Corrosion & Inspection
Mari Daharki Field
Asset Integrity Report – 2021
CONTENTS
1- Purpose
2- Executive Summary
3- MPCL Daharki Overview
4- Reservoir Composition
5- Mari Field Assets
5.1 – Wells
5.2 – Processing Facilities
5.3 – Junctions/Manifolds
5.4 – MPCL Gas Gathering Network
6- Damage Mechanisms (HRL, SML, PKL & Goru-B)
7- Corrosion & Inspection Control Framework
8- Work Plan 2021
9- Leak History
10- HSE Highlights
11- Asset Integrity Campaigns
11.1 - LRUT
11.1.1 – Survey Results
11.2 – Thickness Survey
11.2.1 – A scanning/ UFD Assessments
11.2.2 – A scanning Results
11.2.3 – Thickness Mapping Campaigns
11.3 – ECDA
11.4 – Cathodic Protection
11.4.1 – New Solar Based CP System Installation
11.4.2 – Third Party CP System Assessment
11.5 – Risk Based Inspection Study
11.6 – MDCPF ATA
11.7 – MDCPF Storage Tanks A & B
11.8 – Root Cause Failure Analysis
11.9 – Pipeline Pigging
11.10 – Inspection of Storage Tanks & Vessels
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Asset Integrity Report – 2021
11.11 – Kill Lines Survey
11.12 – Exposed Pipeline Survey
11.13 – Piping Supports Survey
11.14 – Pipeline Bell Holes Inspection Survey
11.15 – Underground Pipeline Accessibility Survey
11.16 – Pipeline Cellars Survey
11.17 – Well Casings Integrity Survey
11.18 – Isolation Gasket Survey
12- Circadian Activities
12.1 – Corrosion Inhibitor Injection
12.2 – C scan Survey
12.3 – Weight Loss Coupons
12.4 – Electrical Resistance Probes
12.5 – Pipe to Soil Potential Survey
12.6 – Holiday Detection
12.7 – Positive Material Identification
12.8 – Water Sampling
13- Asset Integrity Services To Satellite Fields
14- Challenges
15- Major Planned Activities FY: 2022~23
16- System Advancement Proposals
List of Figures
Figure-1: Well Formations
Figure-2: Reservoirs Composition
Figure-3: Daharki Field Assets
Figure-4: Leak History Of Previous 4 Decades
Figure-5: Leak History of 2021
Figure-6: HSE Tool Box Talk
Figure-7: LRUT Activity
Figure-8: Thickness Monitoring Activity
Figure-9: A-scanning Activity
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Asset Integrity Report – 2021
Figure-10: ECDA Activity
Figure-11: Anode Boring Activity
Figure-12: RBI Matrix
Figure-13: TEG Dehydration Unit
Figure-14: MDCPF Condensate Storage Tank A & B
Figure-15: Pipeline Pigging
Figure-16: Vessels & Tanks Inspections
Figure-17: Kill Lines
Figure-18: Exposed Pipelines
Figure-19: Piping Support Survey
Figure-20: Pipeline Bell Hole Inspection
Figure-21: Underground Pipeline Accessibility Survey
Figure-22: Well Casing Integrity
Figure-23: Isolation Gaskets
Figure-24: Corrosion Inhibitor Injection Deep
Figure-25: C-scan Survey
Figure-26: Weight Loss Coupons
Figure-27: ER Probe Data Recording Activity
Figure-28: PSP Data Recording Activity
Figure-29: Holiday Detection
Figure-30: Positive Material Identification
Figure-31: Produced Water Sample Collection & Analysis
Figure-32: Zarghun Field Visit Activities
Figure-33: Koonj Field Visit Activities
List of Graphs
Graph-1: Reservoirs Gas Composition
Graph-2: Corrosion & Inspection Control Framework
Graph-3: Leak History of Previous 4 Decades
Graph-4: Leak History of 2021
Graph-5: LRUT Survey Results
Graph-6: LRUT Phase I Thickness
Graph-7: LRUT Phase I MAWP
Graph-8: LRUT Phase II Thickness
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Asset Integrity Report – 2021
Graph-9: LRUT Phase II MAWP
Graph-10: LRUT Phase III Thickness
Graph-11: LRUT Phase III MAWP
Graph-12: LRUT Phase IV Thickness
Graph-13: LRUT Phase IV MAWP
Graph-14: LRUT Phase V Thickness
Graph-15: LRUT Phase V MAWP
Graph-16: Thickness Survey
Graph-17: A-scanning MAWP Goru-B
Graph-18: A-scanning MAWP CMF-I
Graph-19: A-scanning MAWP CMF-II
Graph-20: A-scanning MAWP Phase I Wells
Graph-21: A-scanning MAWP Phase I KODs
Graph-22: A-scanning MAWP Phase II Wells
Graph-23: A-scanning MAWP Phase II KODs
Graph-24: Pipeline Pigging
Graph-25: Kill Lines Thickness Survey
Graph-26: Corrosion Inhibitor Injection Plan
Graph-27: Weight loss Coupons HRL
Graph-28: Weight loss Coupons SML
Graph-29: Weight loss Coupons Goru-B
Graph-30: Average Corrosion Rate Of Goru-B
Graph-31: Average Corrosion Rate Of Shallow
Graph-32: PSP Reading Of Well 3 To 50
Graph-33: PSP Reading Of Well 50 To 100
Graph-34: PSP Reading Of Wells & Other Assets
Graph-35: PSP Reading Of Deep Wells
Graph-36: PSP Reading Of Other Deep Assets
Graph-37: Produced Water Analysis Trend
List of Tables
Table-1: Daharki Field Wells
Table-2: Processing Facilities
Table-3: Junctions / Manifolds
Table-4: MPCL Gathering Network (Reservoirs)
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Asset Integrity Report – 2021
Table-5: MPCL Gathering Network (Pipeline Sizes)
Table-6: Corrosion Severity Analysis Goru-B
Table-7: Corrosion Severity Analysis HRL
Table-8: Corrosion Severity Analysis SML
Table-9: Corrosion Severity Analysis PKL
Table-10: Work Plan 2021
Table-11: MARI Field Daharki Leaks in 2021
Table-12: LRUT Scope
Table-13: A-scanning Scope
Table-14: A-scan Result Summary
Table-15: External Corrosion Direct Assessment
Table-16: Assets Protected by CP
Table-17: Other Assets Protected by CP
Table-18: New Solar System Installation
Table-19: RBI Locations
Table-20: MDCPF ATA Recommendations
Table-21: Repair Works on Storage Tanks A & B
Table-22: Root Cause Failure Analysis
Table-23: Exposed Pipeline Survey
Table-24: Piping Support Sizes
Table-25: Thickness Data Of Bell Hole Inspection Survey
Table-26: Underground Pipeline Accessibility Survey
Table-24: Pipeline Cellars
Table-25: Isolation Gaskets Required Sizes
Table-26: Isolation Gaskets Locations
Table-27: C-scan Survey Loops
Table-28: Holiday Detection loops
Table-29: AIC Remote Fields Visits
Table-30: Major Planned Activities FY: 22-23
Table-31: System Advancement Proposals
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Asset Integrity Report – 2021
Appendices
Annexure 1: LRUT
Annexure 2: A-scanning
Annexure 3: Thickness Mapping Campaign
Annexure 4: ECDA
Annexure 5: Third Party CP Assessment
Annexure 6: MDCPF ATA Report
Annexure 7: MDCPF Storage Tanks A & B Reports
Annexure 8: Portable Condensate Tanks Inspection Reports
Annexure 9: Kill Lines Survey
Annexure 10: Exposed Pipeline Survey
Annexure 11: Piping Support Survey
Annexure 12: Pipeline Bell Hole Inspection
Annexure 13: Underground Pipeline Accessibility
Annexure 14: Pipeline Cellars Survey
Annexure 15: Well Casing Integrity Survey
Annexure 16: Zarghun Field Visit
Annexure 17: Koonj Field Visit
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Asset Integrity Report – 2021
Acronyms
MPCL: MARI Petroleum Company Limited
PSP: Pipe to Soil Potential
TCF: Trillion Cubic Feet
WLC: Weight Loss Coupons
MMSCFD: Million Standard Cubic Feet per Day
TEG: Tri-ethylene Glycol
BTU: British Thermal Unit
NDT: Non Destructive Technique
MDCPF: MARI Deep Central Processing Facility
SCC: Stress Corrosion Cracking
SVPF: Swing Volume Processing Facility
MPI: Magnetic Particle Inspection
HRL: Habib Rahi Limestone Reservoir
ECT: Eddy Current Testing
SML: Sui Main Limestone
PAUT: Phased Array Ultrasonic Testing
PKL: Pirkoh Limestone Reservoir
CRA liner: Corrosion Resistant Alloy
Deep: Goru-B Reservoir
VBT: Vacuum Box Testing
CMF-I & II: Central Manifold I & II
MFL: Magnetic Flux Leakage
HRL DBN: Debottlenecking Project of HRL Loops
KOD: Knock Out Drum
CP: Cathodic Protection
RCFA: Root Cause Failure Analysis
LRUT: Long Range Ultrasonic Testing
MFD: MARI Field Daharki
UFD: Ultrasonic Flaw Detection
TPI: Third Party Investigation
RBI: Risk Based Inspection
ROW: Right Of Way
ECDA: External Corrosion Direct Assessment
UTG: Ultrasonic Thickness Gauging
CP: Cathodic Protection
SPM: Side Pocket Mandrel
ATA: Annual Turn around
ICDA: Internal Corrosion Direct Assessment
ER probe: Electrical Resistance Probe
ICMS: Integrated Corrosion Management System
C.I: Corrosion Inhibitor
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Asset Integrity Report – 2021
1 - Purpose:
The report gives the insight of Mari Daharki Field Asset Integrity Activities during Year-2021.
2 - Executive Summary:
To ensure the longevity of Mari field, being the back bone of fertilizer industry and key contributor
to the food security of the country, full scale Asset Integrity inspection campaigns were launched for
fixed assets during the year 2021. State of the art inspection tools and assessment methodologies
prevalent in the industry were made part of these campaigns to assess the current health and fitness
for service suitability. These assessments increased the confidence level regarding integrity health of
our assets and delivered extensive baseline data of facilities which would be helpful in future trending
and analysis. In addition, critical repairs and component replacements were advised in light of these
inspections beforehand hence preventing hydrocarbon releases, unplanned downtimes and safety
incidents.
Major activities executed by Corrosion & Inspection section during the year 2021 included
•
Long Range Ultra Sonic Testing of Underground Pipelines and Well Casings
•
Annual Inspection of Processing Facilities in turn around
•
A-Scanning & Visual Inspection of Wellhead Surface & Gathering Facilities
•
External Corrosion Direct Assessment of 12 Production Critical loops
•
Third Party Assessments of Cathodic Protection Systems of Well Casings & Pipelines
•
Risk Based Inspection Pilot Project for 4 Wells, CMF I, II
•
In-house Storage Tanks Inspection, Kill Line Survey, Piping Supports Survey, Pipeline Pigging &
Root Cause Failure Analysis
•
Internal & External Corrosion Monitoring and Mitigation of Well Casings, Pipelines, Vessels and
Storage Tanks
•
Asset Integrity Support Services to Satellite Fields
•
Close liaison with Maintenance & Asset Integrity Team for System Upgradation and Improvement
 In light of above campaigns and in house surveys, significant interventions such as coating
replacement of 10 pipeline loops (19.35 km), Repair of MDCPF TEG Contactor tower,
Replacement of MDCPF Condensate Storage Tanks bottom and Replacement of piping fittings
at MDCPF wellheads were recommended. In addition, multiple upgradation projects like
Pipeline Cellars Uplifting, Piping Supports revamping, Industrial grade painting of piping and
exposed well casings and upgradation of CP system have been conceived on the basis of
inspection results.
 Moreover, green initiatives such as conversion of CP power sources from fuel gas to solar
system were started to make our systems more sustainable, environment friendly and
minimize carbon footprint. The team remained committed to promote and pursue excellence
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Asset Integrity Report – 2021
by maintaining highest standards of Health and Safety which resulted in achieving
approximately 31,000 Safe Man Hours during asset integrity campaign execution phase this
year.
 The upcoming year presents new challenges to the team as we embark upon a new journey
with the vision to consolidate on the achievements of last year. Major projects include
procurement and commissioning of Inspection Data Base Management Software,
Upgradation of Downhole Corrosion Monitoring & Injection System, Static Equipment
Integrity Surveys covering Pressure Vessels and Pipelines and implementation of Asset
Integrity framework in true letter and spirit.
3 - MPCL Daharki Overview
•
MPCL Daharki is the largest Field in terms of remaining gas reserves, daily gas production
(Avg.750 MMSCFD) and covers area of 969.27 sq. km. It is located 74 Km (NE) from Rahim Yar
Khan and 94 Km (SW) from Sukkur City. The field consists of 149 wells, 398.90 km of gathering
pipelines infrastructure and 2 gas processing facilities (MDCPF & SVPF). Mari Field Daharki is a
major contributor in country’s urea production (90% Urea Production of Pakistan) thus ensuring
National food security.
•
The field consists of the following types of assets:




