1-To calculate plastic viscosity of the mud .
2-To calculate yield point.
Viscometer or rheometer is a device used to measure the viscosity and yield point of mud, A sample of mud is placed in a slurry cup and rotation of a sleeve in the mud.
Skin factor is a dimensionless parameter that quantifies the formation damage around the wellbore. it also can be negative (which indicates improvement in flow) OR positive (which means formation damage exists). Positive skin can lead to severe well production issues and thus reducing the well revenue
1-To calculate plastic viscosity of the mud .
2-To calculate yield point.
Viscometer or rheometer is a device used to measure the viscosity and yield point of mud, A sample of mud is placed in a slurry cup and rotation of a sleeve in the mud.
Skin factor is a dimensionless parameter that quantifies the formation damage around the wellbore. it also can be negative (which indicates improvement in flow) OR positive (which means formation damage exists). Positive skin can lead to severe well production issues and thus reducing the well revenue
it is a benficial slide who wants to know about the drilling fluids and the rhelogical aspects of the drilling fluids. the things are clear and very clear in this slide and this slide is very beneficial for the one who know basics of drilling fluids in a knowledgeable way
Viscosity and yield point exp. by jarjis
Experiment Number 5: Yield Point.
Koya University.
Faculty of Engineering.
Drilling Lab
Supervised By Muhammad Jamal
Determine Plastic Viscosity, Apparent Viscosity, And Yield point of a drilling fluid (mud) by using Fann VG viscometer.
=============
This a report about Filtration. written by Jarjis Muhammad, Petroleum Engineering Dep. Koya University. For more Information please contact me: www.facebook.com/Jarjis.shaqlawaee
The fifth presentation of a series of presentations on Operations Geology. Very basic, just to introduce beginners to operations geology. I hope the end users will find this and the following presentations very helpful.
The objective of this test is to determine the bulk volume,
grain volume, pore volume and effective porosity of
interconnected pores of a core sample with the use of liquid
saturation method.
The presentation highlights the root causes of major drilling issues such as formation pressure uncertainty, subsurface feature like mud volcanoes, major fault, poor well planning & etc. Then it elaborates on consequences of all above on examples of wellbore instability, sticking, gumbo & so on.
Drilling engineering laboratory
The aim of the test is to know the ability of the mud to suspense the cutting during circulation stop by measuring the gel strength
Drilling fluids are absolutely essential during the drilling process and considered the primary well control.
Know more now about such a very important component of the drilling process.
it is a benficial slide who wants to know about the drilling fluids and the rhelogical aspects of the drilling fluids. the things are clear and very clear in this slide and this slide is very beneficial for the one who know basics of drilling fluids in a knowledgeable way
Viscosity and yield point exp. by jarjis
Experiment Number 5: Yield Point.
Koya University.
Faculty of Engineering.
Drilling Lab
Supervised By Muhammad Jamal
Determine Plastic Viscosity, Apparent Viscosity, And Yield point of a drilling fluid (mud) by using Fann VG viscometer.
=============
This a report about Filtration. written by Jarjis Muhammad, Petroleum Engineering Dep. Koya University. For more Information please contact me: www.facebook.com/Jarjis.shaqlawaee
The fifth presentation of a series of presentations on Operations Geology. Very basic, just to introduce beginners to operations geology. I hope the end users will find this and the following presentations very helpful.
The objective of this test is to determine the bulk volume,
grain volume, pore volume and effective porosity of
interconnected pores of a core sample with the use of liquid
saturation method.
The presentation highlights the root causes of major drilling issues such as formation pressure uncertainty, subsurface feature like mud volcanoes, major fault, poor well planning & etc. Then it elaborates on consequences of all above on examples of wellbore instability, sticking, gumbo & so on.
Drilling engineering laboratory
The aim of the test is to know the ability of the mud to suspense the cutting during circulation stop by measuring the gel strength
Drilling fluids are absolutely essential during the drilling process and considered the primary well control.
Know more now about such a very important component of the drilling process.
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
International Journal of Computational Engineering Research(IJCER)ijceronline
Β
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology
Rotameter calibration report for multiple fluidsSakib Shahriar
Β
We will study Rotameter and calibrate it for various fluids in this report. Mainly, we calibrated the rotameter for water. Calibration means nothing but the relationship between volumetric flow rate vs Rotameter reading.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Presentation given by Auli Niemi of Uppsala University on "PANACEA & TRUST Projects Status update" at the EC FP7 Projects: Leading the way in CCS implementation event, London, 14-15 April 2014
1. 1 | P a g e
DEPARTMENT OF CHEMICAL & PETROLEUM
MSc PETROLEUM ENGINEERING (3616)
EXPERIMENT 2 & 3
Rheology of Fluids & Hydraulic Calculations
&
Drilling Fluid (Mud) Filtration Tests
Team 8
Muhammad Kamal (3325610)
Ghazanfar Khan (3300082)
Adedamola Lawal (3330105)
Submitted To:
Mrs Maria Astrid Centeno
Submission Date:
20/02/2015
2. 2 | P a g e
Contents
Experiment No 2 β Rheology of Fluids & Hydraulic Calculations .....................................4
Summary................................................................................................................................4
Introduction.............................................................................................................................4
Objectives...............................................................................................................................5
Flow regimes.......................................................................................................................5
Viscosity..............................................................................................................................6
Shear stress........................................................................................................................6
Share rate ...........................................................................................................................7
Rheological models ............................................................................................................8
Circulating system ............................................................................................................10
Experimental Equipment......................................................................................................10
Procedure & Observation.....................................................................................................11
Experimental procedure ...................................................................................................11
Experimental observations...................................................................................................13
Results & Calculations .........................................................................................................13
Experimental calculations ....................................................................................................17
Calculations of sample Mud A: ............................................................................................17
Calculations of sample Mud B: ............................................................................................18
Calculations of sample Mud A: ............................................................................................20
Calculations of sample Mud B: ............................................................................................22
Mud A - Annulus...................................................................................................................24
Mud B - Annulus..................................................................................................................25
Experiment 3 β Drilling Fluid (Mud) Filtration Tests..........................................................26
Summary..............................................................................................................................26
Introduction...........................................................................................................................26
Experiment Equipment.........................................................................................................27
Background ..........................................................................................................................27
Potential problems from excessive filter-cake thickness .................................................27
Potential problems from excessive filtrate invasion .........................................................28
Filtration theory .................................................................................................................28
Static Filtration ..................................................................................................................28
Factors affecting filtration .................................................................................................28
Fluid-Loss control additives ..............................................................................................28
Polyanionic Cellulose (PAC) ............................................................................................28
3. 3 | P a g e
Experiment procedure and observations .........................................................................29
First phase procedure:......................................................................................................29
Second phase procedure: ................................................................................................29
Third phase procedure: ....................................................................................................30
Results & Calculations .........................................................................................................31
Discussion of Results...........................................................................................................33
Conclusions..........................................................................................................................34
References...........................................................................................................................34
4. 4 | P a g e
Experiment No 2 β Rheology ofFluids & Hydraulic Calculations
Summary
This experiment was carried out to investigate Rheology of fluids and hydraulic calculations. This
is important to the petroleum engineers in calculating friction loss in pipe or annulus, determination of
the equivalent circulating density of the drilling fluid, determination of the flow regime in the annulus,
determination of the rheological model, estimation of the hole cleaning efficiency and evaluation of the
fluid suspension capacity.
