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---

A 30.01.2012 ISSUED FOR INFORMATION O.Y O.Y E.D

Rev.

No. Date Description

Prepared Checked Contr. By Approved ------------

ORIGINATOR Published by

EDOPEC ENERJ PETROL MHENDSLK SANAY VE TCARET LMTEDRKET

Contractor

Document Title

Corrosion Management and Cathodic ProtectionOffice :

PalmiyeMah. Adnanmenderes Bulv. Oktay Sitesi

No: 9/8 PK = 33100 Yeniehir /Mersin TURKEYP:+90 324 3260595

F:+90 324 3260596

Ankara Office :UUR MUMCU CAD(krolucad) ERDL APT87/13 Gop-ankaya -Ankara-TURKYEP: +90 312 447 17 18 / 20

F:+90 312 447 17 21

stanbulOffice:BurhanyeMahalles amlca Caddesihlamurvi llalar no 28 / 6^RD3K Villa ^Beylerbeyi skdar stanbul / TURKEYP : +90 216 4220414 PBX

F: +90 216 4220415

www.edopec.com.info@edopec.com

Document No.

EDO PPP COE COR INT XXX 013 051 052 Rev ACo. Org.

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http://www.edopec.com/mailto:info@edopec.commailto:info@edopec.commailto:info@edopec.comhttp://www.edopec.com/

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Head Office : Palmiye Mah. Adnan menderes Bulv. Oktay Sitesi No: 9/8 PK = 33100 Yeniehir /MersinTURKEYP:+90 324 3260595 F:+90 324 3260596

Ankara Office : UUR MUMCU CAD(Krolu cad) ERDL APT 87/13 Gop-ankaya -Ankara-TURKYEP: +90 312 447 17 18 / 20 F:+90 312 447 17 21

stanbul Office: BURHANIYE MAHALLESI AMLICA CADDES HLAMUR VLLALARI NO 28 / 6 ^^RD 3K VLLA ^^Beylerbeyi skdar STANBUL / TURKEY P : +90 216 4220414 PBX F: +90 216 4220415

EDOPEC ENERJ PETROL MHENDSLK SANAY VE TCARET LMTEDRKET

www.edopec.com. info@edopec.com

Corrosion Management andCathodic Protection

http://www.edopec.com/mailto:info@edopec.commailto:info@edopec.comhttp://www.edopec.com/

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Edopec Corrosion divisions

is organized with a vision of providing engineering services and manufacturing

for Authorities and Clients located in Turkey , Iran , irak Syria and Middle-

east.Libya ,

Our focus is on complete Cathodic Protection services including all of the

Consultation, Survey, Design, production and installation related work for On-shore & Off-shore facilities, Off-shore & Marine inspection and Industrial

Automation for:

Oil and Gas Industries (offshore & onshore)

Petrochemical industry

Energy

Cement industry

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Project

Manger

Procurementbody

QC and Testbody

Logisticcoordinator

TechnicalSupport

Erection Group

Documentation

GroupElectrical

Group

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PROJECT ACTVTES

ACTIVITY DETAILS

ENGINEERING & DESIGN

Direct Assessments Services;

Soil Resistivity Survey, CAT (Current Attenuation Test) Survey, DCVG (Direct Current Voltage/Gradient) Survey, Current

Requirement/Drainage Survey, CIPS (Close Interval Potential) Survey, Stray Current Interference Survey, Polarization and On/Off Potential

Survey, Coating Resistance Survey, Anode bed Resistance Survey, Buried Structures Natural Potential Survey, Overhead line Effect on

Buried Structures Survey, (SRB) Sulphur Reduced Bacteria Survey, pH Survey, Carbonate And Sulphate Ions Survey, Grounding System

Resistance Survey, Internal Cathodic Protection and microbial corrosion monitoring and inspections.

Engineering Design;

Basic & Detailed Design of Cathodic Protection systems for Pipelines, Tank Forms, Petro-Chemical Plates, Power Plants, vessels, harbors,

Jetties, offshore and marine structures by both means of SACP and ICCP system (where applicable) Design of SCADA based ICCP

systems, Design of Stray Current and AC mitigation Systems.

