final presentation gpii

1

UAE University

Faculty of Engineering

Graduation project II

Casing Design in a Vertical WellFinal Presentation

Dr. MD RahmanAdvisor:

Team Members: Omar Ahmed Kamel 200100051 AbdulRahman Hasan 199900460 Ibrahim Hussain Taqi 199900628 Sultan Hussain Ahmed 200106307

2

Presentation Layout

AcknowledgementIntroductionLight Casing Design For Grade SelectionHeavy Casing Design For Grade SelectionConductor Casing DesignAPI Coupling SelectionsEconomic ConsiderationsConclusions

3

Acknowledgment

We would like to express our deepest thanks and appreciation to:

1) Prof. Reyadh Almehaideb and GP Advisor MD Rahman

2) Examiners Committee: Prof.Abdulrazq Zekri, Dr. Shedid Ali and Dr. Bilal El-Ariss

3) ADCO: represented mainly by Mr. Reymond Khairallah, S.A Turki and Adib Edris

4) Training and Graduation Projects Unit

4

Introduction

Casing is defined as a heavy large steel pipe which can be lowered into the well for the following functions:

1)Keeping the hole open by preventing the weak formations from collapsing.

2) Serving as a high strength flow conduit to surface for both drilling and production fluids.

3) Protecting the freshwater-bearing formations from contamination by drilling and production fluids.

5

Introduction

4) Providing a suitable support for wellhead equipment and blowout preventers for controlling subsurface pressure, and for the installation of tubing and subsurface equipment.

5) Providing safe passage for running wireline equipment.

6) Allowing isolated communication with selectively perforated formation(s) of interest.

6

Introduction

The main types of casing are:

1) Conductor Pipe2) Surface Casing3) Intermediate Casing4) Production Casing5) Liners

As shown in the Figure

7

Project Objectives

• To perform casing design for two vertical wells by:

1) Data collection from ADCO Company.2) Selection of casing setting depths.3) Selection of casing sizes.4) Determination of number of casings.5) Selection of casings grades and couplings.6) Economic Analysis.

8

Light Casing Setting Depth Chart

Setting Depth Chart

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

EMW (ppg)

Dept

h (f

t)

Formation PressureFracture PressureTrip Margin

Depth Objective

I ntermediate Casing Shoe

Surface Casing Shoe

9

Light Casing Program

Depth (ft.) Casing Size (in.) Casing Type

0 - 150 18-5/8 Conductor Pipe

0 - 1620 13-3/8 Surface Casing

0 - 7420 9-5/8 Intermediate Casing

7420 - 8938 7 Production Liner

10

Casing Design For Grade Selection

• Casing Design for grade selection is done based on maximum load and minimum cost.

• Collapse pressure, burst pressure and tension loads are calculated for all casings to select there suitable grades.

• Pressure testing and biaxial effects are then checked for all casings.

11

Light Surface Casing Design

12

Light Surface Casing Collapse Pressure

Depth (ft) Collapse Pressure (psi)0 0

1620 724

Collapse Pressure Vs. Depth

0

500

1000

1500

2000

0 200 400 600 800

Collapse Pressure (psi)

Dep

th (f

t)

13

Light Surface Casing Burst Pressure

Depth (ft) Burst Pressure (psi)0 815.18

1620 223.88

Burst Pressure Vs. Depth

0

400

800

1200

1600

2000

0 200 400 600 800 1000

Burst Pressure (psi)

Dep

th (f

t)

14

Light Surface Casing Grade Selection


0

400

800

1200

1600

2000

0 200 400 600 800 1000


Dep

th (f

t)

K 55

L 80

H 40

J 55

15

Light Surface Casing Grade Selection


0

400

800

1200

1600

2000

0 500 1000 1500 2000 2500 3000


Dep

th (f

t)

K 55H 40 L 80

J 55

16

Light Surface Casing Tension Calculations

Grade

DepthInterval

(ft)

GradeWeight (lb/ft)

BuoyantWeight

(1000 lbf)

CumulativeBuoyantweight

(1000 lbf)

ShockLoad(1000

lbf)

TotalTension

(1000 lbf)

YieldStrength

(1000 lbf) SF

J 55 1620 - 1480 50.3 6.03 6.03 160.96 166.99 9625.7

6

H 40 1480 - 1240 46.2 9.49 15.52 147.84 163.36 5413.3

1

L 80 1240 - 730 43.4 18.95 34.47 138.88 173.35 15568.9

8

K 55 730 - 0 36.5 22.81 57.27 116.8 174.07 9625.5

3

BFWIntervalDepthWeightBouyant n

nWLoadShock 3200

LoadShockWeightBuoyantCumulativeTensionTotal

LoadShockWeightBuoyantCumulativeTensionTotal

TensionTotalY

SF pWhere BF is Buoyancy factor, Wn is casing weight in lb/ft and Yp is the grade yield strength in lbf and SF is the safety factor.

