Lyons W.C. (ed.). Standard handbook of petroleum and natural gas engineering.2001- Volume 1

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'WON

.!Pv

'WON

Table

4-88

(continued)

WU

m0

DATA

-

moL

WWNT

AlTACHPD

TOOL

JOINT

DATA

YeMANIcUPRommmi

Nom.

size

4

l/2

5

112

21.82

I930

z.60

21.90

24.70

na

25.08

2435

24.71

24

1

25.60

24.83

21.34

2135

21.60

23.24

B.62

28.99

14.14

24.98

25.86

25.66

27.89

28.91

n.x

ID.

in.

1.500

3.5M)

3.500

33w

3300

3.500

4.276

4M)o

4.7711

4.670

Y*ld

*-@

in.

Tm

95.000

ELI

95.000

IEU

95.000

EU

IMWO

IEU

~~

lO5:000

EU

IUD0

IEU

135.000

EO

95000

IEU

95.000

IEV

105.000

IEU

135.000

IEU

95.000

IEU

lO5.000

IEU

95,WO

IEU

95.000

IEU

lOS.000

IEU

135.000

IEU

135.000

IEU

95.000

IEU

lOS.000

IEU

135,000

IEU

4 11/16

2.625

4

11/16 2.125

5

3.375

4

11/16 2.375

5

3.125

4

11/16

2.875

I

2.875

5

I#

3.37s

51fl

3.125

5

118

3.115

5

118

3.375

5

I@

3.375

5 1/8

3.375

5

11/16 3.62)

5

11/16 3.375

5

11/16 3.375

5

11/16 2.874

5

11/16

3.375

5

11/16

3.375

5

11/16

3.375

511116 2.874

0.1).

ID.

CUM.

in.

NC4UE.H.l

6

1/4

23/4

F.H.

6

114

1

114

NCSfflPJ

6318

3

1/2

NC4MP.H.) 6 l/4 2112

NC50lI.F.)

6318

3

I/)

NC5WI.F.)

65/8

3

NCIO(1.F.) 651.9

3

NCSO(EH.)

6

3/8

31/2

H90

6112

31C

NC5WE.H.)

6 1/2

3

1/4

5

1/2F.H. 7 I14

3

I/2

5

112P.H.

7

3

1/2

5

II2F.H.

7

1/4 3112

Fa.

7 3314

HW

7

3

I12

.OX

10

IO

10

IO

10

IO

RP.0)

7

5%*900

7

5%,900

7

596.900

7 659.740

7 659,740

7

848.230

7

848.230

7

501090

7

SOIOW

8

7 712070

553830

8

671wO

8

742000

8 8

553680

8

611960 786810

8

786810

8

629810

8

696110

8

895000

Tod

Jdoin(3)

IH)1440

I235(YO

11

211960

1325180

I287840

1436050

I128460

II7WW

1287840

I619520

1619520

1448640

1268540

1619520

1925760

I802320

1619520

125760

Tool

*(4)

Jdns

(SI

51m

44600

5Ioo 4200

51800

U6W

57280

49400

57180 49900

73640

59400

73640

59400

52050

41600

SMSO

Ill00

57530 49900

73970 71000

73030 71000

64120 62400

64120

JWM)

70870

71000

911M

85000

91120

82560

71530 71000

'79060 71wO

101650

85000

Morn

62400

P,

3

a

n

3

'd,

1

5.

2

0

Drill

String:

Composition

and

Design

757

CO""

NOW

00

rx

485

EU75

wo

3%

2

2200

3%

x

2200

3%

&

2100

3

&

1600

485

EU75

OH

1800

85

?&

1500

485

EU 75

NC26(I

F)

L$

;%

2300

3%

&

1800 3%.

!4

1500

485

EU 75

SL-HSO

3X

2

2800 3

%

&;

%

1700

2%

1500

2

6.65

E.U.55

NC26

(1.F.)

%

6.65

I.U. 75

P.A.C.

DZ7h

6.65

E.U. 75

NC260 F

)

6.65

E.U.75

SL-HW

%

8.65

w.75

O.H.

311,

2%

6.85

E.U. 75

NC31 (1.F.) 4%

6.85

E.U.75

W.O.