Materials/Equipment Design;

Design and development of various types of CP Trans/rectifier Units, Design and development of Special Power Supply units, Design and

development of RRU systems ( Remote Rectifier Units), Design and development of RMU systems ( Remote Monitoring Units), Design anddevelopment CP Remote Monitoring and Control systems. Design and development of GPS synchronized On/Off control of T/R units,

Design and Development of Current Control boxes, Sacrificial anode design.

PROJECT MANAGEMENT Project management of SCADA based ICCP systems, Project management of ICCP and SACP systems, Project management of Local

Cathodic Protection of Oil and Gas and Energy Facilities.

COMMISSIONING

& START UP

Deepwell and shallow groundbed installations, ICCP systems for Pipelines and Storage Tanks, ICCP systems for Congested area and

Tank Farms, SACP installation for interior surfaces of storage tanks, SCADA based Cathodic Protection systems, CP Remote monitoring and

Control systems, Galvanic CP and ICCP systems for Pipelines, Storage Tanks and Tank Farms, CP systems for Marine Structures and

Offshore Pipelines, Galvanic CP and ICCP systems for Ships, Vessel, Jetties and Piers, Internal Galvanic CP and ICCP systems for Water

Tanks and Boilers, Galvanic CP and ICCP systems for Reinforcing steel in Concrete Structures, SCADA communication systems (Wireless,

Satellite, GSM, Fiber Optics) , Installation and replace of permanent reference electrodes under the tank bottom plate for further potential

monitoring proposes via. horizontal drilling technology.

EQUIPMENT MANUFACTURE Fabrication and production of TR units ICCP anodes, Sacrificial anodes, current control and junction boxes, Coupons and reference

electrodes.

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PRODUCTION and SUPPLY

Item Product

1 Transformer Rectifier Units

2 Test, Junction, Bond Boxes

3 Current Control and Compensation Boxes

4 Reference electrodes and coupons

5 Cables and connections

6 Remote Monitoring System& Software

7 MMO coated Ti anodes

8 Silicon Iron Chromium Anodes

9 Magnesium anodes

10 Zn Anodes

11 Al Anodes

12 Backfill Materials

13 Miscellaneous

14 Cathodic Protection Software

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CATHODIC PROTECTION SYSTEM

SCADA SOFTWARE

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CATHODIC PROTECTION SYSTEM

SCADA SOFTWARE

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CATHODIC PROTECTION RECTIFIER

UNIT

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PRODUCTION and SUPPLY

MAJOR CP SERVICES OFEDOPEC

SITE SURVEYS & INSPECTIONS

SERVICES

ENGINEERING DESIGN, PLANNINGAND R&D SERVICES

INSTALLATION AND COMISSIONING

SERVICES

BACK-UP SERVICES

TRAINING

SITE SURVEYS & INSPECTIONSSERVICESSite surveys are undertaken to evaluate

the corrosion behaviour of different

environments, Cathodic Protectionmonitoring, underwater inspection of

structures, anodes, and coatings ,Earthing and lightning activities by

means of soil, water, location, stray

current and so on testing.

EDOPEC , undertakes the followingsurveys and inspections

Soil Resistivity Survey

CAT (Current Attenuation Test) SurveyDCVG (Direct Current Voltage/Gradient) SurveyCurrent Requirement/Drainage SurveyCIPS (Close Interval Potential) SurveyStray Current Interference SurveyPolarization and On/Off Potential Survey

Coating Resistance SurveyAnode bed Resistance Survey

Buried Structures Natural Potential Survey

Overhead line Effect on Buried Structures Survey(SRB) Sulphur Reduced Bacteria SurveypH Survey

Carbonate And Sulphate Ions SurveyGrounding System Resistance Survey

Contact Voltage (Touch and Step Voltages) SurveyLightning Protection Installation SurveyLightning Protection Level SurveyInternal Cathodic Protection and microbial corrosion monitoringand inspections.

