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

8

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

PIPELINE CONSTRUCTION ROW

ROW Grading/Leveling Trenching

Transportation of Pre-coated Pipes to Site

String of Pipes in ROW

PIPELINE CONSTRUCTION

Lowering of the Pipeline

PIPELINE CONSTRUCTION

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 .

The Driving Force For Corrosion

14th & 15th Mar-2013PIM ERPL27

Corrosion basics

Electrolyte

14th & 15th Mar-2013PIM ERPL28

AnodeCathode

Metallic path

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

PIPE LINE COATINGS

3 LPE (2 to 3.5mm thk)

DFBE (0.7mm thk)FBE (0.45mm thk)

3 LPP (2 to 3.5mm thk)

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 

Cathodic Protection Station

Monitoring Cathodic Protection System

Weekly Monitoring the CP parameters.

Quarterly PSP survey at each TLPs

Regular Monitoring the power availability & working of CP units.

PSP profile

Field Coating/Refurbishment CoatingCoal Tar Enamel CoatingHot Applied Coal Tar Enamel TapeCold Applied TapePolyurethanes coatingEpoxy Coatings

Pipeline Rehab. Coatings

Pipeline Rehab. Coatings - Coaltar based Tape