Extreme Hard Rock Perforating: Penetration Challenges and Limits

Extreme Hard Rock Perforating:
Penetration Challenges and Limits
Hanaey Ibrahim
Mohd Shafie Jumaat
Brenden Grove
David Atwood
2012 International Perforating Symposium
IPS 12 04
IPS-12-04
Agenda
1.
2
2.
3.
4.
5
5.
6.
7.
8.
9.
2
Introduction
P f ti P
Perforating
Penetration
t ti Model
M d l & Ch
Challenges
ll
The Cores
Test Procedure
UCS Scratch Test Result
Test Setup
The Tests
Results
Observations
2
Introduction

Khulud field in Oman has deep vertical 4.5” monobore wells drilled for tight gas. Multistage hydraulic fracturing performed.

Rock strength = ~20,000 psi to ~55,000 psi

Porosity + ~5%, K = ~1 mD

Formation breakdown has been a problem.

SPE-152458 for Khulud: Explosive perforating
and abrasive jetting perforating used. Lower
breakdown pressure achieved with abrasive
jetting by average 1180psi.

Need to understand explosive
p
pperforatingg
performance in very strong rock.
3
4
5
Perforating Modeling & Challenges
Charge-A Trend
Charge-B Trend

Khulud formations in Oman with UCS in the range 20,000 to 50,000psi .What is the performance ?
6
Penetration Lower Limit

To confirm the penetration lower limit (DoPmin) proposed in SPE-151846

Khulud cores UCS range
7
The Cores

5 x 1m cores from the following wells were sent to laboratory for perforating shot tests:
Khulud-5
Box #
22
35
11
Top depth
4791.16
4831.7
4886.2
Bottom depth
4792.16
4832.7
4887.2
Core #
2
3
5
Top depth
5083 3
5083.3
5100
Bottom depth
5084 3
5084.3
5101
Core #
2
3
Khulud-6
Box #
17
14
8
Test Procedure

UCS Scratch Test

Cut cores into 8” samples based on
measured UCS

Select the samples to use for the proposed
explosive charge

Shoot the samples in API-19B Section 2
Setup

Retrieve the shot core, cut and measure the
penetration
9
UCS Scratch Test Result ( Core 5-2)
10
UCS Scratch Test Result ( Core 5-3)
11
UCS Scratch Test Result ( Core 5-5)
12
UCS Scratch Test Result ( Core 6-2)
13
UCS Scratch Test Result ( Core 6-3)
14
UCS Scratch Test vs UCS Core Plug Test
Plug UCS Vs. Scratch UCS
g
Sample
ID
Taken From
Core #
Dry Bulk
Densityy
Effective
Compressive
Strength
g
P‐P‐1
P‐P‐2
P‐PL‐1
P‐PL‐2
S‐P‐1
S‐P‐2
S‐PL‐1
S‐PL‐2
U‐P‐1
U‐P‐2
U‐PL‐1
U‐PL‐2
V‐P‐1
V‐PL‐1
Z‐P‐1
Z‐PL‐1
KHDL 5‐5
KHDL 5‐5
KHDL 5‐5
KHDL 5‐5
KHDL 5‐2
KHDL 5‐2
KHDL 5‐2
KHDL 5‐2
KHDL 6‐2
KHDL 6‐2
KHDL 6‐2
KHDL 6‐2
KHDL 6‐3
KHDL 6‐3
KHDL 5‐3
KHDL 5‐3
2.660
2.654
2.653
2.660
2.591
2.585
2.551
2.593
2.594
2.599
2.594
2.599
2.610
2.594
2.614
2.620
31520
28920
24410
26505
32345
29450
27880
31325
22275
29380
24805
37510
32535
32330
(Note 1)
52360
(1)
Quasi‐Static
Young's
Modulus
Quasi‐Static
Poisson's
Ratio
5817500
5701700
5761600
5096600
5624100
5925000
6033100
5488300
3504500
5088600
4816800
5999000
5617300
5249600
(Note 1)
8536400
0.26
0.35
0.14
0.16
0.22
0.25
0.31
0.25
0.21
0.09
0.30
0.20
0.21
0.21
(Note 1)
0.13
Approximate
Scratch UCS
From Same
Location
30 ksi to 34 ksi
30 ksi to 34 ksi
30 ksi to 40 ksi
30 ksi to 40 ksi
25 ksi to 31 ksi
25 ksi to 31 ksi
25 ksi to 30 ksi
35 ksi to 42 ksi
28 ksi
25 ksi to 29 ksi
53 ksi
This sample "failed" the UCS test apparatus being used, when the sample exploded at a load
that would indicate a UCS in excess of 60 ksi. 15
Fbi from UCS and Stress (SPE-151846)