Potential Profile, Current Distribution Survey of Power Plants,

Take-off yards and substations

Sub-sea Platform inspection for maximum deep of 40

meters including repair, wet welding, cutting, anode

inspection ( Cleaning, montage, re-montage,photography)and NDT tests (MPI, FMD, Thicknesstestes)

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BACK-UP SERVICES

EDOPEC . maintains close contact with the market so that it cantailor its product offering to the needs of the clients. The

considerable experience has ensured that the Company can

provide complete back-up services from initial design to final

commissioning and maintenance. The aim is to give customers an

efficient, professional service of the highest quality. Comprehensive

range of maintenance and support services provides a further levelof back up, as appropriate.

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ENGINEERING DESIGN, PLANNING AND R&DSERVICES

The engineering and design phase is one of the key processes during the project execution stage. EDOPEC.

Currently has a core staff of several engineers. All of these have been selected because of their unique alternativeexperience.

We are more than able to provide our clients with the project teams to meet the challenges presented by

mature fields.

Advantages have been successfully involved in almost every advanced engineering project carried out in EDOPEC..Clients have recognised, through the provision of project services, EDOPECs ability to efficiently provide their

requirements.

Basic & Detailed Design of Cathodic Protection systems for Pipelines, Tank Forms, Petro-Chemical Plates, Power Plants,

vessels, harbours, Jetties, offshore and marine structures by both means of Galvanic and ICCP system (where applicable).

Design and development of various types of CP Trans/rectifier UnitsDesign and development of Special Power Supply units

Design and development of RRU systems ( Remote Rectifier Units)

Design and development of RMU systems ( Remote Monitoring Units)

Design and development CP Remote Monitoring and Control Systems

Design and development of GPS synchronized On/Off control of T/R units

Project Design of SCADA based ICCP systems

Project Management of ICCP Galvanic CP systems

Project Design of Local Cathodic Protection of Oil and Gas and Energy Facilities

Design and Planning of CP installation of special ICCP anodes

Design and Planning of Subsea and Offshore Structure CP systemsDesign and Planning of Ships and Vessels ICCP systems

Design and Planning SCADA communication systems

Design and Planning of ICCP Systems for Internal Cathodic Protection

R & D of CP systems of Reinforcing steel in Concrete Structures

R & D on AC interference analysis and mitigation system design

R & D on Projects Safety and Economics

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INSTALLATION AND COMISSIONING SERVICES

Edopec Co. have ability to provide installation and commissioning services for the following projects and systems relevant to

Oil & Gas and Energy Industries.

Deepwell and shallow groundbed installations

ICCP systems for Pipelines and Storage Tanks

ICCP systems for Congested area and Tank Farms

Galvanic CP installation for interior surfaces of storage tanks

SCADA based Cathodic Protection systems

CP Remote monitoring and Control systems

Galvanic CP and ICCP systems for Pipelines, Storage Tanks and Tank Farms

CP systems for Marine Structures and Offshore Pipelines

Galvanic CP and ICCP systems for Ships, Vessel, Jetties and Piers

Internal Galvanic CP and ICCP systems for Water Tanks and Boilers

Galvanic CP and ICCP systems for Reinforcing steel in Concrete Structures

Ribbon anode installation for new constructed storage tanks

ICCP system for existing tanks using horizontal drilling technology.

Installation and replace of permanent reference electrodes under the tank bottom plate

for further potential monitoring proposes via. horizontal drilling technology.

