Mitchell DD Chapters

8/11/2019 Mitchell DD Chapters

1/182

OILWELL

DRILLING

ENGINEERING

&

computer

p r o g r a m s

MITCHELL


2/182

T LE OF CONTENTS

ClIAP IER I IUBl JIAR DESIGN NDUSE 1

Tubular Design

and use ; l

Failure Theories 1

Tubular

End Conditions 1

N

ames

of

Casings

, 2

Loads

2

Salt

and

Diaperic Shale

6

Casing Design Criteria 7

Management

I

s

Guidelines

7

Popular Desigri

Factors

:

Drilling Burst Criteria

n

Overview

of

Casing

Selection

3

Minimum Tubular

Strengths 4

Failure Mode

5

Triaxial

Equation

6

Real Gas

Fundamentals of Tubulars

22

Stress Analysis

Z

Effective

Tension r

Buoyed

Weight

3

Free

Bodies 34

Stretch

and

Wall

Strains 4

Change

in

the

Diameter

of

a Tube .41

Bending Stress in Doglegs 49

Lubinski Bending Stress 49

Buckling

v.

Tension

Compression

53

Critical Buckling Events of Casing 54

Buckling Tendency

Wellhead

Load

57

Intermediate Casing Design

63

Tubular S trengths

68

API

Collapse

Resistance

API Internal Pressure Resistance 75

Pipe Body Yield Strength 79

API

Hydrostatic Test

Pressures 82

Tolerances on

Dimensions 83

Make up

Torque

for

API Couplings

86

Round

Thread with Bending and Tension 86

Tubular Connections 89

Slack-off

Bending

Loads

Surface Running Loads 92

Dogleg

Running

Loads 92

Tubing Design

Dri llpipe Des ign fJ7

Combined Tension, Torsion,

Bending

Pressure

Loads ,

8

Von Mises Stress 8

Slip

Crushing

116

TABLE OF CONTENTS 1

MITCHELL x 1492 Golden

O

8 4 2


3/182

Fatigue

of

Drillpipe 7

Life ofDrillpipe 2

Casing Tally

22

Casing Centralizer

Spacing 25

Casing

Sag between Centralizers 27

Wall Force Equation 29

Helical Buckled pipe

length

3

CHAPTER

n

DRJI IJNG OPTIMIZATION METHODS 144

Cost

per

foot Equation

44

Time Value of Money 47

Expected

Value Method 48

Lagrangian Multiplier 53

Multiple

Regression

with

Least Squares 56

Confidence Lines

Lagrange s

Interpolation Formula

62

CHAPTER III DRILL

HOLE

MECHANICS I6 4

Selecting

Casing

Setting

depths 65

Stresses

around

a Drill Hole

68

Leakoff

Test

7

Fractures

in

a Drill Hole 174

Fracture

Gradient Plot 8

Filtration

of

Mud into th e Formation 82

Barite Water

required to drill a Section

of

Hole

83

Solids Concentration Selection 85

ClIAPrER IV

KICK

REMOVAL ...........................192

Kill Parameters 97

Initial Conditions

97

Drillers Method 99

Engineer s Method 2 4

Kick Control Worksheet 2

Gas M igra tion 2 7

Recogni

tion

223

High

Weight Pill 223

Barite Plug

Filling

the

Hole on Trips .. 228

Novel Techniques 229

CHAP rER

V R H Y D R ~ I S ..............................

zra

Effect

of Mud Weight on Bit Hydraulics 243

Bingham s

Drilling efficiency

Diagram 246

Optimal Bottom Hole Cleaning 249

T he or y o f

Maximizing

Impact

Force

259

Effect

of Mu d

Weight

of

Bi t Hydraulics

26

Hole

Cleaning 262

Drill

Cuttings

concentration in

the Annulus

264

Hopkin s

Particle Slip Velocity Chart 267

TABLEO CONTENTS

MITCHELL Box 1492 Golden

O

8 4 2


4/182

Oribital Motion

of the

Drill

String

274

Surge and Swab for Long Pipe Strings

276

Surge

and

Swab

Pressures

of

Short

Tools 285

Circulating

Pressures

for

Short

Tools

i57

Equivalent Circulating Density 289

CH PTERVI DffiECTION L RaLING 292

Directional Drilling 292

Directional well planning

fJ

Transposing

MD

t o TVD 306

Tie Point and Collision :