The objective of the experiment is to familiarize with the equipment used in laboratories and oil field to
design and adjust properties of drilling mud, application of rheological values or hydraulic calculations
and measurements of viscosity and rheological behaviour of drilling fluids by the use of viscometer
fann 35.
The key results obtained from the experiment done on two different samples given as mud A and mud
B are respectively, where for mud A PV = 10ππ,YP = 67 ππ 100ππ‘2β , n = 0.081 and K = 0.5871 and for
mud B PV = 10ππ,YP = 67 ππ 100ππ‘2β , n = 0.081 and K = 0.5871.
From the experiment we arrived at the conclusion that both mud A and mud B exhibit Herschel-
Bulkley model with shear stress plotted against shear rate and power low model with log-log shear
rate plotted against shear rate. The graphs plotted for apparent viscosity against shear rate for both
muds have very similar L-shape patterns. All this indicates that both muds exhibit similar rheology.
Introduction
Rheology and hydraulics are interrelated studies of fluid behaviour. Fluid rheology and hydraulics are
engineering terms that describe the behaviour of fluids in motion. Rheology is the science of
deformation and flow of matter. Primarily concerned with the relationship between shear stress and
shear rate and the impact they have on fluid flow characteristics inside tabular and annular spaces.
Hydraulic on the other hand deal with the mechanical properties of liquids, describing how fluid flow
creates and apply pressures. In drilling fluids, the flow behaviour of the fluid must be described using
rheological models and equations before the hydraulic equations can be applied. Rheology of fluids
and hydraulics are significant in petroleum industries during drilling operation to ensure the calculation
of frictional loss in pipe or annulus, determining the equivalent circulating density of the drilling fluid,
determining the flow regime in the annulus or pipe, estimating hole cleaning efficiency, evaluating fluid
suspension capacity, provide wellbore stability, provide energy at the bit to maximize Rate of
Penetration (ROP) and remove cuttings from the well.
5. 5 | P a g e
Objectives
ο· Familiarization with equipment used in laboratories and oilfield to design and adjust properties of
drilling mud.
ο· Measurements of viscosity and rheological behaviour of drilling fluids by using viscometer Fann
35.
ο· Application of rheological values in hydraulic calculations.
Flowregimes
The behaviour of a fluid is determined by the flow regime, which has a direct effect on the ability of
that fluid to perform its basic functions. The flow can either be laminar or turbulent, depending on the
velocity, size and shape of the flow channel, fluid density, and viscosity. Between laminar and
turbulent flow, the fluid will pass through a transition region where the flow of fluid has both laminar
and turbulent characteristics.
In laminar flow, the fluid moves parallel to the walls of the flow channel in smooth lines. Flow tends to
be laminar when the fluid is viscous. In laminar flow, the pressure required to move the fluid increases
with velocity and viscosity.
In turbulent flow, the fluid is swirling and eddying as it moves along the flow channel, even though the
bulk of the fluids move forward. These velocity fluctuations arise spontaneously. Wall roughness or
changes in flow direction will increase the amount of turbulence. Flow tends to be turbulent with
higher velocities or when the fluid has low viscosity. In turbulent flow, the pressure required to move
the fluid increases linearly with density and approximately with the square of velocity, meaning more
pump pressure is needed to move a fluid in turbulent flow than in laminar flow.
The transition between laminar and turbulent flow is controlled by the relative importance of viscous
forces in the flow. In laminar flow, the viscous forces dominate, while in turbulent flow the inertial
forces are more important. For Newtonian fluids, viscous forces vary linearly with the flow rate, while
the inertial forces vary as the square of the flow rate.
The ratio of inertial forces to viscous forces is the Reynolds number (Re). If consistent units are
chosen, the ratio will be dimensionless and the Reynolds number (Re) will be:
Re =
DVΟ
ΞΌ
Where:
D = diameter of the flow channel
V = average flow velocity
Ο = fluid density
ΞΌ = viscosity
The flow of any particular liquid in any particular flow channel can either be laminar, transitional, or
turbulent. The transition occurs at a critical velocity, for typical drilling fluids. Its normally occurs over a
range of velocities corresponding to Reynolds number between 2000 and 4000.
6. 6 | P a g e
Viscosity
Viscosity is defined as the ratio of shear stress to shear rate. The traditional units of viscosity are
dyne-sec/cm2
, which is termed poise. Since one poise represents a relatively high viscosity for most
fluids, the term centipoise (cp) is normally used. A centipoise equals one-hundredth of poise or one
millipascal-second.
ΞΌ=
Ο
Ξ³
Where:
ΞΌ = viscosity
Ο = shear stress
Ξ³ = shear rate
Viscosity value is not constant for most drilling fluids. It varies with shear rate. To check for rate
dependent effects, shear stress measurements are made at a number of shear rates. From these
measured data, rheological parameters can be calculated or can be plotted as viscosity versus shear
rate.
The term effective viscosity is used to describe the viscosity either measured or calculated at shear
rate corresponding to existing flow conditions in the wellbore or drill pipe. To be meaningful, a
viscosity measurement must always specify the shear rate.