17

Light Surface Casing Pressure Testing

• Pressure testing calculation :

• Safety factor > 1.8, so H-40 can be used.• So, all four grades are safe to be used in

the light surface casing.

67.1310)65587.685.32(

105413

3

testingpressureduringTensionTotalY

SF p

18

Light Intermediate Casing Design

19

Light Intermediate Casing Collapse Pressure

Depth (ft) Collapse Pressure (psi)

0 0

2277.53 1196.16

7420 688.046


0

2000

4000

6000

8000

0 500 1000 1500


Dep

th (f

t)

20

Light Intermediate Casing Burst Pressure

Depth(ft) Burst Pressure (psi)

0 2500

5497.47 3374

7420 115.953


0

2000

4000

6000

8000

0 1000 2000 3000 4000


Dep

th (f

t)

21

Light Intermediate Casing Grade Selection


0

2000

4000

6000

8000

0 500 1000 1500 2000


Dep

th (f

t)

J 55

H 40

H 40L 80 P 110

22

Light Intermediate Casing Grade Selection


0

2000

4000

6000

8000

0 2000 4000 6000


Dep

th (f

t)

P 110

L 80

H 40

23

Light Intermediate Casing Tension Calculations

GradeDepth Interval

(ft)

Grade Weight (lb/ft)

Buoyant Weight (1000

lbf)

Cumulative Buoyant weight

(1000 lbf)Shock Load (1000 lbf)

Total Tension

(1000 lbf)

Yield Strength

(1000 lbf) SF

H 40 7420 - 6250 26 26.04 26.04 83.2 109.24 295 2.70

L 80 6250 - 0 29 155.15 181.19 92.8 273.99 658 2.40

• The grades are safe to be used. • The grades are also found suitable if the

total tension load increases due to pressure testing as the safety factor is much higher than 1.8.

24

Light Casing Production Liner Collapse Pressure


6920 737.483

8938 1421.179


6000

6500

7000

7500

8000

8500

9000

9500

0 500 1000 1500


Dep

th (f

t)

25

Light Casing Production Liner Burst Pressure

Depth (ft) Burst Pressure (psi)

6920 2311.723

8938 2118.306

Burst Pressure Calculations For Liner Design

60006500700075008000850090009500

2000 2200 2400 2600


Dep

th (f

t)

26

Light Casing Production Liner Tension Calculations

GradeDepth

Interval (ft)


BuoyantWeight

(1000 lbf)

Cumulative Buoyant Weight

(1000 lbf)

Shock Load

(1000 lbf)

Total Tension (1000 lbf)

Yield Strength (1000 lbf) SF

J 55 8938 – 7850 16.2 15.09 15.09 51.84 66.93 258 3.85

H 40 7850 – 6920 14.8 11.78 26.87 47.36 74.23 171 2.30

• Both grades are safe for use. • Here, also by calculating the additional

tension due to pressure testing it is found that the safety factor > 1.8.

27

Heavy Casing Setting Depth Chart

Setting Depth Chart

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

EMW (ppg)De

pth

(ft)

Fracture PressureFormation PressureTrip Margin

Surface Casing Shoe

1st I nermediate Casing Shoe

2nd I ntermediate Casing Shoe Depth Objective

28

Heavy Casing Program

Depth Casing Size (in) Casing Type

0 - 150 30 Conductor Pipe

0 - 1610 18-5/8 Surface Casing



9420 - 9532 7 Production Liner

29

Heavy Surface Casing Design

30

Heavy Surface Casing Collapse Pressure


0 0

1610 703.248


0

400

800

1200

1600

2000

0 200 400 600 800Collapse Pressure (psi)

Dep

th (f

t)

31

Heavy Surface Casing Burst Pressure


0 718.06

1610 130.41


0

400

800

1200

1600

2000

0 200 400 600 800


Dep

th (f

t)

32

Heavy Surface Casing Grade Selection


0

400

800

1200

1600

2000

0 200 400 600 800Collapse Pressure (psi)

Dep

th (f

t)

H 4

0

H 40 J 55

J 55 K 5

5

GradeWeight (lb/ft)

Collapse Resistance

(psi)Depth

Intervals (ft)

H 40 70.6 320 0 – 780

J 55 82.2 520 780 - 1200

K 55 93.6 790 1200 - 1610

33

Heavy Surface Casing Grade Selection

• All the Grades are suitable for the Burst Pressure.


