Corrosion and Materials Selection

Alireza BahadoriSchool of Environment, Science and Engineering, Southern Cross University, Australia.

• About the Author xxi Preface xxiiiAcknowledgements xxv1. Fundamentals of Corrosion in the Oil, Gas, and Chemical Industries 11.1 Uniform Corrosion 21.2 Localized Corrosion 31.2.1 Galvanic Corrosion 31.2.2 Pitting Corrosion 31.2.3 Selective Attack 31.2.4 Stray Current Corrosion 41.2.5 Microbial Corrosion 41.2.6 Intergranular Corrosion 41.2.7 Concentration Cell Corrosion (Crevice) 41.2.8 Thermogalvanic Corrosion 41.2.9 Corrosion Caused By Combined Action 51.2.10 Corrosion Fatigue 51.2.11 Fretting Corrosion 51.2.12 Stress Corrosion Cracking 51.2.13 Hydrogen Damage 51.3 Low-Temperature Corrosion 61.3.1 Low-Temperature Corrosion by Feed-Stock Contaminants 61.3.2 Low-Temperature Corrosion by Process Chemicals 81.4 High-Temperature Corrosion 121.4.1 Sulfidic Corrosion 131.4.2 Sulfidic Corrosion without Hydrogen Present 131.4.3 Sulfidic Corrosion with Hydrogen Present 131.4.4 Naphthenic Acids 141.4.5 Fuel Ash 161.4.6 Oxidation 162. Corrosion Problems in the Petroleum and Chemical Industries 172.1 Stress Corrosion Cracking and Embrittlement 172.1.1 Chloride Cracking 182.1.2 Caustic Cracking 212.1.3 Ammonia Cracking 232.1.4 Amine Cracking 252.1.5 Polythionic Acid Cracking 252.1.6 Hydrogen Damage 262.2 Hydrogen Attack 302.2.1 Forms of Hydrogen Attack 312.2.2 Prevention of Hydrogen Attack 322.3 Corrosion Fatigue 332.3.1 Prevention of Corrosion Fatigue 332.4 Liquid-Metal Embrittlement 332.4.1 Prevention of Zinc Embrittlement 342.5 Basic Definition of Erosion-Corrosion 352.5.1 Cavitation 352.6 Mixed-Phase Flow 352.7 Entrained Catalyst Particles 362.8 Systematic Analysis of Project 362.8.1 Organization of Work 382.8.2 Teamwork 382.8.3 Sources of Information 402.8.4 Environmental Conditions 412.8.5 Case Histories and Technical Data Records 422.8.6 Analysis 432.9 Forms of Corrosion and Preventive Measures 432.9.1 Uniform or General Corrosion 442.9.2 Galvanic or Two-Metal Corrosion 452.9.3 Crevice Corrosion 462.9.4 Pitting 472.10 Selective Leaching or De-Alloying Corrosion 492.10.1 Dezincification: Characteristics 492.10.2 Graphitization 492.11 Erosion-Corrosion 502.11.1 Surface Films 512.11.2 Effect of Velocity 512.11.3 Effect of Turbulent Flow 512.11.4 Effect of Impingement 522.11.5 Galvanic Effect 522.11.6 Nature of Metal or Alloy 522.11.7 Combating Erosion-Corrosion 522.12 Stress Corrosion Cracking 522.12.1 Crack Morphology 532.12.2 Stress Effects 532.12.3 Corrosion Fatigue 532.12.4 Methods of Prevention 532.13 Types of Hydrogen Damage 542.13.1 Causes of Hydrogen Damage 542.13.2 Preventive Measures 552.14 Concentration Cell Corrosion 552.14.1 Metal Ion Concentration Cells 552.14.2 Oxygen Concentration Cells 552.14.3 Active–Passive Cells 552.15 Filiform Corrosion 562.16 Types of Intergranular Corrosion 562.17 Microbiologically Influenced Corrosion 572.18 Corrosion in Concrete 583. Corrosion Considerations in Material Selection 613.1 Corrosion in Oil and Gas Products 613.1.1 Effect of CO2 623.1.2 Effect