McDougall School of Petroleum Engineering

DRILLING RESEARCH PROJECTS

ADVISORY BOARD MEETING May 13th, 2013

EXECUTIVE SUMMARIES

THE

NIVERSITY ULSA

UTof

AGENDA

THE UNIVERSITY OF TULSA Drilling Research Projects Advisory Board Meeting

The DoubleTree Hotel at Warren Place

6110 S. Yale Avenue Tulsa, OK 74136

AGENDA

Monday, May 13th, 2013 CLASSIC CONTINENTAL BREAKFAST…………………………………………………..7:45 a.m. The DoubleTree Hotel at Warren Place Tulsa Learning Theater

INTRODUCTION Stefan Miska …………………………………………….………………………8:15 a.m. – 8:35 a.m. PROGRESS REPORTS Ali Karimivajargah ……………….........…...……..….…….........…...........…8:35 a.m. – 9:05 a.m. Pressure Signature of Gas Influx Feifei Zhang ……………………………………..…..….…….................…….9:05 a.m.- 9:30 a.m. Investigation of Cuttings Transport in 30~60 Degree Inclined Wells

Babak Akbari ………………………………….……........................………....9:30 a.m.- 10:00 a.m.

PDC Drillbit Modeling and Experiments

Oney Erge ….…...………….......…….…..……...……..…..….......….…....10:00 a.m.- 10:25 a.m. Effect of Free Drillstring Rotation on Pressure Losses Coffee Break ………………………………………….……....……….……..10:25 a.m.- 10:40 a.m.

Mojtaba Pordel Shahri …….…………..….……………..……................... 10:40 a.m.- 11:10 a.m. Stress Path Analysis in Depleted Sands

Zhaoyang Wang ………………………….……….......…….......….......…..11:10 a.m.- 11:35 p.m. Automatic Control of Drawworks Bahri Kutlu........…………......……….......…..….................…….....……....11:35 p.m.- 12:00 p.m. Rheology of Lightweight Drilling Fluids with Microsphere Additives LUNCH…………………….........................................................................12:00 p.m. - 1:10 p.m. Parkview Ballroom

INDUSTRY PRESENTATION Robert Mitchell- Halliburton Technology Fellow.......................................1:10 p.m. – 1:35 p.m. Discrete Torque and Drag Model Arild Saasen- Det Norske.........................................................................1:35 p.m. – 2:00 p.m. Annular Frictional Pressure Losses During Drilling- The Challenge of Research PROGRESS REPORTS Hao Zeng........…………......……….......…..….................……........……...... 2:00 p.m.- 2:25 p.m. Study of Effectiveness of LCM Materials

Mehran Mehrabi ………………………………..…..….............…..……..…… 2:25 p.m.- 2:50 p.m. Comparison of Steel, Aluminum, Titanium, and Composite Drill Pipe Sukru Durmaz ………………………………..………..…...................….…..... 2:50 p.m.-3:15 p.m. Displacement and Mixing of Fluids in Pipe Flow Coffee Break ……………………………………………..….......…….……....3:15 p.m.- 3:35 p.m. Reza Ettehadi Osgouei ........………………..............................…….......…3:35 p.m - 3:50 p.m. Review of Cuttings Transport Reza Ettehadi Osgouei …………….…………..…............……..…............. 3:50 p.m - 4:15 p.m. Annular Pressure Build Up (APB) Analysis-Optimization of Fluid Rheology RESEARCH PROPOSALS Ziad Alabdullatif …………………….…………..…..................................……4:15 p.m -4:30 p.m. The Effects of Nano-Particles on Foam Stability and Rheological Properties RESEARCH UPDATE- Mengjiao Yu ....…..……….….......................…….4:30 p.m. – 4:50 p.m. Shale Stability at Simulated Wellbore Conditions- Vahid Dokhani

Downhole Microchip Instrumentation System- Yuanhang Chen

Budget and Closing Comments ……………..…………………….....…....4:50 p.m. – 5:00 p.m. RECEPTION……….…………………………………………………………….7:00 p.m – 9:00 p.m.

The DoubleTree Hotel at Warren Place – Parkview Ballroom 6110 S. Yale Avenue Tulsa, OK 74136

THE UNIVERSITY OF TULSA Advisory Board Meeting

University of Tulsa

2450 E Marshall Tulsa, OK 74110

AGENDA

Tuesday, May 14th, 2013 NORTH CAMPUS All Visitors Assemble in Drill Building Conference Room………………….…….s……….9:00 a.m. Nicholas Takach/ Evren Ozbayoglu.……………………………………….….9:05 a.m. - 9:20 a.m. Tour Schedule & Facility Improvements FACILITY TOUR of NORTH CAMPUS....................................................9:20 a.m. – 11:00 a.m. ROUND TABLE DISCUSSION……………………………………………..11:00 a.m. – 11:30 a.m. LUNCH…………………………………………………………………………… 11:45 p.m.-1:00 p.m. The University of Tulsa South Campus- Gallery DRILLING RIG DEVELOPMENT DISCUSSION- OPTIONAL.....…………1:15 p.m. – 2:15 p.m. ***For those interested in the TUDRP Drilling Rig Facility INDIVIDUAL MEETINGS (upon request).……………………………………1:15 p.m. – 5:00 p.m. *********Next Advisory Board Meeting- November 4th and 5th , 2013*********** Doubletree Warren Place Hotel- Tulsa