310

Kill Well Design 314

Leading

the Target with planned walk 316

Dogleg Severity of Holes 319

Dogleg-abrupt 32D

Wilson s Equation

322

Monitoring of a Directional Well 325

Radius

of Curvature

327

Sectional Method and Minimum Curvature 331

Stability of Computational Surveys 338

Errors in Surveying

343

Ellipse of Uncertainty 343

Systematic and Random Errors by Warren

346

Circle

of

Uncertainty 347

Declination Changes 350

Drilling

String

Measurements 350

Magnetic

and other

Interferences 351

Hot Spots BHA 352

People Recording Errors 353

3 Dimensional Drill Hole Planning

355

Tool Face Rotation

359

CIl P IERvn

HORIZONr L DRll LING m

Uses

of Horizontal Well 373

Horizontal Dri ll ing 373

Types of Horizontal Wells

374

Horizontal Well Costs 376

Casing

Drill

bi t

sizes 378

Equipment 381

Directional Drilling subs and stabilizers 384

ottom Hole ssemblies

386

Length of non-magnetic Drill collars 388

Trajectory Planning

Vertical Turn to

aNew

Track m

Selection of Mud Weights

399

Drill

bi t

Hydraulics

403

Torque and

Drag

405

Friction factors 409

Buckling of

the

Drill String .414

TABLE OF CONTENTS

111

MITCHELL Box 1492Golden CO8 4 2

CAPITULO VII PERFORACION HORIZONTAL

CAPITULO VI PERFORACION DIRECCIONAL


5/182

Lock up of

the

Drill String 415

Available Torque for

th e

Drill bi t

415

Cementing

Problems 418

Cement

Sheath

within Casing

418

Conveyed Logging 419

Case

Histories

42

Austin

Chalk Well

42

Tyra

field

offshore Denmark 4

CH PTERVIII OTTOM HOLE

ASSEMBLIES...............................

427

Purpose of BHA l

Type

of BHS s

4Z l

Discussion

of Components 429

Mechani cal P ropert ies of

BHA

43

Tapered . BHA 436

Usable Hole Diameter 438

Centrifugal Force

:

44

Torsional

Dampening 441

Torque

of a

Spinning BH A

442

Torsional Buckling

of

a BR A and Drillpipe 443

Buckling by Rotational Drag

445

Critical

Buckling Load

446

Weight on Drill

bit

in Veritcal

and

Inclined Holes 447

Critical

Rotary Speeds of BHA

.450

Placement

of the Pendulum Stabilizer

453

Packed

BR A 458

Directional

BHA

46

BH A Connections 46

Make up of Connections

464

Identification of Connections

and

Drillpipe 464

ClIAP I ER:IX.

AIR

DRII...LIN G

Advantages and Limitations of Air/Gas 467

Air

Drilling

Equipment

Pneumatics and

Hydraulics .476

Pressure Losses in Pipe and Fittings .478

Ai r Temperature

Increas es o n

Compression

.480

Air

Pressure

Requirements

481

Mist Drilling Volumes

and

Pressure Requirements 486

Foam

Drilling

Volumes and Pressure

Requirements 486

Aerated

Mud Volume

and

Pressure Requirements

488

IKOKU 488

Operational Procedures 489

Concentric Drillpipe an d the Jet Su b .494

Parasite String

494

Safety

Practices 499

CH PTER X CEMENT fj l

On e

Dozen Cementation Problems 506

TABLE O CONTENTS iv MITCHELL Box 492Golden

O

8 4 2

CAPITULO VIII ENSAMBLAJES DE FONDO (BHA)


6/182

Solutions to a Dozen Problems

5 6

Balanced Plug Cementation Formula 5 6

Cementation Temperatures 5 7

CH PTER XI DRILL

IT

SELECTION

...................................