0

400

800

1200

1600

2000

0 500 1000 1500 2000 2500


Dep

th (f

t)

H 4

0

J 55

K 5

5

34

Heavy Surface Casing Tension Calculations

GradeDepth

Interval (ft)


Buoyant Weight

(1000 lbf)

Cumulative Buoyant

weight (lbf/ft)

Shock Load

(1000 lbf)

Total Tension (1000 lbf)


K 55 1610 - 1200 93.6 32.85 32.85 299.52 332.37 1474 4.43

J 551200 - 780 82.2 29.55 62.40 263.04 325.44 1290 3.96

H 40780 - 0 70.6 47.14 109.54 225.92 335.46 804 2.40

35

Heavy Surface Casing Pressure Testing Calculations

• Pressure Testing for the weakest grade which is H 40 is done based on the following equation:

84.6)1000(034.840Pr

6.0tanRePr

FactorSafetyThelbfHForTensionTestingessure

AAreaSecntinalCrosscesisBurstTensionTestingessure s

As (in2) 10.14

Additional Tension (1000 lbf) 8.034

SF 6.84

36

Heavy Surface Casing Design Biaxial Calculations

Biaxial effect:

Where: σa is the axial stress due to tension (psi σy is minimum yield strength of the grade (psi) Ypa is the effect yield strength (psi) do is the outer casing diameter (in) di in the inner casing diameter (in)

y

a

y

ayp

io

a

Y

dd

GradeWeakestByCarriedWeightBouyant

o

5.075.01

45.0

22

37


• Biaxial effect is calculated using the following set of equations:

Where: A,B, C, F and G are empirical constants

31327

6

3162105

1036989.01010483.0030867.093.465

1050609.0026233.0

1053132.01021301.01010679.08762.2

papapa

pa

papapa

YYYC

YB

YYYA

ABFG

ABABAB

ABABY

ABAB

F

pa

/)(

/2/31/

/2/3

/2/31095.46

2

36

38


σa 2913.47

σy 40000

Yp 38463.61

do/t 53.21429

• The biaxial results for heavy surface casing:

Stress Calculations Coefficients Calculations

A 2.945766

B 0.045699

C 707.922

F 2.078155

G 0.032239

39


do/t >Model

53.2142857 > 43.30674 Elastic

• From the results:

• The collapse pressure remain unchanged (Elastic Model)

ABABtdo /3

/2/

ABAB

/3/2

Where dWhere doo is the outer casing diameter, in is the outer casing diameter, in t is the thickness of casing, in t is the thickness of casing, in

40

1st Heavy Intermediate Casing Design

41

1st Heavy Intermediate Casing Collapse Pressure


0 0

5800 2714.4


0

1000

2000

3000

4000

5000

6000

0 500 1000 1500 2000 2500 3000


Dep

th (f

t)

42

1st Heavy Intermediate Casing Burst Pressure


0 5931.28

5800 3814.28


0

1000

2000

3000

4000

5000

6000

7000

0 1000 2000 3000 4000 5000 6000 7000

Pressure (psi)

Dep

th (f

t)

43

1st Heavy Intermediate Casing Tension Calculations

• Selected grades based on collapse and burst pressures and Tension Calculation:

• The selected grades are safe and meet all the loads

Grade


Buoyant Weight

(1000 lbf)

Cumulative Buoyant

weight (1000 lbf)

Shock Load

(1000 lbf)

Total Tension

(1000 lbf)


P 110 73.1 81.35 81.35 233.92 315.27 1225 3.89

L 80 65.2 251.15 332.50 208.64 541.14 1452 2.68

44

2nd Heavy Intermediate Casing Design

45

2nd Heavy Intermediate Casing Collapse Pressure


0 0

3074.57 1838.59

9420 1277.66


0

2000

4000

6000

8000

10000

0 500 1000 1500 2000


Dep

th (f

t)

46

2nd Heavy Intermediate Casing Burst Pressure


0 2500

6705.64 3984.63

9420 2993.89


0

2000

4000

6000

8000

10000

0 1000 2000 3000 4000 5000


Dep

th (f

t)

47

2nd Heavy Intermediate Casing Grade Selection


0

2000

4000

6000

8000

10000

0 500 1000 1500 2000


Dep

th (f

t)

C75

33.