MEMBER COMPANIES

BP Exploration 1977 Petrobras/Cenpes 1984 Statoil 1985 Halliburton Energy Services 1996 Baker-Hughes 1997 Schlumberger 1997 Weatherford 2000 ExxonMobil 2002 ConocoPhillips 2003 Shell E&P 2007 National Oilwell Varco 2007 Bureau of Safety and Environmental 2008 Enforcement (Formerly MMS) ENI 2008 Det norske oljeselskap ASA 2009 Tesco 2010 Hess 2011 SINOPEC 2011 3-M 2012

TUDRP PERSONNEL

TUDRP PERSONNEL EXECUTIVE DIRECTOR/ PRINCIPAL INVESTIGATOR: Stefan Miska SENIOR ASSOCIATE DIRECTOR: Nicholas Takach ASSOCIATE DIRECTORS: Mengjiao Yu Evren Ozbayoglu RESEARCH ASSOCIATE: Reza Ettehadi Osgouei PROJECT ASSISTANT: Paula Udwin PROJECT TECHNICIAN: Randy Darden Chad Murphy RESEARCH CONSULTANTS: Charles Alworth JJ Azar Jeremy Daily Siamack Shirazi Jim Sorem Steven Tipton RESEARCH ASSISTANTS: Babak Akbari, Ph.D. Candidate Ziad Alabdullatif, Ph.D. Student Yuanhang Chen, Ph.D. Student Vahid Dokhani, Ph.D. Student Sukru Durmaz, M.S. Candidate Oney Erge, M.S. Candidate Ali Karimivajargah, Ph.D. Candidate Bahri Kutlu , M.S. Candidate Mehran Mehrabi, M.S. Candidate Mojtaba Pordel Shahri, Ph.D. Candidate Zhaorui Shi, M.S. Candidate Zhaoyang Wang , M.S. Candidate Hao Zeng, M.S. Candidate Feifei Zhang, Ph.D. Student Shipping Address: Mailing Address: University of Tulsa University of Tulsa Drilling Research Projects Drilling Research Projects 2450 East Marshall Street 800 South Tucker Drive Tulsa, Oklahoma 74110 Tulsa, Oklahoma 74104 Telephone: (918) 631-5171 FAX: (918) 631-5009

Executive Summaries Table of Contents

EXECUTIVE SUMMARIES Research Projects Ali Karimivajargah Pressure Signature of Gas Influx Feifei Zhang Investigation of Cuttings Transport in 30~60 Degree Inclined Wells Babak Akbari PDC Drillbit Modeling and Experiments Oney Erge Effect of Free Drillstring Rotation on Frictional Pressure Losses Mojtaba Pordel Shahri Stress Path Analysis in Depleted Sands Zhaoyang Wang Automatic Control of Drawworks Bahri Kutlu Rheology of Lightweight Drilling Fluids with Microsphere Additives Hao Zeng Study of Effectiveness of LCM Materials Mehran Mehrabi Comparison of Steel, Aluminum, Titanium and Composite Drillpipe Sukru Drumaz Displacement and Mixing of Fluids in Pipe Flow Reza Ettehadi Osgouei Review of Cuttings Transport Reza Ettehadi Osgouei Annular Pressure Build Up (APB) Analysis-Optimization of Fluid Rheology Proposals Ziad Alabdullatif The Effects of Nano-Particles on Foam Stability and Rheological Properties

Pressure Signature of Gas Influx

Ali Karimivajargah

Pressure Signature of Gas Influx Investigator: Ali Karimi Sponsor: TUDRP Problem statement:

Managed Pressure Drilling (MPD) techniques rely on precisely controlling the annular pressure profile in the wellbore and hence enabling us to drill in narrow mud window (between pore and fracture pressure). Real time pressure data can be provided by mounting pressure sensors on wired drillpipe. By having access to such data at several locations along the wellbore, variations of the annular pressure profile during entrance of gas influx can help early gas detection and determining the location of the gas. Therefore, developing a simulator for accurate prediction of the annular pressure profile during gas influx is desired. In addition to early gas detection, this powerful tool can be used for designing and decision-making processes for MPD well control operations. Other outcomes of this modeling work include: enhancing safety in drilling, reducing non-productive time and improving MPD well control and automation in drilling.