522

Drill Bit

Characteristics

525

Rock

Bit

Terminology

Zl

Rock Failure Models 528

Drill Bit Selection Criteria 528

Trip

Time 53

Optimal Weight on

Bit Rotary

Speeds 53

Contour

Method

53

nalytical Method

533

Optimal

WOB Rotary Speed

Charts 539

Diamond

Bit

Hydraulic Lift Off 545

Dull Bit Grading 547

CIl P rERXII

ISHIN G

Definitions

55

To Fish or Not to Fish ;

55

When

to

Stop Fishing

552

Break even Charts 553

Expected Value Method 554

Confidence Lines

Least

Squares

556

Differential Sticking ; OO

Mechanics of Differential Sticking >

Freeing

Differentially

Stuck

Pipe 56

Jars

and Accelerators

566

Back off 569

Free Point

569

Free Point

Procedures

569

Free

Point

with

Pipe

Stretch 569

Back-off Procedure

57

Latching on to a

Fish 573

Overshot Specifications

574

Mi

lling 575

Washover Pipe 578

Rotary

Shoes

578

Perforation

of

Pipe

58

Perforating

Procedure

58

Fishing Wire Line Tools

582

Fishing

small

objects

585

Fishing

Drill Collars

586

Fishing

Drillpipe 586

Back-offDepth

f

Cutting of Tubulars

588

Sidetracking 589

Whipstock .. ..59

PDM snd Bent sub 59

T LE OF

CONTENTS

v


CO

8 4 2


7/182

ement Plugs

for idetrack

59

ommon

Fishing ools

59

ottom Hole Motor 597

~ ] [ ~ ~

TABLE OF

CONTENTS

MITCHELL Box

49 Golden

CO8 4


8/182

H PTER VI

DIRECTIONAL

DRILLING

INTRODUCTION

Directional wells are defined as those wells

which

are to follow a prescribed

traverse and intersect

a specific objective.

Th e

objective is called a

target and is

usually an

enclosed

area in a horizontal

plane.

A target could

be

a circular area

at the top of

a producing zone.

If tolerance in the deviations

of

the

well

from the planned tr av er se is

critical t he t ra ve rs e is

usually

specified as a

cylinder

surrounding a

section

of the

hole;

otherwise the traverse

is given

as

a

line

path

between

the rotary table and

the target.

BOH5

tvd

build radius

target

B hang angle

X build

~ n t n g l e

Y slant

drop

T

U vertical

8 4

B 5

8 8

The

horizontal view depicts

north

south and east-west axis which intersect

in the

center of the

rotary table. Th e

target the traverse and directional

stations are recorded on th e two charts.

The axis

of

the

horizontal

view

may

represent

magnetic directions

if

it is desired.

N

Popular v is ua l p re se nt at io ns of T 0

directional

well

data

are on charts called

horizontal and

section

views. Th e section

view is a vertical

cross-section

drawn

th rou gh th e c en te rs of

th e

rotary

table

and KOP

1

the target.

Th e primary

purposes of the two views are to

pictorially

show

deviations of

the drilled traverse from th e planned traverse and t he progress of the

hole

relative

to

the target.

DIRECTIONAL DRILLING

292


CO

8 4 2


9/182


10/182


11/182


12/182


13/182


14/182


15/182


16/182


17/182


18/182


19/182


20/182


21/182


22/182


23/182


24/182


25/182


26/182


27/182


28/182


29/182


30/182


31/182


32/182


33/182


34/182


35/182


36/182


37/182


38/182


39/182


40/182


41/182


42/182


43/182


44/182


45/182


46/182


47/182


48/182


49/182


50/182


51/182


52/182


53/182


54/182


55/182


56/182


57/182


58/182


59/182


60/182


61/182


62/182


63/182


64/182


65/182


66/182


67/182


68/182


69/182


70/182


71/182


72/182


73/182


74/182


75/182


76/182


77/182


78/182


79/182


80/182


81/182


82/182


83/182


84/182


85/182


86/182


87/182


88/182


89/182

H PTER VII

HORIZONTAL

DRILLING

USES OF

HORIZONTALWELL

Horizontal

wells

are directional wells drilled with an

inclination

angle near 90

degrees.

The purposes of

drilling

horizontal wells are not new. However, the

application

of solid state electronics

in directional drilling

at long last

permits the

fulfillment

of those purposes.

The

primary

purposes of

horizontal wells are the

following:

1.

Intersect many fractures in a hydrocarbon containing formation.

Very popular

in

limestone

and

some

shale

formations.

2.

Avoid dri ll ing into water

below or

gas

above

hydrocarbons or

perforating adjacent

to water or gas.

Either

are thought to

promote gas

and water coning. Popular in

formations containing

relatively thin oil zones as compared with the

underlying

water

zone.

3.

Increase both

the

drainage

area

of the

well in

the reservoir and the

lateral surface area

of the well

bore. The

first .is

thought to

increase the

cumulat ive hydrocarbon product ion,

while the

second

enhances the hydrocarbon production rate.

