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Integrity of cross country pipelines including Cathodic
protection
INDIANOIL CORPORATION LIMITED (PIPELINES DIVISION)
ALOK SAHOOSenior Operations Manager
Paradip –Haldia-Barauni Pipe Line, Haldia
PIPELINES – THE ENERGY HIGHWAYS
Why Pipeline ?Stationary carrier
No deadweight movement
Environment friendly
Safe and cost effective
Continuous and assured
supply in large volumes
Reduces strain on
rail/road traffic.
Assured delivery of
quality product
Oil Pipelines Network in India
MumbaiVizag
Panipat
Guwahati
Koyali
Nahorkatiya
Haldia
Mathura
Manmad
Vijayawada
Kochi
Barauni
Kanpur
Bhatinda
Kandla
Vadinar
Chaksu
Ahmedabad
Jalandhar
Jodhpur
BudgeBudge
Kot
Delhi
BongaigaonSiliguri
Meerut
Sidhpur
Digboi
Tinsukia
Karur
Chennai
MumbaiHigh
Uran
Ankleshwar
Navagam
TundlaLucknow
Mangalore Bangalore
Secunderabad
Indore
Sanganer
Pune
Maurigram
Rajbandh
NajibabadRoorkee
Ambala
Sangrur
Rewari
Ajmer
Chittaurgarh
Dahej
Coimbatore
Sankari Asanur
Trichy
Madurai
Paradip
Mundra
ProductCrude Oil
IOC’s Pipelines (Existing)
ProductCrude Oil
IOC’s Pipelines (On-going)
Jamnagar
Loni Shahjahanpur
Hazira
JagdishpurNumaligarh
Ratlam
PakniHazarwadi
Other Companies’ Pipelines(Existing)
ProductCrude OilLPG
Mumbai
Vizag
Panipat
Guwahati
Haldia
Vijayawada
Kochi
Kanpur
Kandla
Jalandhar
Delhi Digboi
Secunderabad
Ajmer
Paradip
Jamnagar
Loni
LPG PIPELINES
Barauni
Nabha
Budge-Budge
Trichy
Allahabad
Jaipur
Tikrikalan
Koyali
Sanand
Existing Pipelines (IOCL)Proposed Pipelines (IOCL)
Legend
Durgapur
Chennai
Patan
Existing Pipelines (Others)Existing Bottling Plant (IOCL)
Bongaigaon
Bangalore
Bhopal
Pune
Jamshedpur
Akola
Leh
Jammu
Mathura
EnnoreChenglepetSalem
Erode
Patna
Manmad
Ujjain
Rourkela Balasore
Belgaon
LNG
Existing
Transmission PipelinesExisting
Upcoming
GAIL’s Planned PipelineRIL’s East West PipelineRIL’s Planned PipelineGSPC’s Planned Pipeline
City Gas/ CNGExistingPlanned
LNG Terminal
Total Length = 11360 (Approx.)
JAGDISHPUR
PHOOLPUR
BHATINDA
BAREILLY
DISPUR
DELHI
AGARTALA
BARODA
LUCKNOW
PATNA
AHMEDABAD
RAJKOT
KOTA
MATHANIA
GWALIOR
UJJAIN
AGRA
KOLKATA
GAYA
BOKARO
VARANASIJHANSI
DAHEJ10 mmtpa*
HAZIRA2.5
mmtpa
COIMBTORE
MUMBAI
BHUBANESHWAR
KRISHNAPATNAM
NELLORE
CHENNAI
TUTICORIN
TIRUCHCHIRAPALLI
HASAN BANGLORE
KOLHAPUR
SOLAPURKAKINADA
VIJAYAWADA
DAMRA
DABHOL5 mmtpa
KANJIKKOD
AURAIYA
GOA
CUTTACK
VIJAYPUR
KANPUR
NANGAL
GURGAUN
PUNE
BHARUCH
SURAT
HYDERABAD
RAJAMUNDRY
BHOPAL
KOCHI5 mmtpa
ENNORE2.5 mmtpa
BARMER
MUNDRA6.5 mmtpa
Network of Gas Pipelines in India
OUR ASSETS
About 2,200 employees
Pipeline network having total length of 11,221 km, comprisingpipelines of sizes ranging from 8” to 48” dia and 77.258 MMTPAcapacity
80 stations
14 Windmills (21 MW)
5 Single Point Mooring systems
Around 4.8 Million KL Crude Oil tankage
Dedicated Telecom (with over 6,500 km OFC), SCADA system
CROSS -COUNTRY PIPELINE CONSTITUENTS
LINE PIPECOATING SYSTEMBLOCK VALVEREPEATER CUM CATHODIC PROTECTION STATIONSMARKERSCROSSINGSCOMMUNICATION SYSTEMSCADA
Age Profile of IndianOil’s Existing Pipelines
1800 km(> 40 Years)
2000 km(25-40 Years)
2500 km(10-25 Years)
5000 km(<10 Years)
Threats to Pipeline Integrity
10
Wash Out Seam Failures
PilferageSabotage
Mechanical damage
Gouge marks
Corrosion
Classifying Integrity ThreatsPotential threats
Time dependent
External corrosion
Internal corrosion
Stress corrosion cracking
Stable
Manufacturing defects
Welding / fabrication
defects
Time independent
Third party / mechanical
damage
Operational errors
Act of God
CAUSES OF PIPELINE FAILURE
THIRD PARTY
33%
MECHANICAL FAILURE30%
CORROSION27 %
NATURAL4%
OPERATIONAL ERROR6%
Consequences of Pipeline Threats
Consequence of threats
Environmental