Objectives • Early detection of gas influx and its location in the wellbore by mounting the pressure sensors on Wired Drill String

during MPD and conventional operations • Predicting variations in the annular pressure profile during entrance of gas influx to the wellbore by developing a

transient two-phase gas influx simulator • Providing a design and a decision-making tool for MPD well control operations • Predicting pressure profiles (pressure vs. time) at desired locations such as casing shoe • Predicting gas and liquid fractions along the wellbore, gas migration velocity, solubility of gas in OBM and SBM, pit

gain vs. time, and gas and liquid velocity distribution in the annular space • Validating the model with experimental and field data

Current Work • Modifying the available transient two-phase flow simulator to find the best response to gas influx during drilling in

managed pressure drilling operations • Introducing the chart methodology for MPD well control • Conducting sensitivity analysis to investigate the effects of important parameters during MPD well control • Comparing the available experimental data at TUDRP obtained from an 8" x 4.5" flow loop, with simulation results for

nearly vertical (15º) air-mud (non-Newtonian), two-phase flow to evaluate the simulator • Evaluate the simulator for slim hole well control scenarios by using available data sets from a 2.95" X 1.85" flow loop

Deliverables • A transient two-phase simulator for predicting pressure profile during gas influx, proposing methods for early gas

detection and determining gas location, and movement in the wellbore by using the pressure data obtained from WDP • A design and decision-making tool for MPD well control operations to find the best response to a gas influx • Matching the model with experimental and field data obtained from Wired Drill String Technology • Semi-annual Advisory Board Meeting (ABM) reports and the Final Report

Project Status and Proposed Time Table

Work Time Deliverables

2010 2011 2012 2013 Project Status

1-4 5-8 9-12 1-4 5-8 9-12 1-4 5-8 9-12 1-4 5-8

Literature Review 95% Mathematical Modeling 90% Computer Simulations 80% Field Data Analysis 60% Final Report 20%

Investigation of Cuttings Transport in 30-60 Degree

Inclined Wells

Feifei Zhang

Investigation of Cuttings Transport in 30~60 Degree Inclined Wells Investigator: Feifei Zhang, TUDRP

Problem Statement: The solid concentration in wellbore need to be estimated and controlled accurately during drilling process to keep high

ROP and avoid drilling problems like drill pipe stuck, lost circulation.

Cuttings in the wellbore may have important effects on the bottom hole pressure. To better control bottom hole

pressure, cuttings behavior in wellbore must be studied clearly.

Before tripping out, the wellbore must be cleaned efficiently. To estimate the minimum circulation time to clean the

wellbore, cuttings behavior in unsteady state need to be investigated.

Objectives: Conduct a series of cuttings transport experiments with different drilling fluids to study cuttings behavior at different

operational parameters.

Develop models to predict flow patterns, change of cuttings concentration and pressure drop with changes of given

drilling parameters. Study cuttings transient behavior, develop models for real-time cuttings and pressure monitoring in the whole well and

integrate the experimental and modeling results for practical applications.. Steady Cuttings Behavior:

Based on experimental observation, four solid-liquid flow patterns were proposed: constant bed flow, waved bed flow,

packed dune flow and dispersed dune flow. From experimental data, a solid-liquid, two-phase flow pattern map is

developed. Different mechanistic models are developed for each flow pattern to predict cuttings behavior and pressure

gradient in the wellbore.

Applications: Circulation before tripping may include three situations: 1. the flushing flow rate is large than the drilling flow rate; 2.

the flushing flow rate equals the drilling flow rate; 3. the flushing flow rate is smaller than the drilling flow rate.

The solid fraction and position in the well have significant effect on bottom hole pressure, real-time monitoring of

solids in the well have important applications in Managed Pressure Drilling.

Integration of the cuttings behavior in the whole well has important applications in well design and operation

parameter optimization.

Project Status:

Tasks 2012 2013 2014 8 10 12 2 4 6 8 10 12 2 4 6

Literature Review × × × × × 40%

Facility Rebuilding × × × × × 100%

Modeling × × × × × 20%

Experiment × × × × × 40%

Data Analysis × × × × × 20%

Final Report 80%

PDC Drillbit Modeling and Experiments

Babak Akbari

PDC Drill Bit Modeling and Experiments

Investigator: Babak Akbari

Sposnosr: TUDRP

Objectives: To conduct single PDC cutting tests while controlling the pore pressure (thereby, the differential pressure) To conduct single PDC cutting tests with different size of cutters To develop a single PDC cutter mechanistic model in 3D. The model will be based on theory as well as

experimental results The model will take into account details such as chamfer, as well as back and side rake angles To develop a numerical code for rock cutting, emphasizing on the effect of differential pressure

Work since Last ABM

Analyzed a previous data base on cutter back rake angle and was able to draw conclusions on the general behavior of the rock cutting frictional response and the effect of the back rake angle of the cutter

Proposed a new model to take into account details of a composite-faced (chamfered) cutter; the new model was assisted by analyzing the results of previous studies

Conducted a series of experiments with 450-psi confining pressure using two 13-mm diameter cutters. The cutters have 0.010” and 0.016” chamfer size; shallow depths of cut ranging from 0.003” to 0.030” were investigated.