Popular

in

formations

containing

heavy

oil.

These

holes

may

be

thought of

as

drain holes in

.some

cases.

4.

Intersect layered reservoirs

at

high

dip angles.

5.

Improve

coal

gas

production degasification .

6. Improve injection of

water,

gas, steam, chemical,

and

polymer

into

formations.

The

counter

proposal to

the

drilling

of a horizontal well is

to

drill a

vertical

well

and

hydraulically fracture the pay

formation.

This rarely

accomplishes

a

purpose

of a horizontal well,

because

hydraulic fracturing rarely if ever succeeds in

intersecting many fractures in a naturally fractured formation;

fractures

usually

intersect underlying water zones, and fractures filled with propants sand are

not drain holes.

The above purposes stipulate

the requirements for

the evaluation of

a horizontal

hole.

1. Hits al l targets

2.

Smooth turns

and

builds

for promoting long lateral sections

HORIZONTAL DRILLING

MITCHELL

Box

492 Golden 8 4 2


90/182


91/182


92/182


93/182


94/182


95/182


96/182


97/182


98/182


99/182


100/182


101/182


102/182


103/182


104/182


105/182


106/182


107/182


108/182


109/182


110/182


111/182


112/182


113/182


114/182


115/182


116/182


117/182


118/182


119/182


120/182


121/182


122/182


123/182


124/182


125/182


126/182


127/182


128/182


129/182


130/182


131/182


132/182


133/182


134/182


135/182


136/182


137/182


138/182


139/182


140/182


141/182


142/182


143/182

H PTER VIII

BOTTOM HOLE

ASSEMBLIES

DEFINITION OF BHA

A

bottom

hole

assembly

(known

as

BRA)

is

a component

of

a drill

string.

A BHA

resides

in

the drill

string above

the

drill bit

and

below

the

drillpipe.

The primary

component of the BHA

is the

drill collar. The following figure

shows

the possible

components

of

a

BRA

and

their

typical location

within

a BHA.

PURPOSEOFBHA

The purposes

of

a BHA

are as

listed

in

the

following.

1. protect the drillpipe

in the

drill

string

from excessive bending

and

torsional

loads,

control direction and inclination in directional holes,

3.

drill more vertical

holes,

4. drill straighter

holes,

5. reduce

severities

of

doglegs,

keyseats,

and ledges,

6. assure

that

casing

can

be run

into

a hole,

7

increase

drill bit performance,

8.

reduce rough

drilling, (rig

and drill string vibrations ,

9. as a tool

in

fishing, testing,

and

workover operations,

1 not

to pl ce weight on the drill it

TYPES OF BHA S

The

SLICK

BRA

is composed only

of

drill collars. It is lea st expensive

and

perhaps carries the least

risk

in regard to fishing and recovery.

The PENDULUM

BHA

is

designed to

drill

holes

more vertically

and to drop

inclination in inclined

holes. Lubinski

and

Woods

published tables

and

charts

to

locate the lowest most

stabilizers

in the BHA.

Most BHA theories

which were

intended

for vertical holes apply to holes wliich

are

inclined 20 degrees

or

less.

The PACKED BRA is designed

to

drill

straight

holes

and

to reduce

the

severities of doglegs, keyseats,

and

ledges. It provides the highest assurance that

casing can be

run into

a hole.

The

theory

which

supports the

packedBHA

was

developed by Roch. A

packed

BHA can be expensive and perhaps

carries

the

highest

risk in regard to fishing and recovery.

The

DIRECTIONAL BRA is

designed

either

to

turn the

hole to a chosen

inclination and direction or

to

maintain

a

course selected

for the hole.

The

directional

BRA is based

on the principles

of levers

and fulcrums.

BOTTOM HOLE ASSEMBLIES

4 7

MITCHELL Box 492Golden CO

8 4 2


144/182


145/182


146/182


147/182


148/182


149/182


150/182


151/182


152/182


153/182


154/182


155/182


156/182


157/182


158/182


159/182


160/182


161/182


162/182


163/182


164/182


165/182


166/182


167/182


168/182


169/182


170/182


171/182


172/182


173/182


174/182


175/182


176/182


177/182


178/182


179/182


180/182


181/182


182/182

Documents

Mitchell DD Chapters