4%

685

E.U.75

O.H.

@3%

6.85

E.U.75

SL-HW 3%

10.40

E.U.55

NC31 (1.F.I 4%

10.40

I.U.55

E.H.

4X

10.40

I.

U.

55

NC26

(@S.H.)

a33x

10.40

E.U.55

O.H.

3%

10.40

E.U.75

NC31

(If.)

4X

10.40

I.U.75

E.H.

4%

10.40

I.U. 75

NC26

F.H.)

QJ3%

10.40

E.U.75

SL-H9O

3%

10.40

E.U.75

P.AC 03%

10.40

EU.75

O.H.

D3%

10.40

E.U.95

NC31

(I.F.) 4?

10.40

E.U.95

SL-HW

cD3h

10.40

E.U

105

NC31 (IF) LB4x

1040

E.U.

135

NC31 (IF.)

CMx

3%

9.50 E.U.75

NC38(W.O.)

Q4%

9.50

E.U.75

NC38 (I.F.) 4%

9.50 E.U.75

O.H.

a43/,

9.50 E.U.75

SL-HgO

4%

1330

E.U.95

NC38(IF.)

5

2x

11500

13.30

E.U.95 SL-i-490

027;

9700

13.30

E.U.95

H90

2%

12m

13.30

E.U.

105 NC38 (IF.)

5

a)2%

11500

13.30

EU.

135 NC4014F.H.)

5%

13.30

E.U.

135 NC38(3'/2

I.F.)

5

D%

:%

15.50

E.U.75

NC38(I F.)

5

2%

11000

15.50

E.U

95

NC38

(I

F.)

5

We

11500

15.50

E.U.

105 NCa(4F.H.)

5%

2%

15oOo

4):

!?&

11500 4%

x

9700

4:;

!?&

8100

758

Drilling

and

Well Completions

Table

4-89

(continued)

12

3

4 5 6 7 69 10 1112 13 1415 18

4 11.85

11.85

14.00

15.70

4% 13.75

13.75

16.60

E.U.75 NCM(1.F.)

W

E.U. 75 NC46

(W.O.)

5$

E.U.75 O.H.

E.U.75 H90

5%

I.U. 75 NC40 (F.H.) 5%

E.U. 75 NC46 (I.F.)

5%

I.U. 75

E.U.75

%%?

E.U.75 H90

5%

I.U. 95 NC40 (F.H.) 5%

E.U.95 NC46 (I.F.) 5%

1.U

95

HBO

5%

I.U. 105 NW(F.H.)

5%

E.U. 105 NC46 (1.F.)

5%

I.U. 105 H90

5%

E.U. 135

NC46

(I.F,) 6

I.U. 55 NC40 (F.H.) 5Y

E.U. 55 NC46 (1.F.)

d

I.U. 75 NC40 (F

H.)

5Y

E.U. 75 NC46 (I.F,)

52

E.U.75 HBO

5%

I.U.

95

NC40 (F.H.)

5%

E.U.

95

NC46 (1.F.)

5%

I.U.95 H90

5%

E.U. 105 NC46 (1.F.)

5X

I.U. 105 HBO

5%

I.U. 135 NC46 (I.F.) 6%

E.U. 135 NC46 (I.F.) 6%

E.U. 75 NC50

(W.O.)

6%

E.U.

75 NC50 (I.F.) 6%

E.U.75 O.H.

5%

E.U.75

HBO

6

I

U.55 F.H.

5%

I.U.

55

NC48 (E.H.) 6

E.U.

55

NC50 (1.F.) 6%

I.U.75 O.H.

05%

I.U.75 F.H.

5%

I.U. 75 NC46 (E.H.) 6

E.U. 75 NC50 (I.F.) 6%

E.U.75 H90 6

I.U.95 F.H. 6

I.U. 95 NC46 (E.H.)

8

E.U. 95 NC50 (I.F.) 6%

I.U.95 H90 6

I.U.105 F.H. 6

I.U. 105 NC46 (E.H.) 6

E.U. 105 NC50 (I.F.) 6%

I.U. 105

H80

6

18ooo

15400

11300

18500

12500

18ooo

8ooo

14ooo

18500

lso00

18ooo

18500

16OOO

leo00

18500

22000

13500

18ooo

13500

18ooo

18500

15700

leo00

16500

2MM)

18500

24900

23500

17500

19700

lo800

2woo

lW

1BMx)

19700

19800

leo00

19700

2woo

leo00

21000

21500

23500

20300

22OOO

22ooo

23500

5800

6500

8600

6OOO

7600

7200

8wo

7400

6900

9400

gsoo

goo0

lO6W

lo300

lo800

13300

5800

8200

8ooo

7500

logoo

lo300

8800

11700

11400

14800

8800

8500

8400

6800

7300

7100

10200

8600

gsoo

lo200

12500

13ooo

12700

14100

lloo

13900

1380Ll

Drill

String:

Composition

and

Design

759

4% 16.60 I.U.135 NC46(E.H.)

6Y

16.60 E.U.135 NCM(1.F.)

6i

25.60

I.E.U.105 5XFH 7%

3%

37000

6%

X

33700

6Y:.

?&

27500

6%

L

23100

5%

21.90

I.U.75

F.H.

7

4

28800

X,

24200

6%

X

18800

6%

X

1660

21.90 l.E.U.95 F.H. 7

3%

32300

6%

?&

296W

30000 67:

6x,

"'

g

24200

24300

ri

'9'

g

20900

20800

21.90 l.E.U

95

HW

7

3%

303MI

6%

21.90 I.E.U.1W F.H. 7% 3% 37000

X

33200

6!!&

X

27500

6%

?&

23100

21.90

I.E.U.135

F.H.

7%

3 44100 7%

?&

42300

6%

?'$

34300

6%

X

29800

24.70

I.U.75

F.H. 7 4

28800

6?&

X

26400

%

22Mx)

6?&

%

17700

24.70 i.E.U.95

F.H.

7%

3%

37000

6?&

!?&

33200

6%

2%

275W

6%

?&

23100

2470

I.E.U.

105 F.H. 7%

3%

37060

61L

N,

36500 6%

%

29800

6%

%

25300

.'.

_,r

~ ~~~

-,-

.I

.- .-

..

.-

~

.

~~

@Basis

ot

calculations

lor

meommended

tool

joint makwp toque asmmed

the

use

of

a thread compound Conlainmg 40-

6046

by

weight Of

linely

powdered

metallic

Zinc

applied lhmughly to

all

threads and Shoulders. and a tensile

slr~sof62.500~SilorcOlumn7and75.000psiforcolumnsl0.l3.and

16.

@W%

minimum

wall

dnll pip.

0.0.

of

tool

joinls

listed

lor

Premium

Class

drill pipe are

bawd

on

drill pipe hawing uniform

y(larlllQ

a minimum

wal!

thrcknar

olBo9b.

OMinimum

box

Shoulder disregards bevel.

a0.D.

01

1001

joints shown

tor

class

2

dnll pipe

we

baled

on

drill pip hawing

all

the

wear

on

one aide and

a

minimum wall

thtckness

01

65%.

W.0.

of

tool

loints

shown

for

Class

3 drill

pipe

are

bow

on

dnll

pipe having all Me

war

on

one

side

and

a

minimum

wall thickness

01

5%.

@The

uae

of

0

0:s

smaller lhan lhoae listed

on

lhe

fable

may

be

aceaptable

on

Slim Hole Tool Joints due

la

special sewice

rsquiremsnts.

mTml

Joint

with dimensions shown ha8

a

lower

torsional yield Mrength lhan

the

drill pipe

M

which

il

is atlached.

*Tool

joint

wtsrde

diameters

(OD)

specified

are

required

to

retain Iorsional strength

In

lhe tool Joint comparable to Ihe

torsional strength

of

the allshed drill pipe,

The

use

01

tool joints, with oulaide dismat?rr smaller than those listed

may

be

acceplabb

in

special mice requirmls 10 provide sutticlenl clearance

in

Cmmng

programs.

In

Such cases.

the torsional

strength

01

the

joint

may

be

cmderaWy

below

that

01

the

drill pip.

body

to

which

it

la

attached.

Tool

ioinn

with

OuW

dimnn

Im

from

Grde

E

drill pipe

an

deqwta

for

hogh

rtnngth

drill pipa

when

4

in

-be

Ntmn

srrmg

with

GRd.

E

drill

prim.

760

Drilling and Well Completions

/EXTRA

LONG

JOINTS

(A) MORE BEARING

AREA REDUCES

WEAR

(6)

MORE LENGTH

FOR

RECUTTING

CONNECTIONS

1

HARDFACI

NG

ON EIJDS AND

TION (OPTIONAL)

FOR LONGER

LIFE

CENTER SEC-

HEAVY

WALL

TUBE

PROVIDES

MAXIMUM WEIGHT

PER FOOT

CENTER UPSET

OF TUBE

ON CENTER

OF

TUBE

(A)

INTEGRAL PART

(B)

REDUCES WEAR

EXTRA

LONG

JOINTS

(A) MORE BEARING

AREA REDUCES

WEAR

(6)

MORE LENGTH

FOR

RECUTTING

CONNECTIONS

Figure

4-134.

Drilco's Hevi-Wate' drill pipe

[42].

(text

continued

from

page

749)

drilling. However, based on field experience, if a heavy-weight drill pipe above

the drill collars is used, it reduces drill pipe failure. The failure of regular drill

pipe and tool joints is influenced by several factors. Probably the most important

one is a cyclic bending stress reversal resulting from the accidental running of

drill pipe in compression, the centrifugal force effect

or

passing through short

and sharp dog-legs,

or

a combination of these factors. In directional drilling, a

Drill String: Composition and Design

761

heavy-weight drill pipe is used to create weight on the bit if, for some reason

(e.g., excessive torque and drag or differential problem sticking), a long string

of drill collars cannot be run.

The best performance

of

the individual members of the drill string is obtained

when the bending stress ratio of subsequent members is less than 5.5

[38].

Bending stress ratio (BSR) is defined as a ratio of the bending section moduli

of two subsequent members, e.g., between the drill collar and the pipe right

above it.

To

maintain the

BSR

at less than 5.5, the string of drill collars must frequently

be composed

of

different sizes. For severe drilling conditions (hole enlargement,

corrosive environment, hard formations), reduction of the

BSR

to 3.5 helps to

reduce frequency of drill pipe failure.

Geometrical and mechanical properties

of

heavy-weight drill pipe (Hevi-Wate@)

manufactured by Drilco are given in Table

4-90.

Example

Calculate the required length

of

44

in. Hevi-Wate" drill pipe for the following

conditions:

Hole size:

94

in.

Hole angle:

40"

Desired weight on bit:

40,000

lb

Drill collars:

7

x

2z

in.

Length of drill collars: 330 ft

Drilling fluid specific gravity:

1.2

Desired safety factor for neutral point: 1.15

Solution

Check to see if the

BSR

of drill collar and Hevi-Wate") drill pipe is less

Bending section modulus of drill collar is

than 5.5.

Bending section modulus

of

Hevi-Wate" drill pipe is

BSR

=

-

65*592

-

4.26

e

5.5

15.397

Unit weight

of

drill collar in drilling fluid is

110

1--

=

93.181b/ft

(

;.s25)

762

Drilling

and

Well Completions

Nom

SI28

(In)

5

Table

4-90

Properties

of

Hevi-Wate@ Drill Pipe

(@

Drilco Trademark)

[38]

DIMENSIONAL DATA RANGE

II

Muh

Pmpwiln

Nom Tub.

Tub.

Dhnensbn

&cIlon

TUBE

wall

Tor-

Tblck-

Center

Elentor

Tenslla

slo~l

ID

nns

Awa

Upul UpwI VIeY Yldd

(In)

(In,)

(In1

(lb)

(H-IO)

2%

075 9.965

5

4%

546.075 40,715

3

l.W 12.656

5% 5'/8 691.165

56,495

I

TOOL

J

m

NNT

WEIGHT

ma.

WI

InJ

Tuba

L

Jolnls

(IO)

Mako-

UP

TOrqUI

(lt-lb)

9.W

-

13.251

21.m

29.m

DIMENSIONAL DATA RANGE

111

TOOL JOINT

I

WEIGHT

1

I

Ill

Appma.