Analyzed the data and tested a hypothesis that the cutter geometry plays a significant role in the normal-horizontal force plot of the data; the hypothesis was confirmed

Conducted a preliminary analysis on the grain size distribution of cuttings produced at different confining pressure conditions

Future Work

Will conduct a second set of experiments with chamfered cutters of size 13mm Will continue particle size analysis of the cuttings Will start developing a numerical code to investigate the effect of differential pressure Will do another set of experiments looking into the effect of differential pressure, resources permitting

Project Status 2011,9-12 2012,1-6 2012,7-12 2013,1-6 2013,7-12 2014,1-6 2014, 7-9

Literature Review

Pore Pressure Experiments

Mechanistic & Numerical Modeling

Cutter Size -- Experiments

Final Analysis/conclusion

Final Report

Effect of Free Drillstring Rotation on Frictional

Pressure Losses

Oney Erge

Effect of Free Drillstring Rotation on Frictional Pressure Losses

INVESTIGATOR: Oney Erge, TUDRP INTRODUCTION:

Keeping mud equivalent circulating density in the operating window between the pore and fracture pressure is a challenge. To overcome this challenge, accurate estimation of frictional pressure loss in the annulus is essential, especially for extended reach and slim hole drilling applications usually encountered in shale gas and/or oil drilling.

Field and experimental measurements show that pressure loss in the annulus is strongly affected by pipe rotation and the eccentricity.  In a wellbore, the drillstring rotates freely and as a result, eccentricity varies. There is a substantial need for a reliable model that accurately estimates the effect of free drillstring rotation on frictional pressure losses. FOCUS OF THE PROJECT:

Transition from laminar to turbulent flow of Yield Power Law (YPL) fluids in concentric and eccentric annuli Effect of drillstring eccentricity, buckling and rotation on frictional pressure losses of YPL fluids

OBJECTIVES:

To develop a mathematical model for the flow of YPL fluids in annuli including the effect of free drillstring rotation To develop a criterion for the transition from laminar to turbulent region in annular geometries To conduct experiments using Yield Power Law fluids in an annular geometry, including a freely rotating drillstring

PROGRESS:

In order to predict the transition from laminar and turbulent flow regions, the Ryan and Johnson Stability Criterion is modified for concentric and eccentric annuli

CFD analysis is conducted to evaluate the effect of eccentricity and the available models are compared A method for estimating pressure losses for the turbulent flow of YPL fluids in eccentric annuli is proposed A numerical model is proposed for the laminar and turbulent flow of Newtonian and non-Newtonian fluids in concentric annuli

including the effect of inner pipe rotation An experimental database is created for the annular flow of YPL fluids with a free drillstring and buckled configurations with

and without rotation New friction factors are proposed for free drillstring, sinusoidal, transitional and helically buckled drillstring with and without the

rotation A new hydraulic model set is proposed for the laminar, transitional and turbulent flow of YPL fluids in concentric, eccentric and

buckled geometries with and without rotation of the inner pipe Videos for each buckling and rotation cases are available

Project Status Transition Criterion Annular Frictional Pressure Loss

Estimation

Literature Review 100% 100% Experimental Facility Modification 100%

Experiments 80% Modeling 100% 90%

Final Report 90%

FUTURE WORK:

Finalize the experiments and modeling Complete the Final Report

Stress Path Analysis in Depleted Sands

Mojtaba Pordel Shahri

EXECUTIVE SUMMARY Stress Path Analysis in Depleted Sands

Investigator: Mojtaba Pordel Shahri, TUDRP

Problem Statement: There has been an increasing consciousness regarding to the stress changes associated with reservoir depletion as the industry

moves toward more challenging jobs in deep-water or depleted reservoirs. These stress changes have a significant impact on the

design of wells in these situations. Therefore, accurate prediction of reservoir stress path, i.e., change in horizontal stresses with

pore pressure, is of vital importance.

Objectives: • To develop an understanding of the theory of poroelasticity and reservoir stress path in partially depleted sands

• To develop a model for predicting reservoir stress path during production/injection in partially depleted reservoirs

• To develop a computer simulator for predicting the reservoir stress path

• To verify the model using field data

Current Works:

• An improved formulation of stress path is developed that enables us to predict the effect of pore pressure on both

minimum and maximum horizontal stresses in the presence of non-hydrostatic stress field for future well design

consideration.

• The Poisson’s ratio is usually obtained using well-logging, fracturing data and core samples which is representative of

only near wellbore region. In this research, we propose a technique by extending the currently used powerful pressure-

transient testing concepts to include the reservoir stresses. More specifically, the interference well test is generalized to

find the average dynamic in-situ Poisson’s ratio. Average in-situ value can be utilized in different applications such as

in-situ stress field determination, stress distribution and rock mass deformation, and next generation of coupled fluid

flow – geomechanical simulators.

