Q922+de2+l05 v1
-
Upload
hossein-alaminia -
Category
Education
-
view
83 -
download
5
description
Transcript of Q922+de2+l05 v1
![Page 1: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/1.jpg)
Drilling Engineering 2 Course (2nd Ed.)
![Page 2: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/2.jpg)
1. drilling hydraulics: A. types & criteria of fluid flow
B. fluid Rheology and modelsa. Bingham plastic & Power-law models
![Page 3: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/3.jpg)
1. Laminar Flow in Pipes and Annuli
2. Turbulent Flow in Pipes and Annuli
3. Pressure Drop Across Surface Connections
4. Pressure Drop Across Bit
5. Optimization of Bit Hydraulics
6. Particle Slip Velocity
![Page 4: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/4.jpg)
![Page 5: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/5.jpg)
laminar flowing pattern application
For drilling operations the fluid flow of mud and
cement slurries are most important.
When laminar flowing pattern occurs, the following set of equations can be applied
to calculate the friction pressure drop [psi] Δp, the shear rate at the pipe wall 𝛾𝑤and the circulation bottom hole pressure for the different flow models:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 5
![Page 6: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/6.jpg)
Laminar: Newtonian Fluid modelFlow through pipe:
Flow through annulus:
When comparing the mean velocity υ with the so called “critical velocity”, denoted by υc (υcan, υcp),
the fluid flow pattern can also be determined. This classification is given by:
υ < υc ... laminar flowυ > υc ... turbulent flow
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 6
![Page 7: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/7.jpg)
Laminar: Bingham Plastic Fluid ModelFlow through pipe
υcp in [ft/sec]
Flow through annulus
υcan in [ft/sec]:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 7
![Page 8: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/8.jpg)
Laminar: Power-law Fluid ModelFlow through pipe
υcp in [ft/min]:
Flow through annulus
υcan in [ft/min]:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 8
![Page 9: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/9.jpg)
![Page 10: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/10.jpg)
turbulent fluid flow behavior description To describe the flow behaviour,
friction pressure loss and shear rate at the pipe wall for laminar flow, analytic equations are applied.
For turbulent fluid flow behavior, analytic models to calculate these parameters are extremely difficult to derive. Therefore, various concepts that
describe their behavior are used in the industry.The concept based on the dimensionless quantity
called “Friction factor” is the most widely applied correlation technique.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 10
![Page 11: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/11.jpg)
friction factor determination for fully developed turbulent flow pattern
𝜖 [in] ... absolute roughness of pipe, see from following table (Absolute pipe roughness for several types of circular pipes)
𝜖
𝑑[1] ... relative roughness of pipe
To solve this equation for f, iteration techniques have to be applied.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 11
![Page 12: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/12.jpg)
Friction factor for turbulent flow
The friction factor can also be obtained from the figure.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 12
![Page 13: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/13.jpg)
Friction factor estimation
In drilling operations, the relative roughness is oft assumed to be insignificant (usually less than 0.0004) which reduces the friction factor equation to the following equation for smooth pipes:
For smooth pipes and turbulent flow (𝜖
𝑑= 0 and 2,100 <= NRe <= 100,000),
the friction factor can be estimated by:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 13
![Page 14: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/14.jpg)
The pressure drop calculation at turbulent flow patternThe pressure drop at turbulent flow pattern is then
computed for the different flow models when replacing di with the equivalent diameter de = 0.816 (d2 − d1).
When the friction factor is computed, the pressure drops for the individual flow models can be calculated.
For Newtonian Fluid Model:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 14
![Page 15: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/15.jpg)
Power-law Fluid Model:
For fluids that behave according to the power-law fluid model, an empirical friction factor correlation based on the flow behaviour index n is used.