UCS range from the cores for the tests: 20,000 to 50,000psi
16
Cores Segmentation
17
Test Setup

API-19B Section 2 Test

Apply 10,000 radial and confinement stress

0 pore pressure with residual pore fluid

Standard end-cap with cement sheath

Standard gun carrier with scallop and 0.5
0.5”
water standoff
18
The Tests

2 7/8” guns Ch
2-7/8”
Charge-A
A
19
The Tests

2 7/8” gun charge-B
2-7/8”
h
B
20
The Tests

3 5” gun Ch
3.5”
Charge-C
C
21
The Tests

3 3/8” gun charge-D
3-3/8”
h
D
22
The Tests

2” gun charge-E
h
E
23
Test Results
T t
Test
S
Sample ID
l ID
S
Source
Number
Number
Well Core
1
One
KLD5‐2
2
Nine
KLD5‐5
3
Six
KLD5‐3
4
Three
KLD5 2
KLD5‐2
5
Ten
KLD5‐5
6
Seven
KLD5‐3
7
Eighteen
KLD6‐2
8
Five
KLD5‐3
9
Seventeen
KLD6‐2
KLD6
2
10
Seven (back end)
KLD5‐5
11
Ten (back end)
KLD5‐3
12
Thirteen
KLD6‐3
13
Fourteen
KLD6‐3
14
Four
KLD5‐2
Scratch UCS
O
Over Perforated P f t d
Interval
22.6 ksi
42.7 ksi
31.4 ksi
22 5 ksi
22.5 ksi
38.7 ksi
28.7 ksi
29.7 ksi
27.7 ksi
41 0 ksi
41.0 ksi
28.6 ksi
32.8 ksi
22.0 ksi
25.2 ksi
27.6 ksi
24
Shaped
Ch
Charge
To Shoot
2‐7/8" Charge‐A
2‐7/8" Charge‐A
2‐7/8" Charge‐A
2 7/8" Charge‐B
2‐7/8
Charge B
2‐7/8" Charge‐B
2‐7/8" Charge‐B
3.5" Charge‐C
3.5" Charge‐C
3 5" Charge
3.5
Charge‐C
C
2" Charge‐E
2" Charge‐E
3‐3/8" Charge‐D
3‐3/8" Charge‐D
2" Charge‐E
g
W t
Water
Clearance
0.5
0.5
0.5
05
0.5
0.5
0.5
0.5
0.5
05
0.5
0.5
0.5
0.5
0.5
0.5
R k
Rock
Penetration
4.75
4.00
4.00
3 25
3.25
2.75
2.75
4.62
6.00
5 12
5.12
2.75
3.00
6.00
5.88
3.50
Comments
T to B
T to B
B to T
T to B
T to B
T to B
T to B
T to B
T to B
T to B
T to B
T to B; using remains of core from Test 6
B to T; using remains of core from Test 5
B to T
B to T
T to B Observation-1

The penetration does not diminish towards zero, confirming the asymptote (DoPmin)
25
Observation-2

Crossover of Charge-A vs Charge-B based on extrapolation of experimental data at
UCS<20,000 psi does not occur.
26
Observation-3

3-3/8” gun Charge-D matches the performance of 3.5” gun Charge-C at high UCS.
27
Observation-4

2” gun Charge-E matches the performance of 2-7/8” gun Charge-B at high UCS.
28
Way Forward

Charge-A has deeper penetration than Charge-B in the test:


For hydraulic fracturing in Khulud field: trial will be done in 3 wells to see if that is beneficial.
Based on these characterization, these 5 charges can be selected for Khulud
(completion size) and other fields depending on:


Rock strength

Application ( normal unstimulated completion or pre-stimulation
pre stimulation perforating)
PDO Charge A trials:

Two wells have been perforated using Charge A and production logging interpretation is on going
for evaluation.

Third well will be perforated this week using charges A and B followed by acid stimulation and
PLT to measure charge A performance.
29