• An analytical model is proposed for predicting reservoir stress changes at different times and locations within reservoir

during production history. The spatio-temporal stress path analytical model is obtained based on a fluid flow-

geomechanical model for a line-source production during the Pseudo-Steady-State period.

Deliverables: • Mathematical model for predicting reservoir stress path

• Computer simulator for predicting reservoir stress path

• Matching the proposed model with field data

• Semi-annual Advisory Board Meeting (ABM) reports and the Final Report

• PhD dissertation Current Project Status:

Time

Work 2011 2012 2013 2014 Fall Spring Summer Fall Spring Summer Fall Spring Summer

Literature Review Mathematical Modeling Computer Simulation Experimental & Field Data Analysis Final Report

Automatic Control of

Drawworks

Zhaoyang Wang

EXECUTIVE SUMMARY

Automatic Control of Drawworks Investigator: Zhaoyang Wang, TUDRP

Problem Statement: Automation in the drilling industry has been at a relatively low level compared to other industries, however, research

and development on automation solutions within the drilling community has increased significantly during the last decade.

Tripping procedure is one of the main parts of a drilling process. With increasingly complex wellbore geometries and narrow

geo-pressure windows, it is not easy for the driver to estimate accurately the real maneuvering limits of the drawworks during

tripping, especially under poor downhole conditions. Thus, an optimization tripping model is needed to obtain the minimum

tripping time while maintaining the wellbore pressure, strength of drillpipe and drawworks in good condition.

Theoretical Work: Dynamic pressure surge model (Lubinski and R. Mitchell) and dynamic loading of drillpipe model (Lubinski) have

been reviewed. Lubinski’s dynamic loading on drillpipe model and dynamic downhole pressure surge model have been rebuilt.

This has allowed dynamic downhole pressure surge and dynamic loading on drillpipe phenomena to be simulated. At the same

time, dynamic velocity, which is the velocity at the bottom of the drillstring, is different from the input velocity at surface. The

effect of tripping velocity profile; i.e., tripping velocity changes with time, on the hook load, downhole pressure changes and

drillstring dynamic velocity has been studied. A tripping model has been developed based on optimization theory.

Recent Progress: Dynamic loading of drillstring and dynamic wellbore pressures surge under different tripping velocity profiles are

simulated and analyzed. A mathematical optimization model is built. Through this model, a minimum tripping time can be

obtained while maintaining the wellbore pressure within the pressure window and the drillpipe in good condition. The approach

to solve this optimization model is developed and the corresponding program is written.

Future Work: The optimization program at this time is time consuming and does not make full use of the maximum allowable

loading and pressure values. The developed optimization approach can be modified and improved. A better algorithm should be

developed to achieve optimized tripping velocity profile for the whole tripping in and out procedure.

Project Status:

Activity/Time Fall 2011

Spring 2012

Summer 2012

Fall 2012

Spring 2013 Status

Literature Review × × × 95%

Modeling × × × × 95%

Analysis of the results × × × × 95%

Final Report × 95%

Rheology of Lightweight Drilling Fluids with

Microsphere Additives

Bahri Kutlu

Rheology of Lightweight Drilling Fluids with Microsphere Additives – Bahri Kutlu

Introduction During a conventional drilling operation of a vertical well, major parameters controlling the circulating bottomhole pressure are density and flowrate. Since flowrate is mostly selected based on hole cleaning needs, fluid Density management is the most practical method to avoid problems while drilling subnormal pressured and depleted zones. To be able to drill these mentioned formations, use of a lightweight drilling fluid is necessary. The primary objective of using lightweight drilling fluids is to reduce wellbore pressure in order to prevent potential downhole losses, formation damage or fracturing the formation. This project, aims to reduce circulating bottomhole pressure by using lightweight solid additives and to study on HPHT rheological properties and flow characteristics of this alternative incompressible lightweight drilling fluid.

Objectives

The goal of this project is to conduct a study to develop incompressible drilling fluids with specific gravities less than water without using air or any other gas phase. Purpose is to offer an alternative to existing lightweight drilling fluids to decrease circulating BHP. Hollow glass microspheres are used as density reduction material. Rheological properties and flow characteristics of fluids mixed with microspheres are evaluated at HPHT and dynamic conditions.

Scope of Work Rheological experiments are conducted under HPHT conditions using a Fann75 viscometer. Microspheres are exposed to as high as 18000 psi and 250 F for characterization and microsphere survival ratio analysis. Experiments under dynamic conditions are conducted using a flowloop for a wide range of shear rates covering laminar and turbulent regimes. Rheological characterization and hydraulic drag reduction analysis are conducted using data collected from three different base fluids.

