See the entire March 2012 issue.
See the current issue at http://www.spe.org/go/spedc.
Hydraulic Fracturing: 2012 and Beyond
It is a good time to be in the oil industry. The rig count, drilling activity, and oil prices are high, and shale plays are a significant reason for each. And, because it is shale, it is an especially good time to be a completion engineer!
Even though we have been able to make these unconventional reservoirs economic by drilling horizontal wells and by multistage fracturing, it is important for us to realize (especially with low gas prices) that there is still plenty to learn about shale fracing (not spelled “fracking”). Buzz words fly around the industry: complex fractures, brittle vs. ductile shale, proppant transport in slickwater, and more. Each is a start, but what I challenge everyone to do is to ask the questions: What is really happening when we are fracturing the various shale plays; and how do we model it so that
we can predict and optimize performance?
Economic and political implications of shale are enormous. The USA recently, for the first time in many years, became a net exporter of energy. The USA has clear shale development advantages compared with other countries at this time because it has the rigs, hydraulic horsepower, personnel, and a long history of hydraulic fracturing.
But truth be told, there are disadvantages that must be dealt with. The USA is dealing with an oversupply of gas, which is reducing prices and making shale-gas plays marginally economical. To date, despite industry efforts, there still is no political will to substitute fuel sources on a large scale, create a widespread gas-fueling infrastructure, or increase automobile shale-gas usage appreciably.
So even though it is a good time to be in the oil field, remember that as completion engineers it is our job/duty to understand what is happening downhole when we are fracturing—Do we really have complexity? Does complexity occur in every shale interval or just the brittle ones? Does proppant “turn the corner” and go into the natural fractures? Knowing the answers to these and other questions can make the economics of shale plays become even better.
Read the paper synopses in the March 2012 issue of JPT.
Karen Olson, SPE, is the Completion Expert for Southwestern Energy. She has worked in the oil industry for 28 years, including positions with the Western Company of North America; Mobil E&P, working in west Texas, the Gulf of Mexico, and Norway; and most recently with BP as a Deepwater Completion Engineering Team Leader. Olson has written and presented many SPE papers and has been a discussion leader at SPE workshops and forums. She has served on several SPE committees and serves on the JPT Editorial Committee. Olson earned a BS degree in petroleum engineering from Louisiana State University and an MS degree in petroleum engineering from Texas A&M University.
Since the first downhole electric measurement was made in 1927 by the Schlumberger brothers (first electrical-resistivity well log), the oil/gas industry has been striving to develop and improve new tools and sensors for downhole measurements. Indeed, these sensors aim at measuring many parameters, such as physical properties of rocks and fluids (formation evaluation), wellbore position (inclination and azimuth), or downhole drilling-mechanics conditions. Over the last 12 months, I have been impressed by the number of papers and news articles dealing with drilling mechanics and with vibration-data measurement, transmission, processing, and interpretation. Dynamics and vibration events still are responsible for high nonproductive time (NPT) (e.g., tool failures in many cases) and suboptimal drilling performances. With advances in electronics components, tool reliability, battery technology, and sensors, many companies have begun to develop their own memory-based drilling-measurement tools and to offer the associated service (data processing and interpretation) to operators to maximize drilling efficiency and, thus, reduce NPT.
These downhole drilling-mechanics-measurement tools, rated up to 150°C, generally integrate the following sensors: bending moment, vibration (three-axis accelerometers), weight on bit, torque on bit, annular pressure, temperature, and magnetometers (downhole rotational speed). Data are stored in a memory-based subassembly powered by a lithium-based battery (capacity up to 200 hours), or are transmitted to the surface (by use of mud-pulse, electromagnetic, or wired-pipe telemetry). The latest developments include ingenious sensors placed in the pin of the drill bit (avoiding an extra subassembly in the bottomhole assembly). Though measurements originally were captured close to the bit in the bottom portion of the drillstring, the industry has identified the need to have multiple sensors deployed all along the string (from the bit to the topdrive) to monitor continuously and anticipate any drilling event.
This outbreak of downhole-sensor technology is good news for the industry because it will probably accelerate the understanding of what is happening downhole even more, thus improving the overall drilling efficiency. Downhole drilling measurements should not be limited to only high-cost environments, but should be used in the early stage of the field development to accelerate the learning curve and, thus, optimize the drilling process for the next wells. Even though some downhole drilling and dynamics tools were developed in the 1980s, the industry now has more-accurate sensors, better physical models, and more computational power to process and analyze this huge amount of drilling data.
Read the synopses in the February 2012 issue of JPT.
Stéphane Menand, SPE, is Managing Director of DrillScan US. Previously, he held a research position at Mines ParisTech University. Menand has 14 years of experience as an R&D project manager in drilling engineering–more specifically in directional drilling, drillstring mechanics (torque, drag, and buckling), drilling dynamics, and drill-bit performance. He has authored several SPE and other technical papers and holds several patents. Menand earned a PhD degree in drilling engineering from Mines ParisTech University. He serves on the JPT Editorial Committee, the SPE Books Development Committee, and the SPE Drilling and Completions Advisory Committee.
Real-time data is not about well control, it is about well control avoidance. Recent catastrophic blowouts have underscored the value of real-time data and, more importantly, they have also underscored the value of having the right kind of experience to understand well data interpretation in real time.
What is the well telling us? How do we use real-time data to ensure a stable wellbore? Real-time monitoring integrated with rigorous total well control analysis is required to embrace and achieve continuous improvement and ensure the safest possible environment. Next generation monitoring requires a step change that includes hazards avoidance as a precursor to drilling optimization.
Real-time data can be used effectively to avoid, minimize, and better manage drilling and completion operations. They can also provide the foundational support to improve training in the industry as well as develop hands-on simulators for hazards avoidance.
Read the entire article in the January 2012 issue of JPT.
Procrastination: Is it too many things going on at once that causes us to rush to meet deadlines, or makes us forget to complete important tasks in a timely manner, or even try to do too many things at once, resulting in nothing getting done correctly? You probably are wondering how this relates to well control. In our work schedules, we all are faced with situations in which we are required to complete multiple concurrent tasks. This often is the case when we rush to finish drilling a problem well so that we can get the drilling rig moved to the next location and turn this well over to the completions team. Multiple activities must be completed concurrently that, individually, are relatively simple, but each activity requires the attention of the driller, tool pusher, company man, and others on the crew. When one of these tasks begins to go awry, our attention may be on something else, and we can miss important warnings until it is too late to avoid a disaster.
What is the point? Once again, I will use the Macondo blowout as an example. To leave the well in a position to be completed by another crew, mud had to be removed from the riser and top of the well and be replaced with seawater. A spacer was pumped between the mud and seawater to prevent mixing of the seawater and mud. This is a simple enough operation, it seems, but when seawater is being pumped into the well, mud has to be pumped onto a workboat to prevent the pits from running over, and the spacer is being dumped overboard; keeping track of how much of each fluid is going where becomes a daunting task. Could this have been a contributing factor in not recognizing the beginning of the kick?
Jerome Schubert, SPE, is an assistant professor in the Harold Vance Department of Petroleum Engineering at Texas A&M University. He has more than 30 years’ experience with Pennzoil, Enron Oil and Gas, the University of Houston– Victoria Petroleum Training Institute, and Texas A&M University. Schubert earned BS, ME, and PhD degrees in petroleum engineering from Texas A&M University. He is a coauthor of Managed Pressure Drilling and the author of more than 35 technical papers. Schubert serves on the JPT Editorial Committee and has served on several SPE committees and as a Technical Editor for SPE Drilling & Completion. He serves as Faculty Advisor for Pi Epsilon Tau. Schubert is a registered professional engineer in Texas.
View the entire contents of the December 2011 issue.