of Temperature 623.1.3 Effect of Pressure 623.1.4 Prediction of CO2 Corrosion Rate 623.1.5 Effect of H2S 683.2 Corrosives and Corrosion Problems in Refineries and Petrochemical Plants 743.2.1 Sulfur Content 743.2.2 Erosion 753.2.3 Naphthenic Acid 753.2.4 Hydrogen 753.2.5 Polythionic Stress Cracking 753.2.6 Caustic Embrittlement by Amine Solution 753.2.7 Salts 753.2.8 Condensate 753.2.9 High Temperature 753.2.10 CO2 Corrosion 763.2.11 Amine Solution 763.2.12 H2S 763.2.13 H2SO4 763.2.14 Hydrogen Fluoride 763.2.15 Acetic Acid 763.2.16 Ammonia 773.2.17 Fuel Ash 773.2.18 Micro-organisms 773.2.19 Special Material Requirements for Refinery Equipment 773.2.20 Special Equipment Requirements for Pressure Vessels (Including Exchanger Shells, Channels, etc.) 783.2.21 Storage Tanks 793.2.22 Heat Exchanger Tube Bundles 793.2.23 Furnaces 803.2.24 Piping 803.2.25 Low-Temperature Piping 803.2.26 Corrosion-Resistant Piping 813.2.27 Corrosion-Resistant Valves 813.2.28 Flare Systems 823.2.29 Rotating Machinery 823.2.30 Special Material Requirements in Petrochemical Plants 823.2.31 Supplemental Requirements for Equipment in Sour Service 823.2.32 Carbon Steel 863.2.33 Fabrication Requirements 884. Engineering Materials 894.1 The Range of Materials 894.2 Properties of Engineering Materials 894.3 Corrosion Prevention Measures 914.3.1 Cathodic Protection 914.3.2 Coating, Painting, and Lining Materials 924.3.3 Inhibitors 924.4 Material Selection Procedure 934.5 Guidelines on Material Selection 934.6 Procedure for Material Selection 964.7 Process Parameters 974.8 Corrosion Rate and Corrosion Allowances 974.8.1 Calculation 984.8.2 Corrosion Study by Literature Survey 984.8.3 Corrosion Tests 984.9 Corrosion Allowance 1004.10 Selection of Corrosion-Resistance Alloys 1004.11 Economics in Material Selection 1024.11.1 Cost-Effective Selection 1024.11.2 Economic Evaluation Techniques 1024.12 Materials Appreciation and Optimization 1034.13 Corrosion in Oil and Gas Products 1044.14 Engineering Materials 1054.14.1 Ferrous Alloys 1054.14.2 Carbon Steels 1054.14.3 Surface Hardening 1064.14.4 Alloy Steels 1064.15 Cast Iron 1124.15.1 Malleable Irons 1124.15.2 Alloy Cast Irons 1124.16 Non-Ferrous Metals 1134.16.1 Aluminum 1134.16.2 Copper 1134.16.3 Lead and its Alloys 1164.16.4 Nickel 1164.16.5 Titanium 1164.17 Polymers 1164.17.1 Thermoplastics 1164.17.2 Elastomers 1204.17.3 Thermosetting Materials 1204.18 Ceramics and Glasses 1204.19 Composite Materials 1234.19.1 Timber and Plywood 1234.19.2 Fiber-Reinforced Materials 1234.19.3 Sandwich Structures 1235. Chemical Control of Corrosive Environments 1255.1 General Requirements and Rules for Corrosion Control 1255.1.1 Corrosion Inhibitors 1265.1.2 Types of Inhibitor 1265.2 Basic Types of Inhibitors and How They Work 1275.2.1 Polarization Diagrams 1275.2.2 Types of Inhibitor 1285.3 Corrosive Environments 1375.3.1 Aqueous Systems 1375.3.2 Strong Acids 1385.3.3 Non-Aqueous Systems 1385.3.4 Gaseous Environments 1385.3.5 Effect of Elevated Temperatures 1385.4 Techniques for the Application of Inhibitors 1395.4.1 Continuous