Conclusions • Hollow microspheres reduce the density. Under high pressure, hollow microspheres averaged 93% survival ratio (Chapter 6.1.1). • Rheology of fluids mixed with microspheres is similar to rheology of conventional fluids, and can be estimated with a modified

version of Einstein’s viscosity model (Chapters: 6.2.2.2, 6.2.3.2, 6.2.4.2). • Investigation of rheology using different geometries yielded different results in the presence of microspheres (Chapter 6.3). • Drag reduction is observed in most of the experiments conducted with different base fluids and microsphere concentrations.

(Chapters: 6.2.2.3, 6.2.3.3, 6.2.4.3). • Hydraulics calculations showed reduction in circulating BHP and ECD values (Chapter 6.4). • Effect of microsphere concentration on temperature distribution of non-Newtonian fluids along the wellbore, bottomhole

temperature and mud return temperatures are investigated. For the fluid rheology and wellbore configuration considered, hollow microspheres have a slight impact on temperature distribution (Chapter 6.4).

Deliverables Experimental data obtained for a conventional drilling fluid containing glass microspheres under HPHT and flowloop conditions. The data obtained for rheological characterization and drag reduction analysis. Final Report is due for November 2013.

Time Table

2011 2012 2013 8-12 1-6 7-12 1-8 9-11

Literature Review ■

Facility design ■ ■

Exp. data acquisition

■ ■ ■

Test Data analysis

■ ■ ■ ■ Analytical work

■ ■ ■ ■

Final report

■

Study of Effectiveness of LCM Materials

Hao Zeng

Study of Effectiveness of LCM Materials

Investigator: Hao Zeng, TUDRP

Introduction: Lost circulation is one of the most common well control problems encountered in drilling, cementing and

completion operations. It will not only waste time and drilling fluid. It can also damage formations, lead to hole collapse,

stuck drill pipes and can even cause blowouts and well abandonment. Large amounts of time and money are spent to

control lost circulation. The use of lost circulation materials (LCM) is the most common method to treat lost circulation.

However, the use of LCM is poorly understood and has achieved no significant breakthroughs in the past 40 years. As a

result, maximizing the effectiveness of LCM is now most important to minimize the cost in lost circulation.

Objectives:

• Provide more thorough understanding of existing PSD selection theories and rheological issues that occur in

fractured wellbores.

• To observe LCM behavior in uniform sized fractures under different flow rate.

• To determine the effectiveness of different LCM materials.

• To develop an optimized LCM selection model.

Current Work:

• Went throw existing fracture size and pressure models, hydraulic ECD models and LCM selection models.

• Developed a primary model to evaluate LCM effectiveness.

• Modified Parallel Plates Radial Flow Facility in TUDRP.

• Designed and run a series of tests with Parallel Plates Radial Flow Facility.

• Analyzed the experimental data; verified existing methods and theories based on the experimental data; compared

test data with simulation data.

Deliverables:

• Advanced LCM effectiveness testing facility.

• Experimental observation and analytical analysis of LCM bridging behavior.

• Optimized LCM selection model.

• Semi-Annual Advisory Board Meeting (ABM) reports and the final report.

Project Status Fall Spring Summer Fall Spring Summer

Literature Review X X X X X

Experimental Technique Development X X X X Experiments X X X X Data Analysis X X X X

Modeling X Final Report X X

Comparison of Steel, Aluminum, Titanium and

Composite Drill Pipe

Mehran Mehrabi

EXECUTIVE SUMMARY Comparison of Steel, Aluminum, Titanium and Composite Drillpipe

Investigator: Mehran Mehrabi, TUDRP

Problem Statement:

The emergence of drill pipes made of materials other than steel needs a thorough study of advantages and disadvantages compared with

conventional drill pipes. To the best of the author’s knowledge there is no published literature on comparison of four different categories of drillpipes

(DP) that considers mechanical aspects in a single study. However, there are some scattered papers on comparison of a specific mechanical aspect in

a special drilling scenario for two or three categories of DPs.

Objectives:

The following aspects of drillpipe mechanics are going to be studied.

I. Fatigue performance

II. Buckling

III. Torque and drag loads

IV. Margin of overpull (MOP)

Scope of Work:

In this project the mechanical behavior of four different groups of drillpipes (SDP, ADP, TDP and CDP) will be studied and compared.

Specifically, the comparisons will include:

I. Fatigue performance in build-up and drop-off section both under tension and compression in a constant curvature dogleg

II. Buckling behavior in vertical, horizontal and inclined section of a well

III. Torque and drag loads based on soft and stiff drillstring modeling

IV. Margin of overpull

Recent Progress:

Resistance of SDP, ADP, and TDP to fatigue failure in constant curvature doglegs are compared. It is shown that a type of drillpipe that has a

better fatigue resistance than the other types in a given DLS may perform worse than others in a different DLS. It is also shown that generated

contact force at the tool joints of TDP could be very harmful to the casing wear and wellbore integrity. Large contact force at the pipe tube of ADP

can reduce its corrosion resistivity.

