Page 291 - Fundamentals of Reservoir Engineering

OILWELL TESTING 228

SHUT-IN TIME - ∆t MINUTES 2 3 4 5 6 7 9 1000

7
9
6
3
2
5
4
7
6
100
9
5
2
10
4
3
10
-4
2
3
4
5
6
7
T/F = 500,000
9
10
-3
T/F = 250,000
2
3
4
T/F = 100,000
5
6
7
9
T/F = 50,000
10
-2
2
T/F = 25,000
3
4
5
6
7
9
10
-1
A
∆
∆
∆
V
F
G
T
q
∆t
c W
2
=
=
∆p = p ws
µ
kh
PRESSURE BUILDUP GROUP - ∆ p f / q
A
G
3
- p wf

5.6 c W
4
5
6
= Shut-in time, minutes
T/F = 500
= Wellbore volume, bbls
9
pressure, psi
0
Wellbore Transmissibility,
= Wellbore liquid gradient, psi/ft
cp
; For partially liquid filled wells
= Wellbore fluid compressibility, (psi) -1
mD - ft
= Wellbore cross-sectional, area, sq ft
2
T/F = 100
= Production rate, reservoir barrels per day
V; For completely fluid-filled wells
= Pressure change from flowing
3
4
5
6
7
9
10
1
21
Fig. 7.40 10 7 McKinley type curves for 1 min <∆ ∆∆ ∆t < 1000 min. (After McKinley ) T/F = 250
(Reproduced by courtesy of the SPE of the AIME)