Shearstress
Shear stress is the force required to sustain a particular rate of fluid flow and is measured as a force
per unit area. Shear stress Ο is expressed mathematically as:
Ο =
F
A
Where:
F = force
A = surface area subjected to stress
In a pipe, the shear stress at the pipe wall is expressed as:
Οw =
F
A
=
DP
4L
In an annulus with inner and outer diameters known, the shear stress is expressed the same manner
as:
Οw =
F
A
=
P(D2 β D1)
4L
Where:
D = diameter of pipe
D1= inner diameter of pipe
D2 = outer diameter of pipe
P = pressure on end of liquid column
7. 7 | P a g e
A = surface area of the fluid
L = length
Sharerate
Shear rate is a velocity gradient measured across the diameter of a pipe or annulus. It is the rate at
which one layer of fluid slide or move past another layer.
The velocity gradient is the rate of change of velocity (βV) with distance from the wall (h). Shear rate
is βV/h and have a unit of 1/time, the reciprocal of time usually in 1/sec. orsecβ1
. It is important to
express the above concept mathematically so that models and calculations can be developed. Shear
rate (Ξ³) is defined as:
Ξ³ =
dV
dr
Where:
dV = velocity change between fluid layers
dr = distance between fluid layers
Shear rate Ξ³wp at the wall can be expressed as a function of the average velocity (V) and the diameter
of pipe (D).
Ξ³wp= f(V, D) =
8VP
D
In which
VP=
Q
A
=
4Q
ΟD2
Where:
Q = volumetric flow rate
A = surface area of cross section
D = pipe diameter
V = velocity
VP = average velocity in pipe
In an annulus of outside diameter D2 and inside diameterD1, the wall shear rate can be shown as:
Ξ³wa= f(V, D1,D2
) =
12Va
D2βD1
In which
Va =
4Q
Ο(D2
2
βD1
2
)
Where:
Ξ³wp = shear rate at annulus wall
8. 8 | P a g e
V = velocity
Q = volumetric flow rate
D1 = inner annulus diameter
D2 = outer annulus diameter
Va= average velocity in annulus
Rheological models
The mathematical relationship between shear rate and shear stress is the rheological model of the
fluid. The concept of shear rate and shear stress apply to all fluid flow. Within a circulating system,
shear rate is dependent on the average velocity of the fluid in the geometry in which it flows.
Thus shear rates are higher in small geometries (drill string) and lower in large geometries (casing
and riser annuli). Higher shear rates usually cause a greater resistive force of shear stress. Therefore
shear stresses in drill string exceed those in annulus. The sum of pressure losses throughout the
circulating system (pump pressure) is often associated with shear stress while the pump rate is
associated with shear rate.
Fluids whose viscosity remains constant with change in shear rate are known as Newtonian fluids.
Non-Newtonian fluids are those fluids whose viscosity varies with change in shear rate. Those fluids
in which shear stress is directly proportional to shear rate are called Newtonian. Examples of
Newtonian are water, glycerine, and light oil.
Most drilling fluids are not Newtonian: the shear stress is not proportional to shear rate. Such fluids
are called non-Newtonian. Drilling fluids are shear thinning when they have less viscosity at higher
shear rates than at lower shear rates.
There are non-Newtonian fluids, which have dilatant behaviour. The viscosity of these fluids increases
with increasing shear rate. Dilatant behaviour of drilling fluids rarely, if ever occurs.
The distinction between Newtonian and non-Newtonian fluids is illustrated by using the API standard
concentric cylinder viscometer. If the 600-rpm dial reading is twice the 300-rpm reading, the fluid
exhibits Newtonian flow behaviour. If the 600-rpm reading is less than twice the 300-rpm reading, the
fluid is non-Newtonian and shears thinning.
One fluid type of shear thinning fluid will begin to flow as soon as shearing force or pressure,
regardless of how slight is applied, such fluids are known as pseudo plastic. Another type of shear
thinning fluid will not flow until a given shear stress is applied. This shear stress is called the yield
stress.
Fluids can also exhibit time dependent effects. Under constant shear rate, the viscosity decreases
with time until equilibrium is established. Thixotropic fluids experience a decrease in viscosity with
time while rheopectic fluids experience an increase in viscosity with time.
Most drill fluids are non-Newtonian, pseudo plastic fluids. Rheological models help predict fluid
behaviour across a wide range of shear rates. The most important rheological models that pertain to
drilling fluids are the:
Bingham model: is the most common rheological model used for drilling fluids. This model describes a
fluid in which the shear stress/shear rate ratio is linear once a specific shear stress has been
9. 9 | P a g e
exceeded. Two parameters, plastic viscosity and yield point are used to describe this model. Because
these constants are determined between the specified shear rates of 511 and 1022, this model
characterizes a fluid in the higher shear rate range.
Power Law: The power Law is used to describe the flow of shear thinning or pseudo plastic drilling
fluids. This model describes a fluid in which shear stress versus shear rate is a straight line when
plotted on a log-log graph. Since the constants, n and K from this model are determined from data at
any two speeds, it more closely represents an actual fluid over a wide range of shear rates.
Herschel-Buckley (Modified power law) model: The modified Power law is used to describe the flow of
a pseudo plastic drilling fluid, which requires a yield stress to flow. A graph of shear stress minus yield
stress versus shear rate is a stress line on log-log coordinates. This model has the advantages of the
Power Law and more nearly describes the flow of a drilling fluid since it also includes a yield value.
The rheological parameters recorded in an API drilling fluid report are plastic viscosity and yield point
from the Bingham Plastic Model, however for hydraulics calculations in important to have rheological
data shown on linear, semi-log or log-log graphs of shear rate versus shear stress or viscosity.
10. 10 | P a g e
Circulatingsystem
The circulating system of a drilling well is made up of a number of components or intervals, each with
a specific pressure drop. The sum of these interval pressure drops is equal to the total system
pressure loss or the measured standpipe pressure.