Deliverables:

I. A computer program for investigating and comparing:

a. Fatigue performance

b. Buckling

c. Torque and Drag

II. Drillstring design guidelines (including MOP)

III. Semi-annual Advisory Board Meeting (ABM) and the Final Report

IV. Master Thesis

Proposed Time Table:

Time

Work

2012 2013 2014

Fall Spring Summer Fall Spring Summer

Literature Review

Fatigue performance computer program

Buckling computer program

Torque and drag load computer program

Margin of overpull comparison

Final Report

Displacement and Mixing of Fluids in Pipe Flow

Sukru Durmaz

DISPLACEMENT AND MIXING OF FLUIDS IN PIPE FLOW

INVESTIGATOR: Sukru Durmaz INTRODUCTION: There are various applications related to displacement of fluids in the petroleum industry. For example, displacement of spots, displacement of sweeps, displacement of spacers, and displacement of cement slurries. Contamination can cause significant changes in both displacing and displaced fluid properties during displacement processes and these changes can lead to various serious problems in many applications. The primary objective of this project is to analyze the mixing of fluids in displacement processes and to observe the influence of these parameters on the mixing of fluids during displacement processes in pipe flow. OBJECTIVES:

• To develop better understanding of mixing of fluids flowing inside circular pipes and to observe the influence of various parameters (density and viscosity of fluids, pipe inclination, flow regime) during the displacement process.

• To develop a model for describing fluid displacement in circular pipes. • To obtain high quality experimental data using different fluids at different inclination angles during the displacement process. • Analyze the data and determine the influence of various parameters on mixing of fluids in pipe flow during the displacement process.

SCOPE OF WORK:

• Displacement and mixing of fluids flowing inside circular pipes will be investigated both theoretically and experimentally. • Water-based fluids with different rheological and physical properties, such as high and low viscosities, and high and low densities, will

be used as displacing and displaced fluids. • A model will be developed for describing the mixing and displacement process of fluids in circular pipes. Comparisons will be made

between the developed model and experimental results. RECENT PROGRESS:

• TUDRP’s Displacement and Mixing Facility (DMF) modifications are finalized. DMF gives an opportunity to test with different test section inclinations from horizontal to vertical. Also, it allows us to collect experiments both upward and downward displacement processes.

• Water tests with various flow rates and inclination angles are currently in progress. FUTURE WORK:

• Experimental data acquisition using different fluids at different inclination angles and flow rates during the displacement process. • Development of the model describing fluid displacement in circular pipes. • Comparing experimental data with the data obtained from the theoretical work.

DELIVERABLES:

• Experimental data including pressure drop, contaminated volume and digital images during displacement tests with various fluids at various inclination angles and flow rates

• A model describing the displacement process • Semi-annual ABM Progress Reports and a Final Report

TIMELINE:

8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6Literature Review Facility DesignEx. Data AcquationTest Data AnalysisTheoritical WorkFinal Report

2012 2013 2014

Review of Cuttings Transport

Reza Ettehadi Osgouei

EXECUTIVE SUMMARY Cuttings Transport Review Investigators: Reza Ettehadi Osgouei, The University of Tulsa, Drilling Research Projects

Introduction: Numerous experimental and theoretical studies dating back more than seven decades have been conducted by researchers in order to better understand the factors influencing cuttings removal from the wellbore. Consequently, empirical and semi-empirical correlations, and analytical models have been developed based on the experimental observations to characterize the carrying capacity of drilling fluids. In addition, many guidelines have been developed to improve hydraulic programs and to tackle challenges encountered during drilling operations. Although a growing number of research studies on cuttings transport have led to publication of some review articles during the past decades, a comprehensive and systematic review has not been reported. This portion of the review is concerned with the vertical section of a wellbore. Objectives: The basic purposes of this study are to:

• Highlight flaws in previous research • Outline gaps and weaknesses in previous research • Address conflicts in the research • Prevent duplication of effort • Point the way forward for further research

Scope of Work: The overall scope of this study is to evaluate completed research projects in TUDRP and technical papers related to cuttings transport. The focus of the present report will be on what is so far understood about the mechanisms controlling cuttings transport in wellbore, and how this knowledge can be applied to solving the prevailing drilling problems in the field.

Summary and Conclusions: • Extensive literature review has been done. • Summary of experimental parameters has been prepared. It consists of experimental data extracted from 98 technical

papers and 13 completed research projects at TUDRP. • A technical report has been prepared. The present report is an evaluative review of completed research

projects at TUDRP and studies found in the literature related to cuttings transport in the vertical section of a wellbore. It describes, summarizes, evaluates and clarifies the literature.