Wells of 4 different reservoirs(HRL , SUL & SML , PKL & Goru-B)
Pipelines
Gathering Manifolds (CMF-I & CMPF-II)
Gas processing facilities(SVPF & MDCPF)
Well Formations:
SUL / SML
Formation
HRL
PKL
Goru-B
2.813" TRSCSSSV
20" Conductor pipe
13-3/8" Casing Shoe
Tubing:
3-1/2", 9.3 ppf, L-80, BTS-8 B x P
7" Liner Top
9-5/8" Casing Shoe
7" Hydraulic Packer
Sui Upper Limestone
(Top @ 1040 m)
7" Permanent Packer
Sui Main Limestone
(Top @ 1120 m)
7" Liner Shoe
s
Total No of Wells Drilled = 7
Formation top PKL = ±500 m
Avg. Production = 7 MMDCFD
Avg. BTU = 731 BTU/SCF
Total No of Wells Drilled = 116
Formation top HRL = ± 700 m
Avg. Production = 650 MMSCFD
Avg. BTU = 736 BTU/SCF
Mari Petroleum Company Limited
PBTD
Total No of Wells Drilled = 10
Formation top SUL / SML= ± 1100 m
Avg. Production = 45 MMSCFD
Avg. BTU = 860 BTU/SCF
Total No of Wells Drilled = 16
Formation top = ± 2600 m
Avg. Production = 57 MMSCFD
Avg. BTU = 530 BTU/SCF
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Asset Integrity Report – 2021
4 - Reservoir Compositions:
Avg. Heating Value: 736 Btu/scf
Avg. Heating Value: 860 Btu/scf
Methane,
82.4%
Methane,
72.0%
Ethane,
0.2%
Carbon
Dioxide
10.0%
Ethane
1.0%
Nitrogen,
17.8%
Nitrogen,
13.6%
SML Gas Composition
HRL Gas Composition
Avg. Heating Value: 545 Btu/scf
Avg. Heating Value: 731 Btu/scf
Nitrogen
11%
Methane,
71.2%
Ethane,
0.0%
Nitrogen,
25.9%
Carbon
Dioxide
10.0%
Carbon
Dioxide
10.0%
Other
1%
Methane
45%
Corbon
Dioxide
41%
Eathane
2%
PKL Gas Composition
Goru-B Gas Composition
Graph: Reservoirs Composition
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Asset Integrity Report – 2021
5 - Daharki Field Assets
MPCL Daharki Field
Wells
Processing Facilities
Pipeline Gathering Network
Junctions/Sub Manifolds
5.1 - Wells
Reservoir Name
No of Wells
HRL
116
SML
10
PKL
07
Goru-B
16
Total Wells
149
5.2 - Processing Facilities
MARI Daharki Field Processing Facilities
1
Mari Deep Processing Facility
2
Swing Volume Processing Facility
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Asset Integrity Report – 2021
5.3 - Junctions & Manifolds
MARI Daharki Field Junctions & Manifolds
HRL
20
PKL
2
Deep
5
Sub Manifolds
4
Manifolds
3
5.4 - MPCL Pipeline Gathering Network
Sr.
Pipeline
1
HRL
264.75
2
SML
38.50
3
PKL
16.87
4
Goru-B
35.66
5
HRL DBN
43.13
Total
398.90 km
Sr.
Pipe Diameter
1
2
3
4
5
6
7
6"
8"
10"
12"
14"
16"
20"
Total
Mari Petroleum Company Limited
Network Length (KMs)
Network Length (KMs)
167.80
106.6
56.9
11.8
11.9
17.0
26.9
398.90 km
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Asset Integrity Report – 2021
6 - Damage Mechanisms (HRL, SML, PKL & Goru-B)
6.1 - Goru-B
The CO2 and H2S enriched gas (37-41 mole % CO2, 10-11ppm H2S) is passing through Mari Deep
flow lines which is can potentially cause both Sweet (CO2) Corrosion & Sour (H2S) Corrosion.CO2
corrosion results when CO2 dissolves in water to form carbonic acid (H2CO3). The acid lowers the
system pH which promotes general corrosion and/or pitting corrosion. Wet H2S corrosion can occur,
if system has even 1ppm of H2S gas which can cause steel blisters and cracking.
Corrosion Severity Analysis – Under API-571 & API-581
CO2 Corrosion
Susceptible Conditions
Mari Deep Conditions
Partial pressure of C02 above 30 psig.
Existing C02 partial pressure is 311 psig.
System pressure above 250 psig.
Temperature below 284F increases the corrosion
process.
pH value 4.5~6 can accelerate corrosion.
Carbon steel and Alloy steel are most affected
materials.
System running pressure is 760psig i.e. 510 psig
above the limit.
System temperature is 77F which is 207F below the
limit.
Existing pH is 4 -5.5
Valve Bodies and piping material is Carbon Steel.
Wet H2S Corrosion
Susceptible Conditions
Carbon steel and Alloy steel are affected materials.
Presence of as little as 1 ppm of H2S is sufficient to
cause Sulfide Stress Corrosion Cracking.
Presence of only 1 ppm of H2S is sufficient to cause
hydrogen charging of steel.
Sulfide Stress Corrosion (SSC) generally occurs
below 180F.
Wet H2S attack is more susceptible, if there is free
water pH<4 with some dissolved H2S present.
Mari Deep Conditions
Piping material is Carbon Steel.
10~13 ppm H2S is present in gas stream.
System temperature is 77F i.e. 103 F less than the
limit.
In Close piping loops pH<4 can be anticipated with
dissolved H2S.
Table-6: Corrosion Severity Analysis Goru-B
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Asset Integrity Report – 2021
6.2 - HRL
It is the largest reservoir of the field with the production of 650MMSCFD Gas composition of this
reservoir has nominal CO2 (mol % 10 CO2).This CO2 dissolves in water to form carbonic acid
(H2CO3). The acid lowers the system pH which promote general corrosion and/or pitting corrosion
and is transferred to customers through flow lines at CMF-I & CMF-II.
Corrosion Severity Analysis – Under API-571 & API-581
CO2 Corrosion
Susceptible Conditions
HRL Conditions
Partial pressure of C02 above 30 psig.
Existing C02 partial pressure is 20 psig.
System running pressure is 200 psig i.e. 40 psig lower
than the limit.
Temperature below 284F increases the corrosion System temperature is 80 F which is 204 F below the
process.
limit.
pH value 4.5~6 can accelerate corrosion.
Existing pH is 6.5-7.5
Carbon steel and Alloy steel are most affected
Valve Bodies and piping material is Carbon Steel.
materials.
System pressure above 250 psig.
Wet H2S Corrosion
Susceptible Conditions
Carbon steel and Alloy steel are affected materials.
Presence of as little as 1 ppm of H2S is sufficient to
cause Sulfide Stress Corrosion Cracking.
Presence of only 1 ppm of H2S is sufficient to cause
hydrogen charging of steel.
Sulfide Stress Corrosion (SSC) generally occurs
below 180F.
Wet H2S attack is more susceptible, if there is free
water pH<4 with some dissolved H2S present.
HRL Conditions
Piping material is Carbon Steel.
0 ppm H2S is present in gas stream.
System temperature is 80 F
Existing pH is 6.5-7.5
Table-7: Corrosion Severity Analysis HRL
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Asset Integrity Report – 2021
6.3 - SML
This reservoir contains both CO2 and H2S (3.7 mol% C & 0-3 ppm H2S) which require greater
precautions. 1ppm of H2S gas is adequate for steel Hydrogen charging causing blisters and cracking.
And CO2 can convert to Carbonic acid on contact with water to produce acidic environment.
Transportation of this gas is done through CMF-I to customers.
Corrosion Severity Analysis – Under API-571 & API-581
CO2 Corrosion
Susceptible Conditions
SML Conditions
Partial pressure of C02 above 30 psig.
Existing C02 partial pressure is 11.84 psig.
System pressure above 250 psig.
Temperature below 284F increases the corrosion
process.
pH value 4.5~6 can accelerate corrosion.
Carbon steel and Alloy steel are most affected
materials.
System running pressure is 320 psig i.e. 70 psig lower
than the limit.
System temperature is 74 F which is 210 F below the
limit.
Existing pH is 6.5-7.5
Valve Bodies and piping material is Carbon Steel.
Wet H2S Corrosion
Susceptible Conditions
Carbon steel and Alloy steel are affected materials.
Presence of as little as 1 ppm of H2S is sufficient to
cause Sulfide Stress Corrosion Cracking.
Presence of only 1 ppm of H2S is sufficient to cause
hydrogen charging of steel.
Sulfide Stress Corrosion (SSC) generally occurs
below 180F.
Wet H2S attack is more susceptible, if there is free
water pH<4 with some dissolved H2S present.
SML Conditions
Piping material is Carbon Steel.
(0.0 -3.0) ppm H2S is present in gas stream.
System temperature is 74F
Existing pH is 6.5-7.5
Table-8: Corrosion Severity Analysis SML
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Asset Integrity Report – 2021
6.4 - PKL
Like all other shallow wells this reservoir’s gas is also transported to customers through CMF-II
facility and its gas contains 0 ppm H2S and 5.4 mol % CO2.
Corrosion Severity Analysis – Under API-571 & API-581
CO2 Corrosion
Susceptible Conditions
Partial pressure of C02 above 30 psig.
System pressure above 250 psig.
PKL Conditions
Existing C02 partial pressure is 9.18 psig.
System running pressure is 170 psig i.e. 70 psig lower
than the limit.
System temperature is 70 F which is 214F below the
limit.
Existing pH is 7-7.5
Temperature below 284F increases the corrosion
process.
pH value 4.5~6 can accelerate corrosion.
Carbon steel and Alloy steel are most affected
Valve Bodies and piping material is Carbon Steel.
materials.
Wet H2S Corrosion
Susceptible Conditions
PKL Conditions
Carbon steel and Alloy steel are affected materials. Piping material is Carbon Steel.
Presence of as little as 1 ppm of H2S is sufficient to
cause Sulfide Stress Corrosion Cracking.
0 ppm H2S is present in gas stream.
Presence of only 1 ppm of H2S is sufficient to
cause hydrogen charging of steel.
Sulfide Stress Corrosion (SSC) generally occurs
System temperature is 70F
below 180F.
Wet H2S attack is more susceptible, if there is free
pH is 7-7.5
water pH<4 with some dissolved H2S present.
Table-9: Corrosion Severity Analysis PKL
* Apart from CO2 and H2S Microbiologically influenced corrosion (MIC) is a threat that is prone to
cause damage in the gathering network of all reservoirs. The same aspect has also been highlighted
by the third party during RBI study.
7 - Corrosion and Inspection Control Framework:
Owing to the aging assets, corrosion monitoring and mitigation is utmost need of hour to extend the
useful life of existing assets. Modern researches have resulted in development of availability various
corrosion control tools and methodologies which are extremely beneficial for the successful
operation of gas pipelines even under high corrosive environment.
Although, Mari Daharki field’s process fluid composition and conditions are favorable to produce
CO2 and Wet H2S corrosion, relevant API & NACE guidelines have successfully been implemented to
counter the corrosion menace with cautious monitoring. Pipeline corrosion assessment history also
unfolds that corrosion phenomenon has successfully been arrested by executing the following
corrosion control framework
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Asset Integrity Report – 2021
Corrosion and Inspection Control Framework
Corrosion Management
System
AICs to remote fields
Inspection/AICs
Internal Corrosion
Control
In-house Inspection
Well Casing Integrity
Third Party Inspection
LRUT
Tanks & Vessels Inspection
RBI
Pipeline Cellars Survey
A-scan
Isolation Gasket Survey
ECDA
Pipe Support Survey
CP Assessment
Exposed Pipeline Survey
MDCPF ATA
Root Cause Failure Analysis
MDCPF Storage tank
A&B
Kill lines Survey
External Corrosion
Control
Monitoring
Plan
Control Plan
Monitoring
Plan
Control Plan
Weight Loss Coupons
(WLCs) Analysis
Pipeline
Pigging
Coating C-scan
Survey
PSP data Analysis
Electrical Resistance
(ER) Probes
Corrosion
Inhibitor (CI)
Injection
Pipe to Soil
Potential Survey
(PSP)
Water Sampling
Soil Resistivity
Survey
Iron Counts
RCI Monitoring
Thickness Mapping
Campaigns
Holiday Detection
Thickness Data
Analysis
CP system & Solar
System Revamping
TEG maintenance
Solar System Installation
Gaskets
maintenance
Pipeline Bell-hole inspection
Survey
Corrosion Logging
report Analysis
Underground Pipeline
Accessibility Survey
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Asset Integrity Report – 2021
8 - Work Plan 2021
Corrosion & Inspection Section
Frequency
Locations
Thickness Surveys*:
Annually
Annually
Annually
1 Thickness Monitoring of Deep Pipelines
2 Thickness Monitoring of Shallow Pipelines
3 Thickness Monitoring of Tanks
08 X Wells
40 wells per year
19 X Tanks
Hardness Surveys:
1 Hardness survey of Deep Pipelines & Shallow Pipeline
ER Probes Data Recording:
1 ER Probes data recording of Mari Deep
2 ER Probes data recording of Shallow
Weight Loss Coupons Analysis:
1 Weight Loss Coupons analysis of Mari Deep
2 Weight Loss Coupons analysis of Shallow
Pipe - To - Soil Potential Surveys:
1
All Wells Casings & Pipelines
On Requirement
Monthly
Monthly
09 X Locations
136 X Locations
Bi Annually
Bi Annually
09 X Locations
70 X Locations
Quarterly
01-149 X Wells
02-CMF-I & CMF-II
03-MDCPF Plant
04-Turbine
05-Nara Canal
Quarterly
01-149 X Wells
02-CMF-I & CMF-II
03-MDCPF Plant
04-Turbine
TEG Maintenance & Repair:
1
All installed TEGs
Corrosion Inhibitor Injection:
All Wells Casings & Pipelines
After 22-24 Days
Pipeline Pigging:
1 Pipelines pigging is performed as per plan & the availability of pipelines.
1
149 X Wells
Soil Resistivity Survey:
1
Soil resistivity survey is performed as per requirement.
Assets Integrity Campaigns:
1
A-Scanning/UFD Services for 100 x HRL, 08 x Deep Wells 16 x Junctions /
Manifolds & above ground piping at CMF-I & II
30-Jun-22
2
LRUT Survey
01-233 Underground Pipelines Loops
02-54 X Canal Crossings
03-150 X Risers
04- 67 Well Surface Casings
30-Jun-22
10-April to 31st -December-2021
5
ECDA Survey of 12 Production Critical Pipeline Loops
Cathodic Protection System Performance Assessment Survey at Mari Field
Daharki
25 Solar Powered System Installations
6
96 Isolation Gaskets Installation
5-Apr-22
7
CP Post Installation at 66 X Locations
10-Jan-21
8
RBI of CMF-I, CMF-II, Well-12, SMl-01, PKl-01 & MD-02
15-Feb-22
9
Asset Integrity Campains of Remote Fields
Jan, Feb & August
3
4
11-June to 20-August-2021
28-Apr-21
*Thickness Survey frequency shall be revised according to RBI outcomes.
Mari Petroleum Company Limited
Page 19
Asset Integrity Report – 2021
9 - Leakage History
Mari Daharki Field -Historical Leak Trend 1982 to 2020
- Data is Based on Departmental Information
- No Formal Leak Report is available
6
5
5
NO OF LEAKS
4
4
4
3 3
3
3
No Leakage Records Available
3
3
3
2
2
2
2
2
1
1
1
1
1
1
1
0
0 0
YEAR
1983
0
0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0
0
0
2019
2017
2015
2013
2011
2009
2007
2005
2003
2001
1999
1997
1995
1993
1991
1989
1987
1985
YEAR
Leaks in 2021
Leaks History - Year 2021
6
5
5
No. of Leaks
4
4
3
2
2
2
2
1
1
1
1
0
0
January
February
March
April
May
July
August November December
Months
Mari Petroleum Company Limited
Page 20
Asset Integrity Report – 2021
Mari Field Daharki Leak Events - 2021
Sr.
#
1
Descriptions
Locations
1/2 inch
line
CMF-I Leakage of 1/2 inch line
2
TEG Reboiler
3
Instrument gas package regulator
Nozzle
CMF-I
MDCPF
Plant
MD-06 to
MD-14
Date
Month
5-Jan-21
Nos. of
Leak
1
January
30-Jan-21
1
2-Feb-21
1
February
4
2" Flare-weld Access Fitting Assembly on 20”
pipeline
2" Fitting
W-17
6-Feb-21
1
5
Well head piping
6" CS/SS
Portion
MD-09
6-Mar-21
1
6
Condensate Storage Tank-A
Tank
MDCPF
Plant
7-Mar-21
1
7
8” Bypass meter run of M/s Engro Fertilizers
Limited
CMF-I
10-Mar-21
1
8
Well No.04 pipeline leakage
Well # 04
24-Mar-21
1
9
Upstream elbow of KOD
W-95
9-Apr-21
8" Pipeline
6" Elbow
March
1
April
10
KOD Water drain line leakage
Well # 65
25-Apr-21
11
Gas pipeline leakage
Colony
31-May-21
May
1
12
Condensate Storage Tank-B
Tank
MDCPF
Plant
28-Jul-21
July
1
13
Bhittai-3 to Well-04 (Tie-In JCT-221 Pipeline),
Approx. 1740 Meter, 6-Inches (WT: 5.02 mm)
6" Pipeline
Near W88
26-Aug-21
August
1
14
Drain Line
8" pipeline
MDCPF
Plant
3-Nov-21
15
Glycol Absorber PSV Nozzle
1" Nozzles
CMF-II
8-Nov-21
16
Water Disposal Well
2" Pipeline
CMF-II
11-Nov-21
1
17
Bhittai-3 Tank Leakage
Tank
Bhittai-3
19-Nov-21
1
18
Bhittai-1 Tank leakage
Pipeline
Bhittai-1
22-Nov-21
1
Total Nos. of Leaks
1
1
November
1
18
10 - HSE Highlights
Extensive Asset Integrity Campaigns were launched in the past year for evaluation of Aging Physical
Assets with the aim to maintain continuity of operations, increased assets availability, Reduction in
Safety and Environmental Hazards from leaks and compliance with statutory and corporate HSE
requirements. All activities were carried out with utmost regard of prevailing MPCL safety policies
and resulted in approximately 31,000 safe man hours.
Mari Petroleum Company Limited
Page 21
Asset Integrity Report – 2021
Safety Talk Session
11 - Asset Integrity Campaigns
11.1 - LRUT
A ring of transducers is fitted around the pipeline and the transducers generate and receive low
frequency ultrasonic guided waves along the pipe. The returning echoes indicate defects such as
corrosion and other abnormalities. This method therefore saves time and money that would
otherwise be spent on excavation at extended span of pipelines, coating inspection and recoating.
LRUT Activity
LRUT Shallow Well Casing
Coating brittleness / cracks observed
LRUT Scope
Phase I to X underground Pipelines (233 loops)
67 Well Surface Casings
54 Canal Crossings
150 risers
Mari Petroleum Company Limited
Page 22
Asset Integrity Report – 2021
•
•
•
•
•
Sample based LRUT is under way @ 2 to 3 shots per KMs,
114/233 pipeline segments have been completed.
Phase-1 ~ 5 & well casing reports have been submitted by M/s SGS.
Phase-6 Pipelines & Risers Scanning is underway.
Phase-7 and onwards is to be completed by June 2022
11.1.1 - Survey Results
Phase 1-3
•MAWP > Operating pressure. Pipelines are safe to operate at current parameters.
•Pipeline coating condition were found satisfactory at all bell holes locations.
•Coating damaged and disbondment issues were observed at exposed pipeline sections e.g. inside
water courses/ cellars and near canal banks.
•MAWP > Operating pressure. Pipelines are safe to operate at current parameters.
•Coating replacement suggested for 04 X pipelines loops cumulative length ~ 13 KMs.
•Pitting observed in 9 feet span of 6” Pipeline from CMF-I to CMF-II. Replacement of defective
portion mandated in light of LRUT results.
•Results on the basis of C-scan survey Partial Coating Repair shall be planned for multiple pipelines
of around 1400 m.
Phase-4
•MAWP > Operating pressure. Pipelines are safe to operate at current parameters.
•Coating replacement suggested for 02 X pipeline loops cumulative length ~ 4.95 KMs.
Phase-5
•No significant metal loss recorded.
•Paint Flaking/Deterioration, Corrosion / rusting & short bolting were observed.
•Interseal 670HS Black (OEM :Akzonobel) is selected as protective coating for Wellhead surface
Well Casings casings.
Phase I Results (1965)
Thickness
10
8
6
7.11
6.95
4
7.11
6.83
8.18
8.18
8.18
8.18
8.18
4.48
4.98
4.94
4.91
4.88
3
4
5
6
7
2
0
1
2
Original Thickness [mm]
Mari Petroleum Company Limited
Actual Thickness [mm]
Page 23
Asset Integrity Report – 2021
MAWP
1500
1000
1011
990
435
500
345
345
335
503
325
498
325
494
320
490
235
1
2
3
4
5
6
7
0
Operating Pressure [ Psig]
MAWP [Psig] After Deducting Corrosion Allowance = 1 mm
Phase II Results (1977)
Thickness
10
7.11
8
7.11
6
7.11
6.18
4
6.11
6.95
2
3
9.27
9.27
8.28
8.37
4
5
2
0
1
Original Thickness [mm]
Actual Thickness [mm]
MAWP
Operating Pressure [ Psig]
MAWP [Psig] After Deducting Corrosion Allowance = 1 mm
1500
1000
500
871
859
360
330
1
2
1009
758
768
335
325
325
3
4
5
0
Mari Petroleum Company Limited
Page 24
Asset Integrity Report – 2021
Phase III Results (1981)
Thickness
10
7.11
7.11
8
6
6.11
4
7.11
6.03
7.11
6.05
3
4
8.18
6.78
8.18
6.81
5
6
9.27
8.16
9.27
8.44
9.27
8.47
7
8
9
6.08
2
0
1
2
Original Thickness [mm]
Actual Thickness [mm]
MAWP
1000
857
800
852
843
846
360
320
320
744
748
744
775
315
315
310
778
600
400
335
390
200
390
0
1
2
3
Operating Pressure [ psig]
4
5
6
7
8
MAWP [Psig] After Deducting Corrosion Allowance = 1 mm
9
Phase IV Results (1985)
Thickness Results
10
8
6
4
2
0
1
3
5
7
9
11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41
Origional Thickness [mm]
Mari Petroleum Company Limited
Actual Thickness [mm]
Page 25
Asset Integrity Report – 2021
MAWP
1200
1000
Cellar Location
800
600
400
200
0
1
3
5
7
9
11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41
Operating Pressure [ Psig]
MAWP [Psig] After Deducting Corrosion Allowance = 1mm
Phase V Results (1993)
Thickness Results
10
8
6
4
2
0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
Origional Thickness [mm]
Actual Thickness [mm]
MAWP
1200
1000
800
600
400
200
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
Operating Pressure [ Psig]
MAWP [Psig] After Deducting Corrosion Allowance = 1mm
Outcomes Of LRUT: [Refer Annexure 1, for further details]
•
Phase: 1-5 pipelines are safe to operate at current parameters.
•
19.35 KMs coating replacement recommendation for 10 pipeline loops
Mari Petroleum Company Limited
Page 26
Asset Integrity Report – 2021
11.2 - Thickness Surveys
Thickness monitoring is an effective mean to identify the “As Is” condition of assets by trending the
average metal loss over period of time. Thickness monitoring of Mari Daharki Deep is being carried
out on “Yearly Basis” using in house resources.
Thickness Trend of Deep Wells For 2021
4
3.6
3.6
3.4
3.5
2.88
3
2.6
2.5
2.3
2.15
2
1.7
1.5
1
0.5
0
Maximum Thickness Loss (mm)
1 MD-02
2 MD-03
3 MD-04
4 MD-06
5 MD-09
6 MD-12
7 MD-14
8 MD-15
Thickness Monitoring Activity
11.2.1 - A scanning/UFD Assessment
M/s Velosi performed the fitness for service assessment as per API 570 of Well Head piping at MPCL
Daharki Gas Field to carry out a detailed condition evaluation and remaining life assessment of Well
Head piping. Detailed inspection of piping system included
Mari Petroleum Company Limited
Page 27
Asset Integrity Report – 2021
Scope of Work for A-scanning
Above ground piping at CMF-I & CMF-II
HRL X 100 Wells
Deep X 08 Wells
Junctions / Manifolds X 16
Sr.
Description
Scanned Percentage %
01
02
03
04
05
06
Well Piping (HAZ area of Weld Joints 4” to 6”)
KODs Shell:
KODs Nozzles:
Fittings [ Elbows , Tees, Bends ]
Dead legs:
By pass Lines:
07
Drain Valves:
Locations
Results Summary
•
CMF-1 & 2
100%
20%(at suspected locations)
100%
100%
100%
100%
A-Scanning /UFD to possible extent, at
suspected corrosion prone areas
MAWP (Maximum Allowable Working Pressure) greater than MOP (Maximum
Operating Pressure) at all scanned locations
MAWP (Maximum Allowable Working Pressure) greater than MOP (Maximum
•
Operating Pressure) at all scanned locations
Deep
Phase I & II
•
Localized Metal loss observed at multiple fittings on Mari Deep-02, 04, 09,14
•
Replacement of 22 fittings recommended based upon A-Scan results
•
Safe to operate at current parameters based on acquired thickness data
•
Proper paint cleaning repair, bolting, degraded supports replacing/repairing and
gauges calibration to be done
Phase III & onwards
•
Scanning of wells is under progress (93% completed)
•
Reports are under review and will be shared soon
11.2.2 - A scanning Results [Refer Annexure 2, for further details]
MAWP Analysis Goru-B
MAWP
1205
Pressure (Psi)
1500
1000
904
782
750
Operating Pressure
1134
750
1068
907
979
750
750
750
MD-12
MD-14
MD-15
767
750
750
MD-04
MD-06
750
500
0
MD-02
MD-03
MD-09
Well Location
Mari Petroleum Company Limited
Page 28
Asset Integrity Report – 2021
MAWP Analysis CMF-I
1175
1139
1290
1348
1356
875
699
240
240
240
240
240
240
240
PIPING CIRCUTS
(12"FFCIII BYPASS
METER RUN )
HEADERS 1
HEADERS 2
HEADERS 3
KOD -1
KOD -4
KOD -5
Operating Pressure PSI
MAWP [Psig] After Deducting Corrosion Allowance = 1 mm
MAWP Analysis CMF-II
1272
1274
1275
965
956
240
240
240
240
240
240
PIPING (10" EFL-II
1BYPASS METER RUN)
HEADERS 1
HEADERS 2
KOD-7
KOD-8
KOD-9
734
Operating Pressure [Psig]
MAWP [Psig] After Deducting Corrosion Allowance = 1 mm
Phase I Wells & KODs
MAWP Analysis of Well Piping
MAWP Analysis of KODs
2500
919
838
839
823
2061
2000
1500
1637
1635
729
656
2025
1307
1313
1000
295
253
260
240
281
270
500
295
253
260
240
281
270
0
WELL-03 WELL-04 WELL-05 WELL-06 WELL-08 WELL-09
Well-03
KOD
Well-04
KOD
Well-05
KOD
Well-06
KOD
Well-08
KOD
Well-09
KOD
Operating Pressure PSI
MAWP [Psig] After Deducting Corrosion Allowance = 1
mm
Mari Petroleum Company Limited
Operating Pressure (Psig)
Page 29
Asset Integrity Report – 2021
Phase II Wells & KODs
MAWP Analysis of KODs
MAWP Analysis of Well Piping
2000
1601 1617 1620 1618 1666
1608
978
895
944
876
949
975
805
786
1355
1500
1507
1000
285
264
262
266
254
269
246
246
500
285
264
262
266 254
269
246 246
0
WELL-10WELL-11WELL-12WELL-13WELL-14WELL-15WELL-16WELL-17
Well-10 KOD Well-12 KOD Well-14 KOD Well-16 KOD
Operating Pressure PSI
Operating Pressure (Psig)
MAWP [Psig] After Deducting Corrosion Allowance = 1 mm
MAWP [Psig] After Deducting Corrosion Allowance = 1 mm
A-scanning Activity
11.2.3 – Thickness Mapping Campaigns [Refer Annexure 3 for further details]
Thickness mapping campaign comprising of the following was conducted:
•
•
•
•
2 x condensate Storage Tanks & 3 x produced water tanks at CMF II
Fire Water Network CMF-I & II
Three Phase Separator
Portable Oil & Water Tank
Campaign Results:
•
•
•
•
Baseline Thickness data were recorded. (Storage Tanks)
Pin holes, Severe Pitting / metal chip off were observed. (Fire Water Network)
Internal Protective coating was found disbonded. (Three Phase Separator)
Incomplete welding, Rusting / pitting & no internal coating were observed. (Portable Oil &
Water Tank)
Mari Petroleum Company Limited
Page 30
Asset Integrity Report – 2021
11.3 – External Corrosion Direct Assessment
ECDA as per (NACE standard SP0502) was performed by SGS for 12 Production Critical Pipelines
(Headers) of Daharki field transporting approximately 600 MMSCFD of natural gas.
Sr. #
Pipeline Description
Pipeline
Size
(Inches)
Length
(KM)
Gas Flow Rate
(MMSCFD)
Defects
detected
during
DCVG
1
Junction-204- Junction-317- CMF-I
20
7
155
12
2
Junction-317 To CMF-II
20
3
80
6
3
Junction-204- Junction-317
16
3.6
30
5
4
CMF-I To CMF-II
16
0.7
5
CMF-I To CMF-II
16
0.7
6
Junction-515 To CMF-II
16
11
100
7
7
Well-14 To CMF-I
12
3.7
22
9
8
Junction-11 To Junction-317
10
2.6
75
8
9
Junction-107 To CMF-I
10
2
55
0
10
Well-14 To Junction-107
8
2
40
1
11
MD-14 To MDCPF
12
1.9
24
7
12
MD-9 To MDCPF
8
4
8
11
Total Number of Defects
50
0
0
66
* Site Activity (except for 1 location due to local issues) has been completed and the report is under
review and will be shared in February 2022.
General Observations: [Refer Annexure 4 for further details]
•
Uncoated patches were detected during inspection.
•
Pipeline coating damaged was observed.
•
Rusting / Pitting was observed at uncoated portion
•
Metal loss observed at 05 x locations.
ECDA Activity
Mari Petroleum Company Limited
Page 31
Asset Integrity Report – 2021
11.4 - Cathodic Protection
Cathodic protection is achieved by passing enough direct current electricity from an external source
(a more powerful anode), which could be a galvanic anode or an impressed current anode. CP system
deployed at MFD protects an extensive network comprising of the following:
CP system Dharki Field
Sr.#
1
Assets
Underground pipeline network
2
3
4
HRL Well casings
SML Well casing
PKL Well casings
5
Goru-B Well casings
Status
Protected
Length/Number
398.9 km
Protected
Protected
Protected
Protected
Not Protected
116
10
8
5
3
Other Assets Protected by CP
1
2
3
4
5
6
7
8
9
10
11
CMF-II piping
NCWGL
Nara Canal
Colony 2" Gas Line
Colony 3" Gas Line
Colony 6" Gas Line
Colony 8" Gas Line
MDCPF Plant Piping
MDCPF Condensate TANK-A & B
Fire Water Network
Fire Water Tank
Anode Boring Activity
11.4.1 - New Solar Based CP System Installation
Due to favorable conditions of environment and green initiative of the company solar system are
being used and Third Party assessment is underway on the field. A total of 25 wells were shifted to
solar energy in the year 2021.
Wells Powered By Solar Energy In 2021
Sr.#
Reservoir name
Well names
1
HRL
Well-102 to Well-120 & Watayo-01 (19 wells)
2
SML
Shaheen-01,02, Bhitai-02, 05 & Shahbaz-01 (6 wells)
Total Number of Wells
Mari Petroleum Company Limited
25
Page 32
Asset Integrity Report – 2021
11.4.2 – Third Party CP system Assessment
A third party assessment was conducted for determining condition of existing CP systems. Initial
findings of the assessment confirm that in-placed CP System is fully effective as per NACE guidelines.
However, assessment report is under review and will be shared by mid of February 2022.In light of
recommendations and gap analysis findings, following activities are planned to be performed in
2022[Refer Annexure 5 for further details]


E log I survey of well casings to determine current requirement as per NACE RP0186
Increase/replacement of anodes as per current requirements of well casings

Upgradation of Current Control/ Anode junction boxes

Drafting of CP system As-built drawings

Installation of Isolation gaskets

Tagging of Cable connection and Junction boxes
* Cathodic Protection system of GTH is being planned by P&E department.
11.5 – Risk Based Inspection Study
RBI is an integrated methodology that reviews prevailing inspection techniques and frequencies
consequently leading to optimized inspection strategies based upon risk analysis. M/s SGS has carried
out RBI study at the following locations in the year 2021.The report of this study is yet to be shared
by the third party.
RBI Study Locations
Sr. #
1
2
3
4
5
Reservoir
Well
CMF-I & II
HRL
SML
PKL
Goru-B
Well-12
SML-01
PKL-01
MD-02
RBI Matrix
Mari Petroleum Company Limited
Page 33
Asset Integrity Report – 2021
11.6 - MDCPF ATA Inspections
Inspection of Glycol Dehydration Unit including TEG contactor Tower, TEG Reboiler, Stripping
Column, Reflux Coil, TEG Flash Tank, Three Phase Test Separator A & B, TEG Reboiler Surge Tank and
TEG Lean Rich Heat Exchanger was carried out from 1st to 4th April 2021.
Scope of Work:
Following Inspections and NDT techniques were used for assessment and evaluation
• Internal visual inspection of TEG Contactor Tower, TEG Flash Tank, TEG Reboiler, TEG Surge Tank
and Three Phase Test Separators
• External visual inspection of all equipment for assessment of any imperfections and defects in
relating to service like cuts, cracks, gouges, pits, corrosion, SCC and deterioration of insulation and
susceptibility of any CUI (corrosion under insulation) due to ingress of moisture.
• UTG of TEG Contactor Tower, TEG Flash Tank, TEG Reboiler, TEG Surge Tank and Three Phase Test
Separator A & B for determination of any thickness loss.
• DPT of Nozzle connections and selected Tee sections on TEG Contactor, TEG Flash Tank and TEG
Surge Tank for determination of any surface discontinuity like (Pin holes, cracks, under cuts etc.).
• MPI was performed on selected Tee sections of TEG Reboiler and associated nozzle openings for
assessment of any surface and near surface defects.
• Hardness testing of welds was performed on TEG Surge Tank and TEG Reboiler for assessment of
metallurgical changes due to long term exposure with Process stream temperature.
• ECT of Lean Rich Heat Exchanger tubes for evaluation of thickness loss.
• Acoustic Emission testing of Lean Rich Heat Exchanger tubes for evaluation of thickness loss
Recommendations: [Refer Annexure 6 Report Page # 203 ~ 207 for further details]
Lean Rich Heat Exchanger:
•
•
Considering this inspection as baseline, TEG-Exchanger shall be re-inspected during next TA, to
estimate exact rate of deterioration.
Tubes with 30% wall loss are acceptable as per acceptance criteria.
TEG Gas Contactor:
•
•
•
Damaged CRA liner and Temporary repaired N6A nozzle will be permanently rectified under the
guidelines of API-510 and ASME PCC2.
All 04 nozzles indication shall be evaluated during next turnaround for defects propagation.
Tower will be inspected after “One Year” for assessment of all reported anomalies. Due date for next
inspection will be April-2021.
TEG Surge Tank, TEG Reboiler:
•
•
TEG Surge Tank and TEG Reboiler are made of low corrosion resistance material i.e. A36 [Carbon
Steel]. By replacing the A36 with SS (300 series) material can permanently mitigate consistently
occurring damages.
Both equipments will be inspected after “One Year” for assessment of all reported anomalies. Due
date for next inspection will be April-2021.
Flash Tank, Three Phase Separators:
•
All above equipment’s are declared Fit-For-Service as no significant abnormality observed during
inspection.
Mari Petroleum Company Limited
Page 34
Asset Integrity Report – 2021
•
Calculated due date for next internal inspection is April-2031 however, inspection will be planned in
line with forthcoming ATAs.
General view of vessel
MDCPF Glycol Dehydration Unit
11.7 - MDCPF Storage Tank A & B
Inspection and subsequent repair works of 3000 barrel Condensate Storage tank A and B were carried
out at MDCPF under third party inspection plan in the following dates:
•
•
Tank-A: 14th March to 14th April, 2021
Tank-B: 21st August to 30th October, 2021
Internal coating of both tanks was absent which caused degradation of bottom plates in both these
tanks. Subsequent repair works were initiated for restoration of tanks.
Repair Works Conducted On Each Tank: [Refer Annexure 7 for further details]
Storage Tank-A





Tank Foundation Repair
Complete Bottom Replacement
Addition of Water Draw off Sump and Sump
Nozzle
Internal Coating of Bottom and Shell & Roof
Installation of sacrificial anodes for Internal
CP protection
Storage Tank-B








Mari Petroleum Company Limited
Tank concrete ring wall repair
Replacement of sand cushion underneath
tank bottom
Complete bottom replacement
Addition of water draw off sump and
nozzle
Installation of sacrificial anodes for
Internal CP protection
Replacement of inlet nozzle
Internal Coating of Bottom and Shell &
Roof
Welding of liquid level gauge upper nozzle
and 4 inch foam line nozzle
Page 35
Asset Integrity Report – 2021
MDCPF Condensate Storage Tank A & B
11.8 - Root Cause Failure Analysis
Root Cause Failure Analysis (RCFA) is a systematic way of reviewing all the evidence from a failure in
order to determine a root cause that is manageable and prevent recurrence. Following RCFA were
conducted during the year 2021
RCFA
Sr.
IIR No.
Date of IIR
Description
01
104
26th Aug 2021
2mm pinhole at 6 o clock in 6 ‘’ Bhitai-03 to Well-04( Jct-221 Tie-in pipeline)
02
114
17th Nov 2021
Drain line leakage at MDCPF
03
117
10th Nov 2021
Leakage from Glycol Absorber PSV Nozzle
04
119
11th Nov 2021
Pinhole leakage from injection line of WDW at CMF-II
05
123
19th Nov 2021
Pinhole leakage at Condensate Storage Tank of Bhitai-03
06
124
19th Nov 2021
Minor leakage at 4” header of Liquid storage tank of Bhitai-01
*All leakages were corrected through proper procedures and preventive measures for long term safe
functionality of all such assets were also recommended to management.
11.9 - Pipeline Pigging
Mari flow lines pigging activity is carried out on “Yearly Basis” to displace the accumulated water and
sludge etc. which consequently reduces the corrosion activity inside pipelines. Moreover, corrosion
inhibitor batch treatment is also performed while pigging for effective internal corrosion prevention.
Iron counts of samples gathered during pigging are also measured for gauging the corrosion activity.
Mari Petroleum Company Limited
Page 36
Asset Integrity Report – 2021
Pipeline Pigging Program
HRL Loops
Mari Deep Lines
(17)
(11)
MD Lines
MD Lines
(Completed Loops = 08)
(Remaining Loops = 03)
HRL Shallow Wells Loops
HRL DBN Loops
(Remaining Loops = 15)
(Completed Loops = 02)
Pigging Activity
Challenges
•
Pig Launcher and Pig Receivers are missing at a few locations.
•
Pressure and Temperature Gauges installation and calibration are required at a few locations.
•
Pig Doors / Valves functionality verification is required at certain locations.
•
Pig Signals installation and functionality verification is required at a few areas.
•
Drain Pits formulation is required at a few locations.
11.10 - Inspection of Storage Tanks & Vessels
On the basis of leakage in 50 BBLs condensate storage tank bottom at Bhittai-03 step by step
inspections were in of all condensate storage tanks placed at below mentioned locations along with
4 KODs placed at CMF.
•
•
•
Shaheen-1,
Shaheen-2,
Shahbaz-1,
•
•
•
Mari Petroleum Company Limited
SML-1,
Bhittai-1,
Bhittai-2,
•
•
•
Bhittai-3,
Bhittai-5,
CMF,
•
•
•
Hilal-1,
Iqbal-1,
KOD 7, 8, 9 & 10
Page 37
Asset Integrity Report – 2021
Tanks Inspections
Vessels Inspections
* Shaheen-01, Shaheen-02 and Shahbaz-01 are yet to be inspected under this plan.
The inspection reports comprised of the following:
1. Introduction
2. Background
3. Inspection Techniques
4. Inspection Findings
5. Thickness Results
6. Recommendations
Results:
• Although foreign Debris was found in KOD vessels, the overall condition was satisfactory
• Condensate Storage Tanks had major issues regarding their design and functionality
General Recommendations: [Refer Annexure 8 for further details]
•
•
•
•
•
•
External and internal protective coating after surface preparation to be ensured for storage tanks
Repair /replacement of damaged plates
Proper welding at nozzles and shell to bottom joints
Proper bolting
Sacrificial Anode installation recommended for Internal Cathodic protection of storage tanks
Third Party Investigation shall be done of all condensate storage tanks
11.11 – Kill Lines Survey
In house Kill Line Inspection Campaign was carried out at 81 well locations. Following aspects
were covered and became the basis of recommendations:
1-1- Thickness
Thickness Profile
Profile
2-2- Gaskets
conditions
Gasket Conditions
3- Line supports condition
Mari Petroleum Company Limited
4- Coating condition for buried lengths
5- Paint condition for surface lengths
6- Housekeeping related matters
Page 38
Asset Integrity Report – 2021
[Refer Annexure 9 for further details]
Kill Lines Survey
*Planning and Execution Department is working on the revamping mentioned in this survey.
11.12 – Exposed Pipelines Survey:
Exposed Pipelines survey was conducted in Jan-Feb 2021, to identify the locations where pipelines
are exposed and prone to damage at HRL, SML, Goru-B ROWs. [Refer Annexure 10 for further details]
Total pipeline length accumulated to 12 km and the activity comprised of the following
•
•
•
Protection of all exposed pipeline sections by proper excavation, lowering and backfilling
operation.
Acquisition of pipeline integrity data of “Thickness Profile” and “Coating Condition”.
Exposed pipeline sections inspection and rectification.
Mari Petroleum Company Limited
Page 39
Asset Integrity Report – 2021
Exposed Pipeline Survey
Sr. #
1
2
3
4
5
6
7
Pipeline size (inches)
6
8
10
12
14
16
20
Number of lines exposed
26
17
5
2
1
1
1
Well # 99 - Tie-in Main line 10" at Well # 79 to Jct.515) (6'' Exposed Pipeline Section)
Well # 98- Tie-in Main line 10"at Well # 79 to Jct.515 (6'' Exposed Pipeline Section)
*80 % of the highlighted pipelines through this survey have been revamped till now.
11.13 - Piping Supports Survey:
In the backdrop of Well-4 gas leak which occurred on September 15th, 2019 at 8” pipeline
coming from Junction-133 to Junction- 204, a comprehensive pipeline supports inspection
survey was carried out to avoid the reoccurrence of similar leakages. Production Shallow Pipeline
Junction Pipe Supports and Production Shallow & Deep Pipeline Support assessment survey was
conducted.
Summary: [Refer Annexure 11, for further details]
Piping Supports Found Damaged = 218.
Piping Supports Foundation Damaged = 166.
Mari Petroleum Company Limited
Page 40
Asset Integrity Report – 2021
Location Well-17 JCT 117
Location Well-23
* Planning and Execution Department is working on the revamping mentioned in this survey.
11.14 - Pipeline Bell Holes Inspection Survey
Utilizing the in-house resources thickness and coating wrapping condition of flow lines was inspected
before the commencement of LRUT of the whole field [Refer Annexure 12 for further details]
Thickness monitoring
Pipe Surface after Coating Removal
Bell Holes Inspection Thickness Results
Phase I
(6-inch Pipeline)
Well-05 to JCT-105
Well-03 to Well-08
Thickness Loss ( mm)
Bell hole-1
Bell hole-2
Bell hole-1
Bell hole-2
Bell hole-3
Bell hole-4
(8-inch Pipeline)
Well-09 to Well-16
Mari Petroleum Company Limited
0.35
0.36
-0.35
-0.17
-0.20
-0.22
Thickness Loss ( mm)
Bell hole-1
Bell hole-2
Bell hole-3
Bell hole-4
3.35
3.34
3.27
3.34
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Asset Integrity Report – 2021
Well-08 to Well-15 to CMF-1
Bell hole-5
Bare Pipe L-1 (W-55)
Bare Pipe L-2 (W-55)
Bell hole-6
Bell hole-7
Bare Pipe (W-97)
Bell hole-8
Bell hole-9
Bell hole-10
Bell hole-1
Bell hole-2
Bell hole-3
Bell hole-4
Bell hole-5
Bell hole-6
Bell hole-7
Bell hole-8
Bell hole-9
3.34
3.34
3.33
3.37
3.40
3.35
3.31
3.32
3.29
3.40
3.37
3.31
3.38
3.35
3.38
3.38
3.34
3.36
Phase II
(6-inch Pipeline)
Well-23 to Well-14
Thickness Loss ( mm)
Bell hole-1
Bell hole-2
Bell hole-3
Bell hole-4
Bell hole-5
0.67
0.97
0.90
0.95
1.06
Phase III
(6-inch Pipeline)
Well-20 to Well-53
Thickness Loss ( mm)
Bell hole-1
Bell hole-2
0.86
0.78
11.15 - Underground Pipeline Accessibility Survey
Pipeline Accessibility survey was conducted earlier in Feb 2021, to identify the locations where
pipelines are inaccessible owing to encroachment issues, sand dunes, cultivated lands and
unavailability of ROW etc. which could result in possible hindrance to perform Inspection &
Maintenance activities.
Objectives of the activity are listed below:
•
•
•
•
All encroachments can be removed
Lines can be made accessible in sand dunes and cultivated land
New ROWs can be prepared at inaccessible locations
Line rerouting can be planned / executed where needed
Mari Petroleum Company Limited
Page 42
Asset Integrity Report – 2021
[Refer Annexure 13 for further details]
Sr.#
Summary Of Findings
Locations
1
Total No. of "Land Encroachment Locations"
163
2
Total No. of Locations Where "Pipelines Passing Through Cultivated Lands"
210
3
Total No. of Locations Where "Pipelines Passing Through Sand dunes"
86
4
Total No. of Locations Where "No ROW Availability"
11
5
Total No. of Locations Which are "Not Approachable"
4
*29 % progress has been made till now by the land department.
11.16 - Pipeline Cellars Survey
A complete survey of cellars at Daharki field wells was performed to assess the condition of pipeline
in cellars, and take rectifying measures to prevent any incident that could disrupt the pipeline
operations. A comprehensive plan comprising of both Production shallow wells and Production Deep
wells was derived. [Refer Annexure 14 for further details]
Sr. #
Types of
Cellars
1
Cellars
containing
Pipelines
2
Cellars at
MDCPF.
3
Cellars with
ER Probe.
Quantity
Action Plan and Responsibilities
15
13
Renovation
2
Backfill
4
4
Renovation
0
Backfill
21
4
Cellars with
Valves.
5
Cellars with
Valves and
ER probe.
18
Renovation
52
Renovation
3
Backfill
52
0
Backfill
6
6
Renovation
0
Backfill



House Keeping of Cellars. (Corrosion team)
Coating/Painting of Pipeline in the Cellar.
(Corrosion Team)
Backfill of Cellar. (Field Maintenance)


Housekeeping of Cellars. (Production Deep).
Coating/Painting of Pipeline. (Corrosion Team)



House Keeping of Cellars. (Corrosion team)
Coating/Painting of Pipeline in the Cellar.
(Corrosion Team)
Backfill of Cellar. (Field Maintenance)


Housekeeping of Cellar. (Production Shallow)
Coating/Painting of Pipeline.(Corrosion Team)


Housekeeping of Cellar. (Corrosion Team)
Coating/Painting of Pipeline. (Corrosion Team)
*The comprehensive rectification and uplifting plan has been developed in the light of “Cellars
Survey”, “Kill lines Survey”, and “Piping Support Survey”. Maintenance Static, Corrosion and
Inspection along with Head Office Planning and Engineering department are jointly working on these
projects. These restoration projects are under way.
Mari Petroleum Company Limited
Page 43
Asset Integrity Report – 2021
11.17 - Well Casing Integrity Survey
Integrity was ascertained of 66 wells by visual inspection of Casing pipe and conductor pipe (where accessible)
and measuring thickness of conductor pipe at multiple locations.
Recommendations: [Refer Annexure 15 for further details]
•
Assets external surface to be painted periodically with industrial grade paints after proper surface
preparation.
•
Wellhead pits / cellars will be made waterproof.
•
Regular removing of water from pits to be ensured.
•
Conductor pipe and surface casing documents shall be shared for effective analysis.
Before
After
Before
After
Before
After
Mari Petroleum Company Limited
Page 44
Asset Integrity Report – 2021
11.18 - Isolation Gaskets Survey
Flange Isolation Gaskets provide an effective seal and electrical isolation of flanges. Gaskets are an
integral component of CP system and are beneficial in following ways
•
•
•
•
CP system efficiency improvement,
Ground bed life enhancement,
Facilitation during UG pipeline surveys [C-scan, PCM, DCVG etc.],
Protection of Assets from stray currents etc.
Isolation Gasket Required Sizes
4-Inch
6-Inch
8-Inch
10-Inch
12-Inch
14-Inch
16-Inch
20-Inch
0
32
33
10
5
0
6
10
Total Required Gaskets
96
Already installed Gaskets
69
Remaining
27
Gaskets Locations
Planned for without Shutdown
JCT-154
JCT-186
JCT-118
JCT-515
JCT-138
JCT-159
JCT-111
JCT-133
JCT-197
JCT-134
JCT-131,11
JCT-136
Planned with Shutdown
CMF-I
JCT-221
CMF-II
JCT-114
JCT-317
JCT-116
JCT-204
Gasket Conditions
Mari Petroleum Company Limited
Page 45
Asset Integrity Report – 2021
12 - Circadian Activities
12.1 - Corrosion Inhibitor Injection Program:
CI Injection Plan
Non Packer Wells
Packer Wells
In Tubing via Bottles
In Tubing via Pump
(Total Locations: 05)
(Total Location: 01)
In Tubing via
Master Valve
(Total Location: 41)
Through Casing via
Bottles
Through Casing via
Injection Pump
(Total Location: 76)
(Total Location: 05)
In Tubing through
Swab Valve Top
In Tubing through
Wing Valve
(Total Location: 17)
(Total Location: 24)
Deep
M/s Nalco has carried out the comprehensive Chemical Treatment study of Mari Deep gas gathering
network. After performing detailed lab performance analysis, they have recommended to perform
continuous injection of Oil Soluble Inhibitor (EC 1391 A). These pipelines are being constantly treated
by the rate “1 Pint / MMCFD” with 1:4 (Inhibitor: Condensate). Overall protection performance of
said methodology is above “98%”.
Corrosion Inhibitor Injection Skid – Preventive Maintenance
Shallow
Shallow wells of HRL, SML and PKL receive Corrosion Inhibitor in the form of Batch injection.16 gallons
for flow lines and 20 gallons for casings are injected respectively. Frequency of Batch injection in
shallow wells is 24 days.
Mari Petroleum Company Limited
Page 46
Asset Integrity Report – 2021
12.2 - C-scan
C-scan of underground pipeline is done under the guidelines of MSP-FMT-03. The equipment has the
ability to record the data from different locations and to display the graphs between different
properties such as depth cover over pipelines, coating resistance, coating conductance, pipeline
diameter and attenuation revealing the exact locations of holidays to be rectified.
Pipeline Loops C-scanned in 2021
Sr. no
1
2
3
4
5
Loops
Well-06 to Well-16
Well-17 to CMF-II
Well-17 to CMF-II
Shahbaz-1 to Well-04 to Jct-221
Well-15 to Well-06
C-scan Activity
size
10''
20''
20''
6''
8''
Total Length (Km)
length(m)
1478.0
3250.2
3090.7
576.1
2511.2
11.0
C-scan Analysis Graph
12.3 - Weight Loss Coupon Analysis:
Under the guidelines of NACE SP 0775-18, Weight Loss Coupons are being used to analyze the relative
corrosion behavior with “Bi-annual frequency”.
Online weight Loss Coupon Retreival
Mari Petroleum Company Limited
Page 47
Asset Integrity Report – 2021
* 50 % difference between blank Corrosion rates and CI dosage corrosion rates at SML wells during
the 2 mentioned months.
Mari Petroleum Company Limited
Page 48
Asset Integrity Report – 2021
12.4 - Electrical Resistance (ER) Probes Results:
ER Probes data of Daharki field pipelines is being gathered on “Monthly Frequency”. The acquired
data is analyzed to scrutinize the relative corrosion trends for the optimization of corrosion inhibitor
injection program.
ER Probe Data Recording
Average Corrosion Rate (mpy) Of Deep
12" Pipeline from Deep-2,14&15 at MDCPF
10" Pipeline from Deep-3,4&12 at MDCPF
0.105
0.023
8" Pipeline from Deep-01 & 09 at MDCPF
0.373
6" Pipeline from Deep-06 at MDCPF
0.082
8" Pipeline from Deep-15 at Deep-02
10" Pipeline from Deep-2 & 15 at Deep-14
0.117
0.039
8" Pipeline from Deep-3 & 12 at Junction at Deep-13
6" Pipeline from Deep-4 to Junction Deep 13
6" Pipeline from Deep-12 at Deep-03
0.000
0.191
0.057
0.044
0.050
0.100
0.150
0.200
0.250
0.300
0.350
0.400
Avg
ER Probe Data Trend Analysis-2021
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
-0.1
3
5
10
12
14
16
19
26
29
32
35
37
40
42
44
47
50
52
55
57
60
64
67
71
73
75
77
79
81
83
85
87
90
93
95
98
100
102
104
107
109
116
118
120
0
Mari Petroleum Company Limited
Page 49
Asset Integrity Report – 2021
12.5 - PSP Data Recording
Pipe to soil potentials are being measured to gauge the protection level of an underground metallic
structure under cathodic protection. The Protection criteria of a “structure to electrolyte potential”
of -850 mV to -1250 mV as measured with respect to a saturated copper/copper sulphate reference
electrode is sufficient to protect the structure from corrosion.
PSP data recording activity
P S P ( VO LT S ) O F H R L W E L L S 3 TO 5 0
1.6
Fullfills NACE criteria of -850 mV for Cathodic Protection
1.4
1.2
1
0.8
0.6
0.4
0.2
0
3
1.8
1.6
5
8
10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
P S P ( VO LT S ) O F W E L L S 5 0 TO 1 0 0
Fullfills NACE criteria of -850 mV for Cathodic Protection
1.4
1.2
1
0.8
0.6
0.4
0.2
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
67
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
92
93
94
95
97
98
99
100
0
Mari Petroleum Company Limited
Page 50
Asset Integrity Report – 2021
P S P ( VO LT S ) O F W E L L S & OT H E R A S S E T S
Fullfills NACE criteria of -850 mV for Cathodic Protection
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
PSP (Volts) - Piping Deep
1.4
Fullfills NACE criteria of -850 mV for Cathodic Protection
1.2
1
0.8
0.6
0.4
0.2
0
Deep-1
Deep-2
feb
Deep-3
march
Deep-4
april
Deep-6
may
june
Deep-9
July
Deep-12
August
Sept
Deep-13
Deep-14
Oct-Nov
Dec
Deep-15
Other Deep Assets PSP Reading
Fullfills NACE criteria of -850 mV for Cathodic Protection
1.4
1.2
1
0.8
0.6
0.4
0.2
0
MDCPF
Tipu-I
march
Mari Petroleum Company Limited
Tipu-II
april
may
Azadi-1
june
July
MDCPF
Condensate
TANK-A
August
MDCPF
Condensate
TANK-B
Sept
Oct-Nov
Fire Water Tank
Fire Water
Network
Dec
Page 51
Asset Integrity Report – 2021
12.6 – Holiday Detection
Inspection of coating wrapping of pipelines by holiday detection was done at following locations
Holiday Detection Locations
Sr.#
Locations
Size (inch)
1
2
3
4
5
6
7
8
Well # 50 - 09
Well # 30 -Jct.11 (PKL Loops)
Well # 97 to 8 (16-22-50)
Well # 09-Jct-157
Jct-157 - Well 55 Tie-in
Well # 09-Jct-157
Well # 26 -Jct.204
Well # 36 - Jct.134
6
6
6
8
8
8
8
10
Holiday Detection
12.7 – Positive Material Identification (PMI)
Newly acquired tool for Positive Material Identification has been acquired for material verification
and traceability. The tool has been used for following purpose since its procurements
•
•
•
•
MD-02 SS pipeline grade verification
MD-13 to MDCPF pipeline grade verification
Reboiler coil material verification
Verification of MTCs before during inspection of incoming stock at the warehouse
PMI
Mari Petroleum Company Limited
Page 52
Asset Integrity Report – 2021
12.8 - Produced Water Analysis
Samples are collected from 146 wells on monthly basis from both deep and shallow for iron count
and RCI analysis which is used in CI injection rates optimization.
Water sample collection
Lab analysis of collected samples
ER probe / WLCs / Iron Counts Graphical Trend Year 2021
5.00
ER Probe
WLC
4.00
2.00
Corrosion rates (mpy)
3.00
Iron Count
1.00
0.00
Well No.
On the basis of such data collected trends are made for analysis and review of corrosion inhibitor
dosage requirement for these wells.
Mari Petroleum Company Limited
Page 53
Asset Integrity Report – 2021
13 - Asset Integrity Campaigns of Remote Fields
Corrosion & Inspection team of MPCL Daharki field made a total of 3 visits to other satellite fields:
AIC Remote Field Visits In 2021
Sr.#
1
2
3
Visit date
26-30th January 2021
15-18th February 2021
26-30th August 2021
Field name
Zarghun Field
Koonj Field
Zarghun Field
13.1 - Zarghun Field:
Zarghun field was visited by Daharki team twice in the last year. Once in January to perform
inspection activities so that detailed diagnostics could be performed on the increasing frequency of
replacement of inlet Coalescing Filter at ASU.
Second visit was made during August-2021 planned shutdown of Zarghun field.
Activities Performed By Daharki Team in January-2021:
1. Thickness Monitoring Of Pipelines & Equipment
2. Weight Loss Coupons Online Retrieval and Installation
3. Functionality check of ER Probes
4. Visual Inspection of facilities
Recommendations after the Visit: [Refer Annexure 16 for further details]