Experimental Equipment
Concentric cylinder viscometer
The equipment used was concentric cylinder viscometers, these viscometers are rotational
instruments powered by an electric motor or a hand crank. Fluid is contained in the annular space
11. 11 | P a g e
between two cylinders. The outer sleeves or rotor sleeve is driven at a constant velocity. The rotation
of the sleeve in the fluid produces a torque on the inner cylinder or bob with a torsion string restraining
the movement. This mechanism is illustrated in the figure below. In most cases, a dial attached to the
bob indicates the displacement of the bob.
When the rotor is rotating at a constant angular velocity w2 and the bob is held motionless (w1 = 0),
the torque applied by torsion spring to the bob must be equal but opposite in direction to the torque
applied to rotor by the motor. The torque is transmitted between the rotor and the bob by the viscous
drag between successive layers of fluid. If there is no slip at the rotor wall, the layer of fluid
immediately adjacent to the rotor also moving at an angular velocity w2. Successive layers of fluid
between r2 and r1 are moving at successively lower velocities. If no slip at the bob wall, the layer of
fluid immediately adjacent to the bob is motionless.
Overview of special features for the concentric cylinder viscometer
βThe Fann Model 35 Viscometer is widely known as the βStandard of the Industryβ for drilling fluid
viscosity measurements. The Model 35 Viscometer is a versatile instrument for research or production
use.
In the six-speed models, test speeds of 600, 300, 200, 100, 6 and 3 rpm are available via
synchronous motor driving through precision gearing. Any test speed can be selected without
stopping rotation. The shear stress is displayed continuously on the calibrated scale, so that
time-dependent viscosity characteristics can be observed as a function of time. The Model 35A
Viscometer is powered by a 60-Hz motor; Model 35SA Viscometer by a 50-Hz motor.
These instruments are equipped with factory installed R1 Rotor Sleeve, B1 Bob, F1 Torsion Spring,
and a stainless steel sample cup for testing specified by the American Petroleum Institute. Other
rotor-bob combinations and/or torsion springs can be substituted to extend the torque measuring
range or to increase the sensitivity of the torque measurement.
Shear stress is read directly from a calibrated scale. Plastic viscosity and yield point of a fluid can be
determined easily by making two simple subtractions from the observed data when the instrument is
used with the R1-B1 combination and the standard F1 torsion spring.β
Procedure & Observation
Experimental procedure
For the two different mud given as mud A and mud B respectively, the following procedure was taken:
12. 12 | P a g e
ο· Recently agitated sample was place in the cup and the surface of the mud adjusted to scribed line
on the rotor sleeve.
ο· The motor was started by placing the switch in the high-speed position with the gear shifted all the
way down. Waited for a steady indicator dial value, and recorded the 600-RPM reading. Gear was
changed only when motor was running.
ο· Switch changed to the low position with the gear shifted down, waited for a steady value and
recorded 300-RPM reading.
Switch changed to the high position with the gear shifted all the way up, waited for a steady value and
recorded 200-RPM reading.
Switch changed to the low position with the gear shifted all the way up, waited for a steady value and
recorded 100-RMP reading.
Switch changed to the high position with the gear shifted to the centre, waited for a steady value and
recorded 6-RPM reading.
Switch changed to the low position with the gear shifted to the centre, waited for a steady value to
recorded 3-RPM reading.
Densities of mud A and Mud B are 9.45lb galβ and 9.8lb galβ respectively as obtained from experiment
Mud A Mud B
RPM Reading (Ο΄) RPM Reading (Ο΄)
600 107 600 72
300 97 300 53
200 91 200 45
100 83 100 34
6 70 6 15
3 63 3 13
PV PV
YP YP
K K
n n
Table1. Experimental measurements.
13. 13 | P a g e
Experimental observations
Results & Calculations
Table of results/measurements obtain during laboratory session is as shown below:
Mud A Mud B
RPM Reading (Ο΄) RPM Reading (Ο΄)
600 107 600 72
300 97 300 53
200 91 200 45
100 83 100 34
6 70 6 15
3 63 3 13
PV PV
YP YP
K K
n n
Table2. Results/experimental measurements.
Table of all calculated results obtained during laboratory session is as shown below, with yield point
(YP) and shear stress (Ξ³) measured in pounds per 100 square feet (lb/100ft2
):
Mud A Mud B
RPM Reading
(Ο΄)
Shear
rate, Ξ³
Shear
Stress,Ο
Apparent
Viscosity
RPM Reading
(Ο΄)
Shear
rate, Ξ³
Shear
Stress,Ο
Apparent
Viscosity
600 107 1022 114.3 54 600 72 1022 76.9 36
300 97 511 103.5 97 300 53 511 56.6 53
200 91 341 97.2 137 200 45 341 48.1 68
14. 14 | P a g e
100 83 170 88.6 249 100 34 170 36.3 102
6 70 10.0 74.7 3500 6 15 10.0 16.0 750
3 63 5.0 67.3 6300 3 13 5.0 13.9 1300
PV 10 PV 19
YP 67 YP 33
K 0.5923 K 0.0887
n 0.0784 n 0.2743
Table3. Calculated experimental results.
Fig3. Shear stress vs shear rate for mud A
0
20
40
60
80
100
120
140
-500 0 500 1000 1500
Shearstress
Shear rate
shear stress vs shear rate
shear stress vs shear
rate
15. 15 | P a g e
Fig4. Log-log of Shear stress vs shear rate for mud A
Fig5. Apparent viscosity vs shear rate for mud A
0
0.5
1
1.5
2
2.5
0 2 4 6
Shearstress
Shear rate
log-log shear stress vs shear rate
log-log shear stress vs
shear rate
Linear (log-log shear
stress vs shear rate)
-1000
0
1000
2000
3000
4000
5000
6000
7000
-500 0 500 1000 1500
apparentviscosity
Shear rate
Apparent viscosity vs shear rate
apparent viscosity vs
shear rate
16. 16 | P a g e
Fig6. Shear stress vs shear rate for mud B
Fig7. Log-log of Shear stress vs shear rate for mud B
0
10
20
30
40
50
60
70
80
90
-500 0 500 1000 1500
Shearstress
Shear rate
Shear stress vs shear rate
Shear stress vs shear
rate
0
0.5
1
1.5
2
2.5
3
0 2 4 6
Shearstress
Shear rate
log-log of shear stress vs shear rate
log-log of shear stress
vs shear rate
Linear (log-log of shear
stress vs shear rate)
17. 17 | P a g e
Fig8. Apparent viscosity vs shear rate for mud B
Experimental calculations
Experimental sample calculations for each type of calculated results shown above in table 1 are
illustrated for mud A and mud B respectively below:
Calculations of sample Mud A:
Shear rate, Ξ³ (secβ1
) = 1.703Γ w; where w represent RPM.