Deliverables: • Summary of extracted experimental data • Semi-Annual ABM Progress Report and a Final Report

Tentative Time Table:

Annular Pressure Build Up (APB) Analysis-Optimization

of Fluid Rheology

Reza Ettehadi Osgouei

EXECUTIVE SUMMARY Annular Pressure Build Up (APB) Analysis- Optimization of Fluid Rheology

Investigators: Reza Ettehadi Osgouei, The University of Tulsa, Drilling Research Projects

Introduction: Higher geothermal gradients of the formations in deeper sections of the wellbore and heat transfer from hot reservoir

fluid flowing in tubing during the production are two factors which elevate the temperature of the casings and annular fluids at the bottom of the annular space in the wellbore. Consequently, a temperature gradient between the surface and the bottom of annular space functions as the driving force for convective heat transfer during production. This will lead to secondary fluid flow within the annulus.

Objectives: • To develop a better insight of convective heat transfer in the annulus of casing • To model the convective heat transfer of Yield Power Law fluids across vertical parallel plates and to predict long time

behavior of annular fluids • To design experimental set up and to obtain high quality experimental data using different fluids • To design a guild line for selection of proper annular fluids for deep-water oil and gas wells to minimize the rate of

heat transfer from the flowing production fluid

Scope of Work: The proposed project includes both modeling and experimental work to understand convective heat transfer along the

annular space. This work can be done in two stages: • To develop a mathematical model for estimating the optimum properties of Yield Power Law fluids across vertical

parallel plates by solving governing equations and considering boundary conditions. • To conduct an experimental study in a small-scale flow loop for simulating real wellbore conditions using non-

Newtonian, water-based and oil-based fluids

Summary and Conclusions • Extensive literature review has been done. • Experimental setup has been designed and constructed. • Two analytical models have been formulated to model the steady state and the transient free convection between two

parallel plates. • In the case of Newtonian fluids, the results of model indicate that the magnitude of temperature gradient and gap

between parallel plates as well as viscosity of annular fluid have significant effects on the secondary flow velocity distribution.

Deliverables: • Experimental data, including pressure drop and temperature distribution, during APB (annular pressure buildup) tests

with various fluids • Mathematical model describing the convective heat transfer of Yield Power Law fluids • Semi-Annual ABM Progress Reports and a Final Report • Computer program

Tentative Time Table:

8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6

Literature review

Facility design

Exp. data acquisition

Test data analysis

Mathematical model

Final report

2012 2013 2014

The Effects of Nano-Particles on Foam Stability and Rheological Properties

Ziad Alabdullatif

The Effect of Nanoparticles in Foam Stability and Rheological Properties

INVESTIGATOR: Ziad Alabdullatif

STATEMENT OF THE PROBLEM: A very stable, economical, and environmentally friendly foam that can withstand high pressure, high temperature, and high concentration of contaminants is preferable for successful drilling operations. Foam is preferable due to its low need of water use, exceptional cuttings transport, low effective density for UBD, and unique curved pressure profile, due its compressibility, makes it suitable for deepwater applications. However, foam is a metastable system that becomes unstable and break in short time resulting in downhole pressure fluctuation. Introducing nanoparticles into the foam system proved to be a very effective way to stabilize foam. This dissertation objective is to investigate on the role of using different nanoparticles to generate Particles-Stabilized Foam (PSF). The rheology, pressure losses, and digital images of PSF need to be studied as well.

OBJECTIVES: To study the effect of different nanoparticles on the stabilization of Particles-Stabilized Foam (PSF). To investigate PSF rheology under elevated pressure and elevated temperature (EPET) using a rotational

viscometer and pipe viscometer. To investigate pressure losses of PSF under simulated underbalanced drilling conditions using a flow loop. To develop better understanding on the relation between foam rheology and stability as functions of bubble

size, shape and size distribution, and shear rate. To provide easy-to-use instructions for PSF generation for practical applications.

SCOPE OF WORK: Different nanoparticles with different concentration with different surfactants/agents will be tested to select the

optimum concentration of nanoparticles with the appropriate surfactant/agent to meet the requirement of downhole drilling applications. Half-life decay rate will be used to evaluate foam stability.

Test the rheology of PSF using rotational viscometer (Foam Generator/Viscometer, FGV) and pipe viscometer with drill pipe rotation (Advanced Cuttings Transport Facility, ACTF). The measurement on the ACTF will be compared with FGV to study the effect of dynamic flow with wall slip on the rheology of PSF.

Study the pressure losses under simulated downhole underbalanced drilling conditions for pipe and annular flow using the ACTF. This will be after determining the optimum nanoparticles with the appropriate surfactant/agent that can generate a PSF.

Images of PSF, obtained through a microscope, will be investigated for the relation between PSF, rheology and stability as a function of bubble size, shape and size distribution, and shear rate.

DELIVERABLES: Experimental data, including rheology, pressure losses, and digital images, for particles-stabilized foams

containing different nanoparticles. A software package for improved drilling foam hydraulics and a drilling simulator. Progress Reports and a Final Report

PRELIMINARY TIMELINE: