LESSON 11 Directional Drilling
Download
Report
Transcript LESSON 11 Directional Drilling
Petroleum Engineering 406
Lesson 20
Directional Drilling
(continued)
1
Lesson 17
- Directional Drilling cont’d
Tool-Face Angle
Ouija Board
Dogleg Severity
Reverse Torque of Mud Motor
Examples
2
Homework:
READ:
Applied Drilling Engineering”, Chapter 8
(to page 375)
3
Solution
Tool Face (g)
Fig. 8. 30: Graphical Ouija Analysis.
4
Over one drilled interval (bit run)
GIVEN:
a = 16
o
Solution
Tool Face (g)
De = 12
o
aN = 12
o
De = 12o
o
Initial Inclination = 16
g=?
o
b=?
o
Fig. 8. 30: Graphical Ouija Analysis.
5
Fig. 8.33
b
a
aN
De
Basis of chart
construction is a
trigonometric
relationship
illustrated by two
intersecting
planes
b = dogleg angle
6
Problem 1
Determine the new direction (eN) for a
whipstock set at 705 m with a tool-face
setting of 450 degrees right of high side
for a course length of 10 m.
The inclination is 70 and the direction is
N15W. The curve of the whipstock will
cause a total angle change of 30/30 m.
7
Problem 1
a=7
o
e = 345
o
(inclination)
(azimuth)
g = 45
o
g = 45
(tool face angle)
L = 10 m
(course length)
o
d = 3 / 30 m
(dogleg severity)
o
eN = ?
o
8
Solution to Problem 1, part 1
I. Use Equation 8.43 to calculate b .
The dogleg severity,
b
d (i)
L
d L 3 10 m
o
b
1
i
30 m
9
Solution to Problem 1, part 2
2. Use Equation 8.42 to calculate the
direction change.
De arc tan
tan b sin g
sin a tan b cos a cos g
De tan
tan 1 sin 45
1
sin 7 tan 1 cos 7 cos 45
De tan
1
0.092027 5.3
New direction =3450 +5.30 = 350.30 = N9.7W
10
Problem 2
Determine where to set the tool face angle, g
for a jetting bit to go from a direction of 100
to 300 and from an inclination of 30 to 50.
Also calculate the dogleg severity, assuming
that the trajectory change takes 60 ft.
a=3
aN 5
e = 10
e
Find
g and d
e N 30
L 60 ft
11
Solution to Problem 2, part 1
1. Find b using Equation 8.53
b cos 1cos De sin aN sin a cos aN cos a
1
cos cos 20 sin 5 sin 3 cos 5 cos 3
o
o
o
o
o
cos 1 0.999116 2.4097o
12
Solution to Problem 2, part 2
2. Now calculate g from equation 8.48.
g cos
g cos
1
1
cos a cos b cos aN
sin a sin b
cos 3o cos 2.4097o cos 5o
o
o
sin 3 sin 2.4097
g cos
1
0.7052 45.15
o
13
Solution to Problem 2, part 3
3. The dogleg severity,
b
2.4097
d (i)
100
L
60
o
d = 4.01o / 100 ft
Alternate solution: Use Ouija Board
14
Fig. 8.31: Solution to Example 8.6.
15
Problem 3
Determine the dogleg severity following a
jetting run where the inclination was changed
from 4.3o to 7.1o and the direction from N89E
to S80E over a drilled interval of 85 feet.
1. Solve by calculation.
2. Solve using Ragland diagram
a 4.3o
e 89
o
aN 7.1o
L = 85 ft
Da = 7.1 - 4.3 = 2.8.
eN 100
De = 100 - 89 = 11
o
16
Solution to Problem 3, part 1
1. From Equation 8.55
2 Da
2 De
2 a aN
b 2 sin sin
sin
sin
2
2
2
1/ 2
2 2.8
2 11
2 4.3 7.1
b 2 sin sin
sin
sin
2
2
2
1/ 2
1
1
b = 3.01
o
17
Solution to Problem 3, part 1
1. From Equation 8.43
the dogleg severity,
b
3.01
d
(i)
100
L
85
d 3.5 / 100 feet
o
18
Solution to Problem 3, part 2
2. Construct line of length a (4.3o)
Measure angle De
(11o )
Construct line of length aN (7.1o)
Measure length b
4.3
(Measure angle g)
o
b
11
Ragland Diagram
7.1
19
Some Equations to Calculate b
Eq. 8.53
b arc cos(cos De sin aN sin a cos a cos aN )
Eq. 8.54
cosb cosDe sinaN sin a cos Da sin a sin aN
Eq. 8.55
Da
2 De
2 a aN
b 2 arc sin sin
sin
sin
2
2
2
2
20
Overall Angle Change and
Dogleg Severity
Equation 8.51 derived by Lubinski is used
to construct Figure 8.32,
a nomograph for determining
the total angle change b and
the dogleg severity, d.
21
Fig. 8.32: Chart
for determining
dogleg severity
22
(aaN)/2 = 5.7
o
aN a = 2.8
o
b=3
o
De = 11
o
d = 3.5 /100 ft
o
23
(aaN)/2
o
= 5.7
De = 11
o
24
aN a = 2.8
o
b=3
o
25
b=3
o
d = 3.5 /100 ft
o
26
(aaN)/2 = 5.7
o
aN a = 2.8
o
b=3
o
De = 11
o
d = 3.5 /100 ft
o
27
Problem 4 - Torque and Twist
1.Calculate the total angle change of
3,650 ft. of 4 1/2 inches (3.826 ” ID)
Grade E 16.60 #/ft drill pipe and 300 ft.
of 7” drill collars (2 13/16” ID) for a bitgenerated torque of 1,000 ft-lbf. Assume
that the motor has the same properties
as the 7” drill collars. Shear modules of
steel, G = 11.5*106 psi.
2. What would be the total angle change if
7,300 ft. of drill pipe were used?
28
Solution to Problem 4
From Equation 8.56,
ML
ML
ML
M
GJ motor GJ BHA GJ drillstring
(
)
(
)
4
4
for Pipe, J
OD ID
4.5 4 3.826 4 19.22 in4
32
32
(
)
4
for Collars, J
7 2.813 4 229.6 in4
32
29
Solution to Problem 4, cont.
M L
L
M
G J collars J pipe
in
1,000 ft.lbs 12
ft
lbf
11.5 10 2
in
radians
300 12in 3,650 12 in
4
4
19.22 in
229.6 in
0.001043 15.68 2,278.88 2.394 radians
180 deg
2.394 rad
137.2o
rad
30
Solution to Problem 4, cont.
If Length of drillpipe = 7,300 ft.,
M = 0.001043 15.68+2*2278.88]
= 4.77 radians *
M 273.3
o
180 deg
rad
~ 3/4 revolution!
137.2
31
Example 8.10
Design a kickoff for the wellbore in Fig. 8.35.
e = S48W = 228o
eN = N53W = 307o
a = 2o
L = 150 ft
aN = 6o
De = 79o
Find b, g and d
o
From Ouija Board, b 5.8 , g 97
o
32
New
Direction
Where to Set the Tool Face
o
b 5.8
o
g 97
High
Side
Present Direction
High
Side
Fig. 8.36: Solution for Example 8.10.
33
Dogleg Severity
From Equation 8.43
the dogleg severity,
b
5 .8
d
(i)
100
L
150
d 3.87 / 100 feet
o
34
o
o
With jetting bit: 325
345
o
M = 20
o
307
Fig. 8.36:
Solution
for
Example
8.10.
o
228
35
Tool Face
Setting
New
Direction
High
Side
Where to Set the Tool Face
Compensating for Reverse
Torque of the Motor
Present
Direction
High
Side
Fig. 8.36: Solution for Example 8.10.
36