Cathodic Protection for Pipelines & Casings. Corrosion Process.

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Cathodic Protectionfor Pipelines & Casings

Corrosion Process

Corrosion Can be Defind as Either:

•Practical:Tendency of a Metal to Revert into it‘s Native State

• Scientific: Electrochemical Degradation of Metal as a Result of a Chemical Reaction with its Environment

Cathodic Protection

Cathodic protection (CP) is a technique to control the corrosion of a metal surface by making it work as a cathode of an electrochemical cell.

Cathodic protection systems are most commonly used to protect Steel, water or fuel Pipelines and Storage tanks, steel pier Piles, Ships, Offshore Oil Platforms and onshore Oil & Gas Well casings.

Major Components of a Cathodic Protection system

Transformer Rectifier

Impressed Current Anodes

Permanent Test Stations

Enclosures/Cabinets/Boxes

Alternative DC Power Surces

Sacrificial Anodes

Permanent Reference Electrodes

Cables

Cable Connection Accessories Measuring Equipments

Electrical Isolation From Other Structures is Necessary

Pipeline CP Systems: 1. Cathodic Protection for Simple pipeline

2. Cathodic Protection for pipeline with more components

2. Cathodic Protection for pipeline with more components

2. Cathodic Protection for pipeline with more components

3. Temporary CP system for pipeline by using Sacrificial anodes

Casing CP System

Casing CP System

Cathodic Protection Procedure

MEASUREMENTS

Survey of CP Stations

Soil Resistivity Measurements

Current Density Measurements

Calculation of Protective Range

Survey of Electrical Power Supply for CP Station

Cathodic Protection ProcedureENGINEERING

Site Survey Report

Description & Standards

Detail Design

Design Criteria & Calculations

Material Specification

Installation Instructions

Start up & Commissioning

Documentation

Maintenance Instructions