Ξ³600 =1.703Γ600 = 1022sβ1
Ξ³300 =1.703Γ300 = 510sβ1
Ξ³200 =1.703Γ200 = 341sβ1
Ξ³100 =1.703Γ100 = 170sβ1
Ξ³6 =1.703Γ6 = 10sβ1
Ξ³3 =1.703Γ3 = 5sβ1
Shear stress, Ο (lb 100ft2β ) = 1.0678ΓΟ΄, where Ο΄ represent viscometer reading.
Ο600 = 1.0678Γ107 = 114 lb 100ft2β
Ο300 = 1.0678Γ97 = 104 lb 100ft2β
Ο200 = 1.0678Γ91 = 97 lb 100ft2β
Ο100 = 1.0678Γ83 = 89 lb 100ft2β
Ο6 = 1.0678Γ70 = 75 lb 100ft2β
Ο3 = 1.0678Γ63 = 67 lb 100ft2β
0
200
400
600
800
1000
1200
1400
0 20 40 60 80 100
Apparentviscosity
Shear rate
Apparent viscosity vs shear rate
Apparent viscosity vs
shearrate
18. 18 | P a g e
Plastic viscosity (PV)
PV = ΞΈ600 β ΞΈ300
PV = 107 β 97 = 10cp
Yield point (YP)
YP = ΞΈ300 β PV
YP = 97 β 10 = 67 lb 100ft2β
Rheological parameter K and n
n =
log
0.89
0.67
log
170
5
n = 0.081
K =
Ο2
Ξ³2
K =
0.89
(170)0.081
= 0.5871
Apparent viscosity, ΞΌa
ΞΌa= 300
Ο΄
w
ΞΌa= 300Γ
107
600
= 54
ΞΌa= 300Γ
97
300
= 97
ΞΌa= 300Γ
91
200
= 137
ΞΌa= 300Γ
83
100
= 249
ΞΌa= 300Γ
70
6
= 3500
ΞΌa= 300Γ
63
3
= 6300
Calculations of sample Mud B:
Shear rate, Ξ³ (secβ1
) = 1.703Γ w; where w represent RPM.
Ξ³600
=1.703Γ600 = 1022sβ1
Ξ³300
=1.703Γ300 = 510sβ1
Ξ³200
=1.703Γ200 = 341sβ1
21. 21 | P a g e
D2 = Pipe outside diameter = 5in =0.4167ft
D1 = Pipe outside diameter = 3.78 in = 0.3149ft
va =
0.408Γ0.5619
0.41672 β 0.31492
= 3.078ft secβ
fa =
16
Rea
or
a
(Rea)b
Where ππ π is the Reynolds Number.
Rea =
928va (D2 β D1 )Ο
ΞΌea
Where ΞΌea = effective viscosity in an annulus:
ΞΌea = 100Ka (
144 Va
D2βD1
)
(na β 1)
(
2na +1
3na
)
na
ΞΌea = 100Γ0.5871(
144Γ3.078
0.4167 β0.3149
)
(0.081 β 1)
(
2Γ0.081+1
3Γ0.081
)
0.081
ΞΌea = 0.03017cp
Then;
Rea =
928va (D2 β D1 )Ο
ΞΌea
Rea =
928 Γ 3.078(0.4167 β 0.3149)58.86
0.03017
Density of mud A = 9.45 lb galβ = 58.86lb ft3β
Rea = 567295.47
Since the Reynolds Number Rea > 2100, friction factor fa =
a
(Rea )b
Where a = (log na + 3.93)/50 = (log 0.081 + 3.93)/50 = 0.0568
b = (1.75 β log na
)/7 = (1.75 β log0.081)/7 = 0.4059
fa =
a
(Rea)b =
0.0568
(567295.47)0.4059 = 2.623Γ10β4
From the above values obtained the frictional loss pressure gradient,
Pa
Lm
is obtained
Pa
Lm
=
fa Γva
2
Γ Ο
25.51(D2βD1 )
Pa
Lm
=
2.623 Γ10β4
Γ3.0782
Γ 58.86
25.51(0.4167β0.3149)
= 0.05632 psi ftβ
Circulating pressure gradient,
ππ
π
22. 22 | P a g e
From calculations above
Ph
Lv
was calculated in lb galβ , so:
Ph
Lv
= 0.4914psi ftβ
Pc
L
=
Ph
Lv
+
Pa
Lm
= 0.4914+0.05632= 0.5477psi ftβ
Equivalent circulating density, π π
Οc=
19.625Pc
Lv
Οc = 19.625Γ0.5477 = 10.75lb galβ
Calculations of sample Mud B:
Circulating pressure gradient
Pc
L
is given as:
ππ
πΏ
=
πβ
πΏ π£
+
π π
πΏ π
Where,
πβ
πΏ π£
= Hydrostatic pressure gradient
π π
πΏ π
= frictional loss pressure gradient
πβ
πΏ π£
= 0.052Ο
Where Ο = density of Mud B:
πβ
πΏ π£
= 0.052Ο = 0.052Γ9.80 = 0.5096ππ π ππ‘β
Hydrostatic pressure gradient = 0.5096 ππ π ππ‘β
π π
πΏ π
=
ππ Γπ£ π Γ π
25.51(π·2 βπ·1 )
Where π£π = velocity in annulus =? and ππ = frictional factor in annulus=?
π π
πΏ π
=
ππ Γπ£ π
2
Γ π
25.51(π·2 βπ·1 )
π£π =
0.408π
π·2
2
β π·1
2
π = Flow rate = 210 ππ πππβ = 0.5619ππ‘3
π ππβ
π·2 = Pipe outside diameter = 5ππ = 0.4167ππ‘
π·1 = Pipe outside diameter = 3.78 ππ = 0.3149ππ‘
23. 23 | P a g e
π£π =
0.408Γ0.5619
0.41672 β 0.31492
= 3.078ππ‘ π ππβ
ππ =
16
π π π
or
π
(π π π) π
Where π π π is the Reynolds Number.