9 lb

/ftC 75 32lb/ft

C 75 32lb/ft

48

2nd Heavy Intermediate Casing Grade Selection


0

2000

4000

6000

8000

10000

0 1000 2000 3000 4000 5000


Dep

th (f

t)

C75

33.

9 lb

/ft

C 75 32lb/ft

C 75 32lb/ft

49

2nd Heavy Intermediate Casing Tension Calculations

GradeDepth

Interval (ft)


Buoyant Weight

(1000 lbf)

Cumulative Buoyant weight

(1000 lb/ft)

Shock Load

(1000 lbf)

Total Tension

(1000 lbf)

Yield Strength(1000 lbf) SF

C 75 9420 - 7250 32 59.44 59.44 102.4 161.84 559 3.45

C 75 7250 - 2700 33.9 132.03 191.47 108.48 299.95 680 2.27

C 75 2700 - 0 32 73.96 265.43 102.4 367.83 559 1.52

L 80 2700 - 0 33.9 78.35 265.43 108.48 373.91 771 2.06

• Grade C 75 of weight 32 lb/ft doesn’t satisfy tension load requirements so it is replaced with grade L 80 of weight 33.9 lb/ft.

• Pressure testing and biaxial loads will not cause any change in the selected grades.

50

Heavy Casing Production Liner Collapse Pressure


9032 1311.96

9532 1267.75


9000

9200

9400

9600

1200 1250 1300 1350


Dep

th (f

t)

51

Heavy Casing Production Liner Burst Pressure


9032 3135.96

9532 2953.01


9000

9200

9400

9600

2800 2900 3000 3100 3200 3300 3400


Dep

th (f

t)

52

Heavy Casing Production Liner Grade Selection


9000

9200

9400

9600

1200 1250 1300 1350


Dep

th (f

t) C 75

L 8

0


9000

9200

9400

9600

2900 3100 3300 3500 3700 3900


Dep

th (f

t)

C 75 L 80

53

Heavy Casing Production Liner Grade Selection

GradeDepth Interval

(ft)


Buoyant Weight

(1000 lbf)

Cumulative Buoyant

weight (1000 lbf)

Shock Load

(1000 lbf)

Total Tension

(1000 lbf)

Yield Strength

(1000 lbf) SF

L 80 9532 - 9250 15.5 3.74 3.74 49.6 53.34 358 6.71

C 75 9250 - 9032 15.3 2.86 6.60 48.96 55.56 331 5.96

• Both grades are safe for production liner

54

Conductor Casing Design

• The conductor casing is set at 150 ft for both light and heavy casing designs.

• Usually the conductor casing is driven for such shallow depth and this is also practiced in ADCO

• Conductor size is 18-5/8 in. for light casing and 30 in. for heavy casing.

• J-55 and X-65 grades have been selected finally for conductor pipe for light and heavy casing designs respectively.

55

API Coupling Selections

• Round short and long thread couplings are mostly used in the casing design.

• The same couplings are considered in both light and heavy casing designs.

• There strengths for each grade for all the casings designed so far are compared with the respective total tension load and it is found that the safety factor is higher than 1.8

56

Economic Considerations

Design Features Cost $ Savings

Single grade 721500 143142 $

Combination grades 578358 20%

Light Casing Design Cost Analysis

Heavy Casing Design Cost Analysis

Design Features Cost $ Savings

Single grade 283584 27850 $

Combination grades 255734 10%

57

Conclusions

• Collapse, burst, tension and biaxial design principles are studied carefully to apply graphical methods for casing grade selection.

• Maximum load design principles and worst loading conditions are applied for both casing designs successfully, and combination grades are selected for each casing string satisfying all constraints and meeting all loads.

• Cost analyses are performed for each casing design.

• Environmental considerations are given emphasis in both casing designs.

final presentation gpii

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