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Fundamentals of Corrosion Corrosion Cell:

Conditions required for corrosion Corrosion Rate Corrosion Types

Commonly Affected Structures Corrosion Control

Materials Selection

Inhibitors/Altering the environment

Coatings

Cathodic Protection Measuring potentials

Criteria

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Fundamentals of Corrosion Corrosion Cell:

Conditions required for corrosion Corrosion Rate Corrosion Types

Commonly Affected Structures Corrosion Control

Materials Selection

Inhibitors/Altering the environment

Coatings

Cathodic Protection Measuring potentials

Criteria

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Introduction to Corrosion

Corrosion can be defined as the deterioration of metal

due to its interaction with the environment. Corrosion

is a natural phenomenon, which should not surprise

one, but rather should be expected to occur. Metals arehigh energy materials, which exist because heat energy

was added to natural iron ores during the smelting

process. Nature, by environmental contact, constantly

attacks these high energy materials and breaks themdown to the natural elements from which they were

derived.

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Conditions Required for

Corrosion

Corrosion is an electrochemical process occurring atthe interface between metal and environment. Threeconditions must be present for this to occur.

1. Two areas on a structure or two structures mustdiffer in electrical potential.

2. Those areas, called anodes and cathodes, must beelectrically interconnected.

3. Those areas must be exposed to a commonelectrolyte (soil or water).

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Those areas must be exposed to

a common electrolyte

CURRENTFLOW

CURRENT FLOW

IONIZED ELECTROLYTE

WIRE

ANODE(IRON)

CATHODE(COPPER)

CURRENT FLOW

(- TO + IN ELECTROLYTE)

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Those areas must be exposed to a

common electrolyte

CURRENTFLOW

CURRENT FLOW

IONIZED ELECTROLYTE

WIRE

ANODE(IRON)CATHODE(COPPER)

CURRENT FLOW

(- TO + IN ELECTROLYTE)

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Corrosion Cell Dissimilar Metals

i.e. steel pipe connected to copper ground rod

CURRENTFLOW

CURRENT FLOW

IONIZED ELECTROLYTE

WIRE

ANODE(IRON)

CATHODE(COPPER)

CURRENT FLOW

(- TO + IN ELECTROLYTE)

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Corrosion Rate

As a result of this process, electric current flows

through the interconnection between cathode

and anode. The cathodic area is protected from

corrosion damage at the expense of the metal,which is consumed at the anode. The amount

of metal lost is directly proportional to the

current flow. Mild steel is lost at approximately20 pounds for each ampere flowing for a year.

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Factors Affecting Corrosion Rate

Potential Difference Between Anode and

Cathode (Galvanic Series)

Circuit resistance Resistivity of the Electrolyte

Chemical Activity

Stray Currents

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Potential Difference

Interconnecting two dissimilar metals in an

electrolyte will create a corrosion cell. The

strength of this cell increases as the distance

within the galvanic series increases.

G l i S i

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27

Galvanic Series

METAL VOLTS (CSE)

Commercially Pure Magnesium -1.75

Magnesium Alloy -1.60

Zinc -1.10

Aluminum Alloy -1.05 Commercially Pure Aluminum -0.80

Mild Steel (clean & shiny) -0.50 to -0.80

Mild Steel (rusted) -0.20 to -0.50

Cast Iron (not graphitized) -0.50

Lead -0.50 Mild Steel in Concrete -0.20

Copper, Brass, Bronze -0.20

High Silicon Cast Iron -0.20

Carbon, Graphite, Coke +0.30

Example: connecting magnesium to copper will produce a corrosion cell with a

potential of about 1.5 volts.

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Resistance of Common Electrolytes

Soils High resistivity water reduces thecorrosion rate, while low resistivity water

increases the corrosion rate.

CLASSIFICATION

ELECTROLYTERESISTIVITY

(ohm-cm)

ANTICIPATEDCORROSIVITY

Low Resistance 0 to 2,000 Severe

Medium 2,000 to 10,000 Moderate

High 10,000 to 30,000 Mild

Very High Above 30,000 Increasingly Less

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Resistance of Common Electrolytes

Water Approximate resistivity values

Water resistivity Ohms-cm

open sea 20-25

seawater (coastal) 30-40river water 500-10,000

tap water 1,000-10,000

rain water 20,000

distilled water 500,000

pure water 20,000,000

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Chemical Activity

Passive (less corrosive) Environment

High pH (neutral or basic)

Low Moisture Content Lack of Salts

High Resistivity

Low Temperature Homogenous Environment

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Stray current corrosion

Boat1

Boat2

Boat3

Ground

wire

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Corrosion Type

Uniform or near uniform - Corrosion attacks all

areas of the metal at the same or similar rate.