Completion Design and Execution
151970-PA – Completing the First Big Bore Gas Wells in Lunskoye–a Case History
C. Zerbst, SPE, and J. Webers, SPE, Sakhalin Energy Investment Company Limited
134326-PA – Numerical Simulations of Sand-Screen Performance in Standalone Applications
Somnath Mondal, SPE, and Mukul M. Sharma, SPE, University of Texas at Austin; and Rajesh A. Chanpura, SPE, Mehmet Parlar, SPE, and Joseph A. Ayoub, SPE, Schlumberger
Drilling and Completion Fluids
140868-PA – Development of Water-Based Drilling Fluids Customized for Shale Reservoirs
J.P. Deville, B. Fritz, and M. Jarrett, Halliburton
135166-PA – Protecting the Reservoir With Surfactant Micellar Drill-In Fluids in Carbonate-Containing Formations
Tianping Huang, SPE, James B. Crews, SPE, and David E. Clark, SPE, Baker Hughes
141447-PA – Stabilizing Viscoelastic Surfactants in High-Density Brines
R. van Zanten, SPE, Halliburton
130579-PA – Laminar and Turbulent Friction Factors for Annular Flow of Drag-Reducing Polymer Solutions in Coiled-Tubing Operations
Chinenye C. Ogugbue, SPE, and Subhash N. Shah, SPE, Well Construction Technology Center, University of Oklahoma
The last decade has seen significant change in many areas of the drilling business, particularly with bits and bottomhole assemblies. Rising drilling costs, more-complex and -demanding drilling environments, and the ever-present stimulus of provider competition are continuing to drive improved understanding and decision making in this area. The days when bits were seen as simple commodities, with their leverage on well time and cost unrecognized, are fading. And this is long overdue.
Particularly encouraging is the growing use of field-behavior modeling of the bit and drillstring under realistic conditions, and the development of knowledge- based tool-selection techniques, refined by an intensive study of field data. The migration toward deeper or more-tortuous well designs, often accompanied by simultaneous drilling and hole opening in regions in which vibration effects are prolific and are more punishing, is leading to more understanding and rigor. These are admirable trends that more-traditional operations can and should capitalize on, and sometimes are.
My learned colleague Graham Mensa-Wilmot wrote of these trends a year ago in this feature, correctly pointing out to us that “We have the key, let’s open the door.” Perhaps we can claim to have done so with some challenges and in some geographical areas (e.g., vibration diagnosis and mitigation in deepwater Gulf of Mexico operations). However, with other equally important challenges (quantitative optimizing of the rate of penetration comes to mind), fundamental understanding and rigorous methods are not so widespread; we are still operating with “pockets of excellence.” So, it is appropriate to lay another challenge to those managing drilling operations and providing drilling services–if your teams are relying on a fuzzy definition of downhole processes or on trial and error to deliver drilling performance, it is time to modernize–let’s have the current pockets of excellence show the rest of us the way.
Read the paper synopses in the December 2011 issue of JPT.
Martyn Fear, SPE, is General Manager of Drilling & Completions for Husky Energy’s Atlantic Region, Canada. He has more than 25 years’ experience in drilling optimization and operations management across a wide variety of international locations. Fear serves on the JPT Editorial Committee. He earned a BSc (Honors) degree in geological sciences from the University of Birmingham, England.
View the entire September 2011 issue of SPE Drilling & Completion
134563-PA – Continuing Application of Torque-Position Assembly Technology for API Connections
James P. Powers, SPE, ExxonMobil Development Company; and Michael S. Chelf, SPE, ExxonMobil Upstream Research Company
135462-PA – A Major Advancement in Expandable Connection Performance, Enabling Reliable Gastight Expandable Connections
Richard DeLange, SPE, Raju Gandikota, and Scott Osburn, SPE, Weatherford International
119468-PA – New Standard for Evaluating Casing Connections for Thermal-Well Applications
Jaroslaw Nowinka, SPE, and Dan Dall’Acqua, SPE, Noetic Engineering 2008
139829-PA – Casing Design With Flowing Fluids
Robert F. Mitchell, Halliburton
139824-PA – Lateral Buckling–The Key to Lockup
Robert F. Mitchell, Halliburton, and Tore Weltzin, Statoil