Locations of ER probes and WLCs were suggested for Corrosion Monitoring of assets
Critical fitting for thickness monitoring was identified and its monitoring frequency was set

Pigging activity and its necessary requirements i.e. Pig launcher and receiver were to be set up
Activities Performed By Daharki Team in August-2021:
1. Pipeline Pigging Activities

Pipeline From ZS2 To Plant

Pipeline From ZS4 To Plant
2. Weight Loss Coupons Replacement Activities
3. ER Probe Data Acquisition and Installation Activities
4. Thickness Monitoring at Selected Locations
Recommendations after the Visit: [Refer Annexure 16 for further details]




Corrosion Inhibitor Injection System to be installed at ZS-03 on priority basis
ZS-03 piping to be re-evaluated with P & E by considering the design and operating philosophy.
ER probe and WLCs locations identified
Inspection Management System to be upgraded to A-Scanning from conventional Ultrasonic Thickness
Gauging (UTG).
Mari Petroleum Company Limited
Page 54
Asset Integrity Report – 2021


Pigging activity facilities that need upgradation were proposed
General Observations of the facility were conveyed
Zarghun Visits Activities
13.2 - Koonj Field:
Daharki team visited Koonj Field in February for integrity assessment of Koonj Field Underground Gas
Transportation Pipeline [6’’ Sch.40; 13 KMs]. The line serves the purpose for gas transmission from
facility to Tie-In assembly.
Inspection Activities Performed:
The buried pipeline was examined by formulation of bell holes at various locations. The following
activities were performed at selected locations:
1234-
Pipeline Cover,
Pipeline Coating Condition,
Pipeline Base Metal Inspection,
Pipeline Thickness Monitoring,
Observations of the Visit: [Refer Annexure 17 for further details]
All above integrity assessment activities reveal that pipeline coating and base metal are in good
condition. Regular monitoring and assessment of all facility assets shall be carried out for
establishment of healthy reliability data.
Koonj Field Visit Activities
Mari Petroleum Company Limited
Page 55
Asset Integrity Report – 2021
14 - Challenges:
1. Although Downhole Assets Corrosion Rates are under control through effective batch treatment
via conventional technique however, advanced tool of SPM (Side-pocket mandrel) need to be
incorporated in future wells for safe chemical injection for well casing and tubing protection.
Suggested Way Forward
SPM technology should be introduced in forthcoming wells by Petroleum Engineering Team.
2. Higher Blank Corrosion Rates recorded at SML wells. Batch Treatment was conducted after 07months that reduced the CRs by 50 %. The downhole injection is indispensable at these critical
locations and deferment of same due to well unavailability can cause serious menace to Well
Integrity.
Suggested Way Forward
Production Team to ensure the Well availability i.e. 2hr/month for effective downhole treatment.
3. Downhole corrosion monitoring along with WLCs and standardized corrosion inhibitor injection at
all well locations is required to check the Batch treatment effectiveness and corrosion rates
calculation.
Suggested Way Forward
MOC for “Corrosion Monitoring System Upgradation” to be expedited on priority basis for timely
completion of project. Presently MOC is under review of P & E Department.
4. Unavailability of As-built drawings.
Suggested Way Forward
Formation of As-built drawings.
5. No design documents available.
Suggested Way Forward
All essential design documents should be developed and accessible to all end users.
6. 1 technician is burdened with handling of injection and maintenance of injection pumps at 131
wells
Suggested Way Forward
Pump maintenance to be transferred to rotary section as per new organogram.
7. Retired manpower resources have not been replaced by new hiring for more than a year now.
Suggested Way Forward
Hiring of skilled resources against retired personnel.
Mari Petroleum Company Limited
Page 56
Asset Integrity Report – 2021
8. Timely resolution of Land and Security Issues pertaining to third party and in-house inspection
activities
Suggested Way Forward
Land and security department should swiftly resolve the land and security issues so that on-sites
activities can be concluded timely.
9. Water Logged Areas are an issue for C & I department while working with sensitive equipment
to obtain on ground readings.
Suggested Way Forward
Although, we are executing the tasks after fulfilling the all pre-requisites. However, above issue is
hampering the AI activities progress and pace.
10. Lack of certification and training plan for the Asset Integrity Team
Suggested Way Forward
Local training budget has also incorporated in OPEX Year-2022~23 budget. Whereas, advance
level trainings have also been incorporated in TNA.
Mari Petroleum Company Limited
Page 57
Asset Integrity Report – 2021
15 - Major Planned Activities FY: 2022~23
Activity
Scope

LRUT Survey
ECDA Survey
(Phase-II)
A Scanning
CP System
Upgradation
Asset Integrity
Inspections
Based upon the results of first phase of survey, 100 LRUT shoots are planned
for critical loops and bends FY 2022-2023

ECDA survey would be extended to 15 more production critical loops in year
2022-2023

A-scanning of critical equipment would be conducted for corrosion mapping

New CP System Installation at 05 Locations

Elog I Assessments of 35 X Well casings

Sacrificial Anode installation for Cathodic Protection for 04 storage tanks

CP System rehabilitation in line with Third Party CP System Assessment Report

Baseline inspection of Swing Volume Compression Facility

Annual inspection of Mari Deep Central Processing Facility

Baseline inspection of 2xCondensate Storage Tanks, 1xFirewater Tank and
1xProduced Water Storage Tank

Corrosion
Monitoring System
Upgradation
Upgradation of downhole corrosion monitoring system for 30 wells is planned
for the year FY 2022-2023. Project will include installation of corrosion
coupons, produced water sampling points and upgradation of inhibitor
injection assemblies.
QA/QC Activities
Management
Asset Integrity
Support To
Satellite Fields
RBI Study – Mari
Daharki Field
Asset Integrity
Software
Implementation

Assurance of QA/QC during TEG contacting tower Liner replacement job.

NDT Testing (DPT, MPI, RT ..) provision for repair and maintenance activities as
per requirement

Inspection of Coating repair activities of underground pipelines

Asset Integrity Support Services like Static Equipment Inspection, Corrosion
Monitoring and Control, Pipeline Pigging and Cathodic Protection System
Assessment etc. on requirement basis.

Risk Based Inspection Study of entire Mari Daharki Field with close
coordination of M & AI

Mari Petroleum Company Limited
Inspection Data Base Management Software selection and
implementation with close coordination of M & AI
Page 58
Asset Integrity Report – 2021
16 - System Advancement Proposals
Sr.
#
01
Proposals
Internal Corrosion Direct
Assessment – ICDA
(Pilot Project : NACE –SP0206)
02
Integrated Corrosion
Management System – ICMS
(Feasibility Study and
Installation Project)
03
Online Leak Detection System
(Feasibility Study and
Installation Project)
Downhole Corrosion Coupons
Assemblies
(Feasibility Study and
Installation Project)
Intelligent Pigging
( For Production Critical Line)
04
05
06
AIMS Implementation - Brown
Fields (Mari Daharki Field)
Mari Petroleum Company Limited
Brief Introduction
Internal Corrosion Direct Assessment (ICDA) is a structured process
that improves safety by assessing and reducing the impact of
internal corrosion on pipeline integrity and is implemented under
the guide lines of NACE - SP0206. The primary goal of the approach
is to determine if internal corrosion is likely or unlikely to exist in a
chosen length of pipe. ICDA standards provide guidelines to
calculate the remaining life of the pipe based on the data collected
in the Direct Examination Step and based on these results it
recommends half of the remaining life as the re-assessment
interval.
The Integrated Corrosion Management System ICMS is the most
comprehensive and powerful online corrosion monitoring system
available. The ICMS corrosion management server is the hub of
the corrosion or erosion monitoring system, integrating several
forms of corrosion monitoring and process data into one complete
online system, shared over a variety of communication links.
Online Leak Detection System shall enable the real time monitoring
of Production Critical and Aged Pipelines. That accelerates the
rectification response time and minimize the HSE risk.
The Downhole Coupon Holder Assembly (DCHA) is developed to
test the effects of different types of corrosion on downhole tube
materials, including general corrosion, crevice corrosion, stress
corrosion, and pitting in downhole conditions.
Intelligent Pigging is an inspection technique whereby an inspection
probe, often referred to as a "smart" pig, is propelled through a
pipeline while gathering important data, such as the presence and
location of corrosion or other irregularities on the inner walls of the
pipe. Intelligent pigs use nondestructive examination techniques
such as ultrasonic testing and magnetic flux leakage testing to
inspect for erosion corrosion, metal loss, pitting, weld anomalies,
and hydrogen induced cracking, among others. They are also able
to gather data on the pipeline's diameter, curvature, bends, and
temperature.
Like GTH AIMs Implementation Project, Third Party should be
engaged for proper implementation of AIMs at Brown Field
(Particularly Mari Daharki Field) so that RAM, RCM, RBI etc. can be
implemented in true letter and spirit.
Page 59