This correlation gives for:Flow through pipe:
Flow through annulus:
μa [cp] ... apparent Newtonian viscosity
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 15
![Page 16: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/16.jpg)
Friction factor for Power-Law
Reynolds number is then compared with the critical Reynolds number, which is depended on the flow behaviour index n and should be obtained from the figure
Friction factor for Power-Law fluid modelSpring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 16
![Page 17: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/17.jpg)
pressure drop for power law
Instead of using the figure, following equation can be applied to determine the friction factor iteratively:
When the friction factor f is calculated, the corresponding pressure drop can be calculated with the Newtonian fluid model equation:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 17
![Page 18: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/18.jpg)
![Page 19: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/19.jpg)
the total pressure loss at the surface equipmentThe pressure drop in surface connections comprise
the pressure drops along the standpipe, the rotary hose, swivel and kelly.
Since different rigs do use different equipment, the total pressure loss at the surface equipment can only be estimated. (Δpf )se [psi] ... pressure loss through total surface
equipment, q [gpm] ... flow rate, E [1] ... constant depending on the type of surface equipment used
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 19
Groups of surface equipment
![Page 20: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/20.jpg)
Equivalent drillpipe lengths for surface equipmentAnother approach is
to determine the equivalent length of drillpipe for each surface equipment and
then use the relevant equations to determine the surface pressure loss.
The Figure gives the equivalent lengths of the different equipment parts.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 20
![Page 21: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/21.jpg)
![Page 22: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/22.jpg)
![Page 23: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/23.jpg)
pressure drop across the bit
The pressure drop across the bit is mainly due to the change of fluid velocities in the nozzles.
To increase the penetration rate, when the mud flows through the nozzles its speed is increased drastically which causes a high impact force when the mud hits the bottom of the hole. This high fluid speed on the other hand
causes a relative high pressure loss.
This pressure loss is very sensitive to the nozzle seize.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 23
![Page 24: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/24.jpg)
Calculation of pressure drop across the bitThe bit pressure drop
itself can be calculated with:
AT [in2] ... total nozzle area
dn [1/32] ... jet nozzle seize
𝜐𝑛[ft/sec] ... mean nozzle velocity
q [gpm] ... flow rate
ρm [ppg] ... mud density
Cd [1] ... discharge coefficient, depending on the nozzle type and size (commonly Cd = 0.95)
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 24
![Page 25: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/25.jpg)
Initiating Circulation
All the equations to calculate the individual pressure drops presented above assume a nonthixotropic behavior of the mud.
In reality, an additional pressure drop is observed when circulation is started due to the thixotropic structures which have to be broken down.
This initial phase of addition pressure drop may last for one full circulation cycle.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 25
![Page 26: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/26.jpg)
Initiating Circulation pressure drop calculationThe additional pressure drop can be estimated
applying the gel strength τg of the drilling mud as:For flow through pipes:
For flow through annuli:
τg [lbf/100 ft2] ... gel strength of the drilling mud
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 26
![Page 27: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/27.jpg)
![Page 28: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/28.jpg)
hydraulic program design
The penetration rate in many formations is roughly proportional to the hydraulic horsepower expended at the bit.
To drill most efficiently hydraulic programs are designed for maximum bottom hole cleaning
(how much bottom hole cleaning is necessary to reach maximum penetration rate)
combined with maximum bottom hole cleaning based on the surface hydraulic horsepower availability.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 28
![Page 29: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/29.jpg)
drilling optimization parameters
For this reason, mud rheology,
hydraulics (individual pressure drops) and
bit nozzle selection are the parameters to consider for drilling optimization.
To optimize drilling hydraulics, different approaches can be made. The hydraulics can be designed to either optimize the nozzle velocity,
the bit hydraulic horsepower or
to optimize the jet impact force.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 29
![Page 30: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/30.jpg)
The total pressure drop at the circulation systemThe total pressure drop at the circulation system
is the summation of the pressure drop at the bit and
the pressure drop through the rest of the circulation system.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 30
![Page 31: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/31.jpg)
Optimum pressure drop across the bit
The pressure drop across the bit can be written as:
Hydraulic horsepower:
Jet impact force:
m [1] slope of the parasitic pressure loss (Δpf )d vs. flow rate
Theoretically m = 1.75
but in general it is better to determine m from field data than assuming this value.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 31
![Page 32: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/32.jpg)
optimum nozzle area
When plotting flow rate vs. pressure on a log-log plot, the optimum design is found at the intersection between the path of optimum hydraulics and the (Δpf )d line for either of the criteria mentioned above.