π π π =
928π£π (π·2 β π·1 )π
π ππ
Where π ππ = effective viscosity in an annulus:
π ππ = 100πΎπ (
144ππ
π·2 βπ·1
)
( π π β 1)
(
2π π +1
3π π
)
π π
π ππ = 100Γ0.091(
144Γ3.078
0.4167β0.3149
)
(0.2678 β 1)
(
2Γ0.2678+1
3Γ0.2678
)
0.2678
π ππ = 0.02344cp
Then;
π π π =
928π£π (π·2 β π·1 )π
π ππ
π π π =
928 Γ 3.078(0.4167 β 0.3149)61.04
0.02344
Density of mud B = 9.80ππ πππβ = 61.04ππ ππ‘3β
π π π = 17749.20
Since the Reynolds Number π π π > 2100, friction factor ππ =
π
(π π π) π
Where a = (log π π + 3.93)/50 = (log 0.091 + 3.93)/50 = 0.0578
b = (1.75 β log π π
)/7 = (1.75 β log0.091)/7 = 0.3987
ππ =
π
(π π π) π
=
0 .0578
(567295.47)0.3987
= 2.937Γ10β4
From the above values obtained the frictional loss pressure gradient,
π π
πΏ π
is obtained
π π
πΏ π
=
ππ Γπ£ π
2
Γ π
25.51(π·2 βπ·1 )
π π
πΏ π
=
2.937Γ10β4
Γ3.0782
Γ 61.04
25.51(0.4167β0.3149)
= 0.06540ππ π ππ‘β
Circulating pressure gradient,
ππ
πΏ
From calculations above
πβ
πΏ π£
was calculated in ππ πππβ , so:
24. 24 | P a g e
πβ
πΏ π£
= 0.5096ππ π ππ‘β
ππ
πΏ
=
πβ
πΏ π£
+
π π
πΏ π
= 0.5096+0.06540 = 0.5750ππ π ππ‘β
Equivalent circulating density, ππ
ππ =
19.625ππ
πΏ π£
ππ = 19.625Γ 0.5750 = 11.28ππ πππβ
The total friction loss pressure gradient in the pipe:
Drill pipe:
π π
πΏ π
Γ10,500= 0.05632 Γ10,500=591.87ππ π
Drill collar:
π π
πΏ π
Γ400= 0.05632Γ400=22.528 ππ π
Drill pipe + Drill collar = 591.87 + 22.528 = 614.398 ππ π
Mud A - Annulus
Drill pipe:
For 10500ft:
π π
πΏ π
Γ 10500= 0.05326Γ10500=559.23 ππ π
Drill collar:
For 400ft:
π π
πΏ π
Γ400=0.05632 Γ400=22.528 ππ π
Drill pipe (Annulus) + Drill collar (Annulus) = 559.23 +22.528 = 581.758 ππ π
Calculation of the Friction Loss in Bit Nozzles
ππ= 156 Γ π Γ π2 [(π·π1 2+ π·π2 2+β―) 2]
Therefore: ππ= 156 Γ 9.45 Γ 2102(11 2+ 11 2+ 12 2)2=443.261 ππ π
Calculation of the Standpipe Pressure for mud A
ππ π= β((πππ/πΏππ) Γ πΏππ)+ β((πππ/πΏππ) Γ πΏππ) + ππ
Therefore: ππ π= 581.758+ 614.398+443.261 =1639.417 ππ π
25. 25 | P a g e
Mud B - Annulus
Drill pipe:
π π
πΏ π
Γ10,500= 0.06540Γ10,500=686.7ππ π
Drill collar:
π π
πΏ π
Γ400= 0.06540Γ400=26.16 ππ π
Drill pipe + Drill collar = 686.7 + 26.16 = 712.86 ππ π
Drill pipe (Annulus) + Drill collar (Annulus) = 559.23 +22.528 = 581.758 ππ π
Calculation of the Friction Loss in Bit Nozzles
ππ= 156 Γ π Γ π2 [(π·π1 2+ π·π2 2+β―) 2]
Therefore: ππ= 156 Γ 9.8 Γ 2102(11 2+ 11 2+ 12 2)2= ππ π
Calculation of the Standpipe Pressure for mud A
ππ π= β((πππ/πΏππ) Γ πΏππ)+ β((πππ/πΏππ) Γ πΏππ) + ππ
Therefore: ππ π= 712.86+ 614.398+443.261 = 1770.52 ππ π
26. 26 | P a g e
Experiment 3 β Drilling Fluid (Mud) Filtration Tests
Summary
Experiment 3 is based upon drilling fluid filtration tests, which is quite significant to drilling
engineering. The objectives of this experiment have been listed as follows:
ο§ Understanding the mud filtration process and its applications in Drilling Engineering.
ο§ Evaluation of mud-cake building characteristics and effects of temperature and
pressure on mud filtrate behaviour.
ο§ Evaluation of the effects of polymer additive for fluid loss control properties.
ο§ Effects of mud filtrate in formation damage.
To carry out this experiment we used API Filter press and cell assembly equipment. This
experiment was carried out in three phases. First phase was based upon evaluating the
effects of differential pressure on mud filtrate and mud cake building characteristics and the
results are shown in the results and calculations section below. We observed loss of liquid
with respect to time under two different pressures respectively (100 psi and 400 psi). First
phase took an hour, 30 minutes for each pressure conditions.
The second phase was based upon the evaluation of effects of temperature on mud filtrate
and mud cake characteristics. This phase took 30 minutes and the readings were noted down
with respect to time and increasing temperature.
The third phase was based upon investigation on the effects of polymer additive to control
filtration. This phase had further two parts, which were based upon quantities of additive
added to the drilling fluid. 1g and 2g respectively were added in the drilling fluid and readings
noted down. Due to lack of time we carried out this experiment with 1g of additive and we
were instructed to obtain the reading of 2g additive part from another group and share our
readings with them. This phase was completed in 30 minutes and the readings were taken
with respect to time of the volume of fluid loss. At the end of each phase mud cakes were
observed and their thickness and diameters were measure with the digital Vernier calliper.