WI

lncl

Drill String: Composition and Design

763

Unit weight of Hevi-Wate(') drill pipe

=

(41)(0.847)

=

34.72 Ib/ft. Part of weight

on bit that may be created using drill collars

=

(93.18)(330)(cos

40)

=

23,555 lb.

Required length of Hevi-Wate'') drill pipe is

(40000-

23555)(1.5)

=

,llft

(34.72)(cos40)

Assuming an average length of one joint of Hevi-Wate(c) drill pipe to be 30 ft,

24

joints are required.

Fatigue Damage

of

Drill

Pipe

It should be understood that the majority of drill pipe and tool joint failures

occur as a result of a fatigue damage. The problem of fatigue failure is not

adequately researched; however, it is basically agreed that tension and bending

(reversing tension and compression of the same drill pipe fiber), magnified by

vibrations, contribute the most to such type of failure. Cycling stress results in

a

crack that spreads across the cross-section and causes ultimate failure.

A

fracture begins at a point on or near the surface that is weaker than any other

due to a number of reasons (e.g., surface imperfections

or

stress raisers). Fatigue

cracks can also initiate at points below the surface of the drill string

if

the

proper conditions exist. It should also be remembered that drill pipe fatigue

is

cumulative in nature,

so

the changes that affect failure are usually long delayed

and require a certain amount

of

time to be detected.

The drill collars and particularly their connections are also exposed to cyclic

stresses. Subsequently, these are susceptible to fatigue damage, but the changes

that may influence failure are more quickly discovered.

Based on work done by

A.

Lubinski,

J.

E.

Hansford and

R.

W.

Nicholson (API

RP

7G,

Section

6),

gives the formula for the maximum permissible hole curva-

ture

in

order to avoid fatigue damage to drill pipe.

432,000

G,

tanh(

KL)

c=--

=

ED,,

KL

K

=

(6)"

For Grade

E

drill pipe

(T,

=

19,500

-

(0.149)~~

=

1.34

(4

For Grade S-135 drill pipe

Ob

=

20,000

1

-

(

14;kOO)

33,500)2

(4-66)

(4-6'7)

(4-68)

(4-69)

(4-70)

T

0,

=

-

A

764

Drilling and Well Completions

where c

=

maximum permissible dog-leg severity in "/lo0 ft

ob

=

maximum permissible bending strength in psi

G~

=

tensile stress due to the weight of the drill string suspended below a

E

=

Young's modulus,

E

=

30

x

lo6

psi

D,,

=

outside diameter of drill pipe in in.

L

=

half the distance between tool joints, L

=

180 in. for Range 2 drill

pipe. Equation 4-75 does not hold true for Range

3

drill pipe.

T

=

weight of drill pipe suspended below the dog-leg in lb

A

=

cross-sectional area of drill pipe in in.*

dog-leg in psi

I

=

drill pipe moment of inertia with respect to its diameter in in.4

By

intelligent application of these formulas, several practical questions can be

answered, both at the borehole design state and while drilling.

Example

Calculate the maximum permissible hole curvature for data as below:

New EU 444.. Range 2 drill pipe, nominal weight 16.6 lb/ft, steel grade

S-135, with NC50

(IF)

tool joint

Drill collars,

7

x

2$ in., unit weight 117 lb/ft

Length of drill collars, 550 ft

Drilling fluid density, 12 lb/gal

Anticipated length of the hole below the dog-leg, 8,000 ft

Assume the hole is vertical below the dog-leg

Solution

From Table 4-79:

Ddp

=

4.5 in., ddp

-

3.826 in.,

A

=

4.4074 in.; and from Table

Weight of drill collar string is

4-100: unit weight of drill pipe adjusted for tool joint, WdP

=

18.8 lb/ft.

(550)( 117) 1

-

=

52,543 lb

(

6i24)

Weight of drill pipe is

(8,000-550)(18.8) 1--

=

114,3611b

(

6i24)

Weight suspended below the dog-leg, T

=

166,904 lb,

166,904

4.4074

Tensile stress

tst

=

-

=

37,869 psi

Maximum permissible bending stress,

(2,

=

20,000 1

-

=

14,7761b

(

1345

,EO)

Lyons W.C. (ed.). Standard handbook of petroleum and natural gas engineering.2001- Volume 1

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