of the best experts on this subject based on the ideXlab platform.
-
field based criteria for the design of safe mud weight window
SPE Technical Symposium of Saudi Arabia Section, 2005Co-Authors: M A Mohiuddin, K Khan, Abdulaziz Almajed, Abdulazeez Abdulraheem, V AurifullahAbstract:Field based parameters like initial mud weight used for drilling, mud weight increment and problems per well were used to analyze wellbore instability, identify different instability mechanisms and design safe mud weight window for drilling horizontal wells. These parameters were used first on the drilling data of vertical wells to develop the procedure for the analysis of wellbore instability and identify the mechanism of instability. The developed procedure was then applied to the drilling data of directional wells to show the dependence of mud weight on the inclination and azimuth of the well. Finally, the procedure was applied to horizontal wells data along with the concept of critical washouts to infer the safe mud weight window. The safe mud weight window is validated on another set of drilling data showing 90% success rate. Background Wellbore instability manifests itself in different ways like hole pack off, excessive reaming, overpull, torque and drag, sometimes leading to Stuck Pipe that may require plugging and side tracking. This requires additional time to drill a hole, driving up significantly the cost of reservoir development. In case of offshore fields, loss of hole is more critical due to the limited number of holes that can be drilled from a platform. Drilling an ingauge hole is an interplay of two factors: uncontrollable and controllable. Uncontrollable factors are the earth stresses (horizontal and vertical), pore pressure and rock strength. Controllable factors include mud weight, wellbore azimuth and inclination. A proper drilling program optimizes the controllable factors with the knowledge of uncontrollable factors. It is well known in the rock mechanics literature that the change in mud weight with the angle of inclination depends on the in-situ stresses. If a normal stress regime is present, then the horizontal wells are the most difficult to drill, hence the mud weight has to be increased with the angle of inclination. However, for other stress regimes, the same is not true. In many a cases factors like magnitude of the maximum horizontal insitu stress and rock strength variations are not known. Under such circumstances, the safe mud weight window predicted using estimated parameters and available commercial software is often not realistic. If the wellbore instability is encountered, the drilling data accumulated for the previous wells can be used to predict the safe mud weight window. Some pertinent studies using drilling data and laboratory evaluated rock strength are reviewed here. Santarelli et al., (1996) presented the wellbore instability occurring in a developed field in Italy. The drilling problems were back analyzed with respect to the mud system used, azimuth, and stress regime. More drilling problems like reaming and Stuck Pipe occurred in one particular azimuth which corresponded with the maximum horizontal stress. In the absence of stress direction and magnitude for the field, the anisotropic distribution of stress field came to knowledge. The non inhibitive water based mud gave better results compared to other mud system. The standard drilling practices planned during appraisal drilling were continued with few modifications.