In this experiment we learned about the effects of temperature and pressure on drilling fluid
with and without additive respectively with respect to fluid loss and evaluation of their
respective mud cakes.
Introduction
The main function of the drilling fluid is to control the fluid loss, so measurements of the fluid
loss and mud cake evaluation is of utmost importance.
The objectives of this experiment have been listed as follows:
ο§ Understanding the mud filtration process and its applications in Drilling Engineering.
ο§ Evaluation of mud-cake building characteristics and effects of temperature and
pressure on mud filtrate behaviour.
ο§ Evaluation of the effects of polymer additive for fluid loss control properties.
ο§ Effects of mud filtrate in formation damage.
27. 27 | P a g e
Experiment Equipment
Background
Experiment 3 was basically conducted to show the importance of drilling mud and its
significance in Drilling Engineering. In general drilling fluid is used to seal permeable
formations and also to control the fluid loss that is filtration. After careful calculation and study
the mud is prepared which depends on the formations under interest. These tests are
performed on both low temperature and pressure & high temperature and pressure (HPHT).
There are numbers of potential problems associated with thick filter cake and excessive
filtration which includes tight holes, enlarged torque and drag values, drilling pipe trapped, lost
circulations, deprived log quality and formation damage.
Potential problemsfromexcessivefilter-cakethickness
High cake permeability's results in thick filter cakes, which reduce the effective torque when
rotating the pipe, excessive drag when pulling it. Thick cakes may cause the drill pipe to stick
28. 28 | P a g e
by a mechanism known as deferential sticking. There are two types of filtration involved in
drilling an oil well which are static filtration and dynamic filtration.
Potential problemsfromexcessivefiltrateinvasion
Excessive filtration invasion includes formation damage due to filtrate and solids invasion and
invalid formation fluid sampling test.
Filtrationtheory
For filtration to occur, the following three conditions are required:
A liquid or a liquid/solid slurry fluid must be present.
A permeable medium must be present.
The fluid must be at a higher pressure than the permeable medium.
Static Filtration
Static filtration is related to the fact when mud is not circulating. There are many factors
controlling under this condition but the main one to consider is the Darcy's law which is
related to flow of fluids through a permeable materials/formations (sandstone, sand or mud
filtrate).
Q = (k A ΞP) / ΞΌh
Factorsaffectingfiltration
Factors affecting filtration includes:
Time
Pressure differential filter cake compressibility
Filter cake permeability
Viscosity
Fluid-Losscontrol additives
There are several types of filtration control additives that are in practice, which depend upon
the mud system and its chemistry for example:
Clays
Polymers
PolyanionicCellulose(PAC)
29. 29 | P a g e
Polyaninic Cellulose which is non-ionic cellulose has high properties of purity, high DS, high
to low ranges of viscosity. It helps flow any solids present in the system and improves wall
mud cake characteristics. PAC is also very useful as it lowers the chance for stuck pipe.
Experimentprocedureandobservations
First of all we wore our PPE (Personal Protective Equipment) keeping in mind the H&S
procedures. After that we were given an initial demonstration by the technician and the
procedure is listed below. This experiment was carried out in three phases respectively and
same procedure was used to carry out three phases except the experimental conditions.
First phaseprocedure:
ο· Loose the T-screw at the top until the filter cell can be detached.
ο· Remove the filter cell and dissemble it, taking precautions.
ο· Make sure all parts of the filter cell are clean & dry.
ο· Check that the filtrate tube in the base cap is free of obstruction.
ο· Place the filter paper on top of the screen.
ο· Place the second rubber on top of the filter paper.
ο· Replace the cell body.
ο· Rotate the cell body according to the arrow head given until itβs fully fastened itself into the J-
Slot.
ο· Now fill the filter cell with the mud sample and make sure to leave some space/gap in the cell
as the fluid expands under pressure & temperature.
ο· Place the mud filled cell body into the equipment.
ο· Make sure to correctly tighten the T-screw.
ο· Place a graduated cylinder under the filtrate tube.
ο· Rotate the pressure relief valve & the regulator valve until you get the desired pressure value
in, first of all 100 psi and then 400psi.
ο· Let each experiment of the first phase test run for 30 minutes & take the required reading for
the experiment after every 5 minutes.(Stop watch used)
ο· Now open the cell body according to the opening instructions on the equipment.
ο· Also open the pressure relief valve by moving it in the vertical direction.
ο· Wait for some time so that the pressure is fully released.
ο· Remove the cell by loosening the T-screw.
ο· Open the top cap & take the mud out and also remove the bottom cap.
ο· To take out the filter paper by moving the bottom cap in the upside down direction.
ο· Inspect the filter paper for the physical properties and measurement of the thickness and
diameter of the mud cake with the help of Vernier calliper.
ο· Clean & dry all parts of the equipment.
Secondphaseprocedure:
ο· Loose the T-screw at the top until the filter cell can be detached.
30. 30 | P a g e
ο· Remove the filter cell and dissemble it, taking precautions.
ο· Make sure all parts of the filter cell are clean & dry.
ο· Check that the filtrate tube in the base cap is free of obstruction.
ο· Place the filter paper on top of the screen.
ο· Place the second rubber on top of the filter paper.
ο· Replace the cell body.
ο· Rotate the cell body according to the arrow head given until itβs fully fastened itself into the J-
Slot.
ο· Now fill the filter cell with the mud sample and make sure to leave some space/gap in the cell
as the fluid expands under pressure & temperature.
ο· Place the mud filled cell body into the equipment.
ο· Make sure to correctly tighten the T-screw.
ο· Place a graduated cylinder under the filtrate tube.
ο· Increasing temperature at 400 psi, water loss form the drilling mud was observed.
ο· Let each experiment of the first phase test run for 30 minutes & take the required reading for
the experiment after every 5 minutes.(Stop watch used)
ο· Now open the cell body according to the opening instructions on the equipment.
ο· Also open the pressure relief valve by moving it in the vertical direction.
ο· Wait for some time so that the pressure is fully released.
ο· Remove the cell by loosening the T-screw.
ο· Open the top cap & take the mud out and also remove the bottom cap.
ο· To take out the filter paper by moving the bottom cap in the upside down direction.