Having determined the optimum design, the optimum pump flow rate,
optimum nozzle area and
corresponding pressure losses can be calculated:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 32
![Page 33: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/33.jpg)
Optimum hydraulic horsepower and jet impact forceOptimum hydraulic horsepower and
jet impact force are given with:
The optimum nozzle area leads to the respective nozzle selection. Nozzles for drilling bits are given 1/32 [in] seizes thus the
calculated nozzle area has to be converted into n/32 [in].
Knowing n (has to be an integer and is commonly rounded down to ensure the nozzle velocity) and the amount of nozzles to use, the individual seizes are found.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 33
![Page 34: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/34.jpg)
specific hydraulic horsepower
The so called “specific hydraulic horsepower” is defined as hydraulic horsepower per unit borehole cross-section.
The optimization as discussed above is performed for regular intervals (e.g. 1,000 [ft]) and
is included in the drilling program.
In practice, computer programs are available in the industry that perform these hydraulic optimization calculations.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 34
![Page 35: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/35.jpg)
![Page 36: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/36.jpg)
The annular flow of the drilling fluid
The annular flow of the drilling fluid (carrying drilling cuttings and a certain amount of gas to the surface,)is disturbed by frictional and centrifugal forces
caused by the rotation of the drillstring.
In practice, when it is noticed that inefficient hole cleaning is present, either the mud flow rate is increased or the effective viscosity of the mud is increased or both adjustments are performed.
To estimate the slip velocity of the cuttings, following correlation methods were developed empirically
and are widely accepted and used in the industry:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 36
![Page 37: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/37.jpg)
Estimation of the slip velocity;Moore’s CorrelationMoore’s Correlation:
for NRp > 300:
for NRp < 3:
for 3 NRp < 300:
μa [cp] apparent Newtonian viscosity
ds [in] drilling cuttings diameter
NRp [1] particle Reynolds number
𝜐𝑠𝑙 [ft/sec] particle slip velocity
ρs [ppg] cuttings density
τg [lbf/100 ft2] gel strength required to suspend a particle of diameter ds
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 37
![Page 38: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/38.jpg)
Estimation of the slip velocity;Chien’s CorrelationChien’s Correlation:
The correlation equations determined by Chien are similar to the ones defined by Moore.
For clay-water muds, he recommends the usage of the apparent viscosity.
The correlation is performed as:
for NRp < 100:
for NRp > 100:
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 38
![Page 39: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/39.jpg)
transportation velocity
The so called “transportation velocity” 𝜐𝑇is defined as
the difference between the mean annular velocity 𝜐𝑎𝑛 and
the slip velocity 𝜐𝑠𝑙. The “transportation ratio” FT given by:
determines whether the cuttings are transported to the surface (FT is positive) or not and provides a relative measure of the carrying capability of the drilling mud.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 39
![Page 40: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/40.jpg)
minimum mean annular velocity
To have proper hole cleaning and with the knowledge of the transport velocity, a minimum mean annular velocity can be determined.
This minimum mean annular velocity has to be calculated at the annulus with the maximum cross-section area and in this way determines the minimum pump rate.
As a rule of thumb,
• a minimum mean annular velocity of 3 [ft/sec] is often applied.
Spring14 H. AlamiNia Drilling Engineering 2 Course (2nd Ed.) 40
![Page 41: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/41.jpg)
1. Dipl.-Ing. Wolfgang F. Prassl. “Drilling Engineering.” Master of Petroleum Engineering. Curtin University of Technology, 2001. Chapter 4
![Page 42: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/42.jpg)
1. Casing A. Review
B. Setting Depths
C. Connections
D. API Casing Performance Properties
![Page 43: Q922+de2+l05 v1](https://reader034.fdocuments.net/reader034/viewer/2022042513/54b51b8f4a79596f458b4706/html5/thumbnails/43.jpg)