ReceptorsSpill
volume
Loss of image
Dispersion
Product Hazard
Business interruption
Integrity Management Practices in Indian Oil
i) Design Phase
ii) Construction phaseiii) Operation phase
Integrity Management Practices in Indian Oil
Design Phase
Selection of pipeline route
Material selection for main line pipe and pipe fittings
Design & lay out of station and mainline, crossing by HDD
Selection of proper coating
Providing effective CP system
Safety factor during design
Safety system in major equipment
Assessing the environmental and external factors causing risks
Integrity Management Practices in Indian Oil
Construction Phase
Proper Inspection
Monitoring Workmanship
Inspection, surveys & testings like Hydrostatic test etc
Integrity Management Practices in Indian OilOperation Phase
Line Patrolling/ROW Inspection
Inspection of Mainline Facilities/ crossings
Controlling External corrosion
• Monitoring and maintenance of CP system
• Rehabilitation of pipeline coatings
Controlling Internal corrosion
• By injection of corrosion Inhibitor
• Regular pigging of pipelines
Monitoring of Line Parameters
Condition Monitoring of Pipelines (Pipeline surveys )
What is Corrosion ?Loss of metal due to its interaction with environment.Corrosion is an electrochemical process.The corrosion is a complex process which depends on so many factors such as physical ,chemical, metallurgical, electrochemical and thermodynamics .
TYPES OF CORROSION CELLS ON PIPELINE
DISSIMILAR METAL CORROSIONCORROSION DUE TO DISIMILAR SOILDIFFERENTIAL AERATION CORROSION CELL NEW & OLD PIPE
Corrosion can also occur due to
Difference in aeration (crevice corrosion)Contact with a foreign bodyDue to stress (stress corrosion), e.g., mild steel in alkaline environment
Control of CorrosionCoatingCathodic protection- Impressed Current Cathodic Protection- Galvanic Protection
Corrosion inhibitors
Coatings Employed in IOCL PipelinesMa
i
n
l i
ne
Coat i
ngs
Old Pipelines : Coal Tar Enamel
Three Layer Polyethylene -1995
Fusion Bonded Epoxy (FBE)- 2000
Dual Fusion Bonded Epoxy (DFBE) 2006
I. Over the ditch coating :- Old pipelines laid upto 80s, are having over the ditch CTE coating.
II. Plant Coating :- Since the mid 90’s, plant / yard coating is being adopted for new Pipelines.
III. Experience of yard / plant coatingControlled condition for applicationGood surface cleaning due to shot blastingBetter inspection and testingLess current requirement for CP
Pipeline Coatings – Application methods
Cathodic ProtectionA TECHNIQUE TO REDUCE THE CORROSION OF A METAL SURFACE BY MAKING THAT SURFACE THE CATHODE OF AN ELECTROCHEMICAL CELL
Corrosion takes place at the anode only !
Anode: the electrode from which current leaves to the electrolyteAnode gets corrodedCathode: the electrode where current is collected from the electrolyteNo corrosion takes place at the cathode
Mitigation Of External Corrosion in Pipelines:
Cathodic Protection (CP)
By providing CP system, Pipeline Corrosion effectivelymitigated by altering the electrochemical condition.CP achieved by reversing natural corrosion currentwith the supply of current from external source.The external current supply in CP system is generatedeither by sacrificial anode or impressed currentsystem.
Anode
Protected Pipe Pipe
CP unit
Anode Cable
Cathode Cable
TYPICAL CP UNIT
+
‐
Ground bed
Anodic Area
Monitoring Cathodic Protection System
Weekly Monitoring the CP parameters.
Quarterly PSP survey at each TLPs
Regular Monitoring the power availability & working of CP units.
Field Coating/Refurbishment CoatingCoal Tar Enamel CoatingHot Applied Coal Tar Enamel TapeCold Applied TapePolyurethanes coatingEpoxy Coatings
Pipeline Rehab. Coatings