ο· Inspect the filter paper for the physical properties and measurement of the thickness and
diameter of the mud cake with the help of Vernier calliper.
ο· Clean & dry all parts of the equipment.
Thirdphaseprocedure:
ο· Loose the T-screw at the top until the filter cell can be detached.
ο· Remove the filter cell and dissemble it, taking precautions.
ο· Make sure all parts of the filter cell are clean & dry.
ο· Check that the filtrate tube in the base cap is free of obstruction.
ο· Place the filter paper on top of the screen.
ο· Place the second rubber on top of the filter paper.
ο· Replace the cell body.
ο· Rotate the cell body according to the arrow head given until itβs fully fastened itself into the J-
Slot.
ο· Now fill the filter cell with the mud sample and make sure to leave some space/gap in the cell
as the fluid expands under pressure & temperature.
ο· Place the mud filled cell body into the equipment.
ο· Make sure to correctly tighten the T-screw.
ο· Place a graduated cylinder under the filtrate tube.
ο· An additive was added the drilling mud, firstly 1g and then 2g. Water loss was observed in
both cases. We carried out the 1g additive sample and 2g sample values were shared from
another group.
ο· Let each experiment of the first phase test run for 30 minutes & take the required reading for
the experiment after every 5 minutes.(Stop watch used)
ο· Now open the cell body according to the opening instructions on the equipment.
ο· Also open the pressure relief valve by moving it in the vertical direction.
31. 31 | P a g e
ο· Wait for some time so that the pressure is fully released.
ο· Remove the cell by loosening the T-screw.
ο· Open the top cap & take the mud out and also remove the bottom cap.
ο· To take out the filter paper by moving the bottom cap in the upside down direction.
ο· Inspect the filter paper for the physical properties and measurement of the thickness and
diameter of the mud cake with the help of Vernier calliper.
ο· Clean & dry all parts of the equipment.
Results & Calculations
The effects of pressure on mud filtrate behaviour and mud cake building characteristics of
drilling fluids were taken into consideration. In this part we evaluate the effect of the
differential pressure on the fluid loss and mud cake thickness of a water based drilling fluid.
For this we prepared a drilling fluid by mixing 120 grs of bentonite in 2 litres of water. The
value for initial pressure was 400 psi and then reduced slightly to 350 psi.
100 PSI (Room Temp) 400 PSI (Room Temp)
Time (min) Volume (ml) Time (min)
Volume
(ml)
Initial (spurt lost)
5 5.5 5 8
10 8.5 10 12
15 10.5 15 15
20 12.2 20 17.4
25 13.86 25 21
30 15.25 30 22
Mud Cake Thickness (mm)
2.31
Mud Cake Thickness
(mm) 2.45
Mud Cake Diameter (mm) 77.36 Mud Cake Diameter (mm) 59.52
Table 1
0
5
10
15
20
0 1 2 3 4 5 6
Volume(ml)
time (sec)
100 psi
32. 32 | P a g e
Bentonite + Water 19Β° C (From Exp-1
400psi) Bentonite + Water 60Β° C
Time (min) Volume (ml) Time (min) Volume (ml)
Initial (spurt lost)
5 5.5 5 6.9
10 8.5 10 9.1
15 10.5 15 10.9
20 12.2 20 12.45
25 13.8 25 14.6
30 15.25 30 15
Table 2
0
5
10
15
20
25
0 1 2 3 4 5 6
Volume(ml)
time (sec)
400 psi
0
5
10
15
20
0 2 4 6
Volume(ml)
time (sec)
Bentonite + Water 19Β° C (From Exp-1
400psi)
Bentonite + Water 19Β°
C (From Exp-1 400psi)
33. 33 | P a g e
Effect of the temperature on mud filtrate and mud cake characteristics of a drilling fluid
formation.
Bentonite + Water 19Β° C (From Exp-1
400psi) Bentonite + Water 60Β° C
Time (min) Volume (ml)
Time
(min)
Volume
(ml)
Temperature
Β°C
Pressure
(psi)
Initial (spurt lost)
5 5.5 5 6.9 44.2Β°C 400
10 8.5 10 9.1 45.8Β°C 400
15 10.5 15 10.9 46.8Β°C 400
20 12.2 20 12.45 47.2Β°C 400
25 13.8 25 14.6 47.6Β°C 400
30 15.25 30 15 47.8Β°C 400
Table 3
Discussion of Results
The results show that with increase in pressure, more water loss has been seen (Table 1).
There was no much in water loss when the temperature was increased from 19C to 60C
(Table 2).
At an increasing temperature, at 400 psi, there was no much change noticed in terms of water
loss as shown in Table 3.
0
2
4
6
8
10
12
14
16
0 2 4 6
Volume(ml)
time (sec)
Bentonite + Water 60Β° C
Bentonite + Water 60Β°
C
34. 34 | P a g e
Conclusions
Experiment 2 and 3 carried out in the lab proved to be very helpful, as it provided us an opportunity to
experience the practical aspects of the theory.
From the experiment 2 we arrived at the conclusion that both mud A and mud B exhibit Herschel-
Bulkley model with shear stress plotted against shear rate and power low model with log-log shear
rate plotted against shear rate. The graphs plotted for apparent viscosity against shear rate for both
muds have very similar L-shape patterns. All this indicates that both muds exhibit similar rheology.
In experiment 3, we learned about the water loss from the drilling mud at various pressures and
temperatures as shown above through graphs and tables (readings noted down from experiments).
References
A.T Bourgoyne Jr, K.K. Millheim, M.E. Chenevert & F.S. Young Jr. (1986) βApplied Drilling
Engineeringβ, SPE Textbook Series Vol. 2, Chapter 2.
Fann (1995) Series 300 API Filter Press Instruction manual, (1995)
ISO 10414:2001 (Modified) (2003), βRecommended Practice for Field Testing Water-based Drilling
Fluids. API Recommended Practice 13 B-1 Third Edition.
Model 35 Viscometer. Instruction Manual . 2015. . [ONLINE] Available
at:http://www.fann.com/public1/pubsdata/Manuals/Model%2035%20Viscometer.pdf. [Accessed 17
February 2015].
OFITE (2009) HTHP Filter Press Instruction Manual, Ver. 2.0, 5/28/2009