Localized - Some areas of the metal corrode at

different rates due to heterogeneities in the

metal or environment. This type of attack can

approach pitting.

Pitting - Very highly localized attack resulting insmall pits that may penetrate to perforation.

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Commonly Affected Structures

Buried Piping

Steel Piles

Storage Tanks - Above Ground / Underground

Reinforcing Steel in Concrete

Ships/Boats

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Methods to Control Corrosion

Use of Corrosion resistant materials (plastic, stainless

alloys, fiberglass).

Use of the same or similar metals per the galvanic

series. Altering the environment (utilizing homogeneous high

resistivity backfill or inhibitors).

Utilize coatings and linings that electrically insulate thestructure from the electrolyte (paints, plastic films, etc).

Use of Cathodic Protection.

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Fundamentals of Cathodic

Protection

Cathodic Protection (CP) Defined - Minimize

corrosion by utilizing an external source of

electrical current which forces the entire

structure to become a cathode.

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1824: Earliest practical use of cathodic protection

Sir Humphrey Davys work on protecting thecopper sheathing on wooden hulls in the

British Navy by sacrificial zinc or iron anodes is

generally considered to be the earliest

example of practical cathodic protection.

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Galvanic CP

When metals such as magnesium or zinc are

placed in the environment in contact with a

more noble metal such as steel, a current flows

from the more active anode to the noblecathode (corrosion cell).

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Anodes Used for Galvanic CP

Magnesium Magnesium is often used in soil toprotect small electrically isolated structures, suchas underground storage tanks, and well coated

pipelines. Zinc Zinc is often used in marine

environments. They are commonly found onboats.

Aluminum Aluminum can be used for a varietyof marine applications.

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Keys to obtaining enough cathodic protection

Determine amount of current required

Theoretical calculations based on coating quality

and environmentOr, perform current requirement testing

Calculate output expected from anode and

determine number of anodes required.

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Galvanic CP

Pros of Galvanic CP

Inexpensive

Little Maintenance cost No external Power source

A variety of install methods can be used. For

example, many USTs are shipped with anodesattached.

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Galvanic CP

Cons of Galvanic CP

Typically work best with electrically isolated structures.

No external power source, limited driving potential

(driving potential based on the galvanic series) Limited output makes it ineffective when trying to

protect large uncoated surfaces.

Require a low resistivity electrolyte to function well.

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Impressed Current CP

Utilize an external power source to develop a

high potential difference between the surface to

be protected and an anode.

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Impressed Current CP

Anode Groundbed

Rectifier

Negative Cable

Positive Cable

AC Power Supply

Pipeline

IMPRESSED CURRENT SYSTEM

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Impressed Current CP

Pros of Impressed Current CP

Unlimited driving potential.

Capable of protecting large steel structures

when designed properly. Requires less anodes then a galvanic system.

Output can be controlled using a permanent

reference electrode, desirable when theelectrolyte resistivity is known to change.

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Impressed Current CP

Cons of Impressed Current CP

Initial costs can be more expensive.

Requires an external DC power source along

with an AC supply.

System requires routine maintenance and

monitoring.

Anode wires can be susceptible to damage.

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Impressed Current CP Rectifier

A rectifier converts available AC power to low

voltage DC power. Most cathodic protection

rectifiers are provided with a means to vary the

DC output voltage in small increments, or insome cases offer complete control from zero to

100% of rated DC output.

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CP System Testing

A CP system can be evaluated by obtaining a

reference cell potential. This potential

determines the amount of cathodic polarization

the structure is receiving.Adequate protection is indicated by obtaining a

value more negative then the established criteria.

This criteria is specific to the reference cell usedto obtain potentials.