Injection 1395.4.2 Batch Treatment 1395.4.3 Squeeze Treatment 1395.4.4 Volatilization 1395.4.5 Coatings 1405.5 Inhibitor Mechanisms 1405.5.1 Neutralizing Inhibitors 1405.5.2 Filming Inhibitors 1405.5.3 Scavengers 1405.5.4 Miscellaneous Inhibitors 1415.6 Criteria for Corrosion Control by Inhibitors 1415.7 System Condition 1415.8 Selection of Inhibitors 1435.8.1 Procedure for Selection 1435.9 Economics of Inhibition 1505.10 Environmental Factors for Corrosion Inhibitor Applications 1515.10.1 Aqueous Systems 1515.10.2 Effects of Various Dissolved Species 1515.10.3 Gaseous Environments 1556. Requirements for Corrosion Control in the Petroleum and Petrochemical Industries 1596.1 Exploration 1596.1.1 Factors Important in Corrosion Attack During Drilling and Their Control 1606.1.2 Some Problems Related to Water-Based Fluids and Their Control 1616.1.3 Techniques to Control Corrosion in Drilling Operations 1636.2 Production 1676.2.1 Characteristics of Oil and Gas Wells 1676.2.2 Oil Wells 1676.2.3 Gas Wells 1686.2.4 Offshore Production 1696.3 System Requirements for Corrosion Control of Oil Fields by Inhibitors 1696.3.1 Pipelines and Flow Lines 1696.3.2 Production Systems 1696.3.3 Other Factors Affecting Corrosion Inhibitor Requirements 1716.4 Types of Inhibitor 1726.5 Selection of Inhibitor 1736.6 Measurement 1746.7 Factors Governing Oil Well Corrosion 1756.8 Application of Inhibitor 1776.8.1 Gas Condensate and Flowing Oil Wells 1776.8.2 Gas Lift Wells 1796.8.3 Pumping Wells 1796.8.4 Gas Pipelines 1806.9 Water Flooding and Water Disposal 1816.10 Transportation and Storage 1816.10.1 Corrosion Control by Inhibitor 1816.11 Biological Control in Oil and Gas Systems 1836.11.1 Culture and Identification 1836.11.2 Scales and Deposits 1846.11.3 Chemical Control 1846.12 Scale Control in Oil Systems 1856.12.1 The Formation of Scale 1856.12.2 Oilfield Scales 1866.12.3 Preventing Scale Formation 1886.12.4 Relative Effectiveness of Scale Control Chemicals 1906.12.5 Types of Scale Inhibitor 1916.12.6 Identification of Scale 1916.12.7 Predicting Scale Formation by Calculation 1927. Corrosion Inhibitors in Refineries and Petrochemical Plants 2057.1 Nature of Corrosive Fluids 2057.1.1 Gas Phase 2067.1.2 Liquid Hydrocarbon Phase 2067.1.3 Liquid Aqueous Phase 2067.2 Corrosion of Steel 2067.3 Corrosion of Copper Alloys 2077.4 Neutralizing Corrosion Inhibitors 2077.5 Filming Inhibitors 2087.6 Special Concepts in the Use of Corrosion Inhibitors in Refineries 2097.6.1 Temperature Limitations 2097.6.2 Insufficient Concentration 2097.6.3 Surfactant Properties of Inhibitors 2097.7 Economic Aspects of Chemical Inhibition and Other Measures for Corrosion Prevention 2107.7.1 Altering the Metal 2107.7.2 Corrosion Prevention Barriers 2107.7.3 Altering the Corrosive Environment 2117.8 Special Refinery Processes Amenable to Corrosion Inhibitors 2117.8.1 Hydrogen Blistering Problems 2117.9 Corrosion in Gas Processing Units 2127.10 Miscellaneous Refinery Corrosion Problems 2137.11 Selection of Inhibitor 2147.11.1 Test Methods 2147.12 Control of Fouling 2147.12.1 Inorganic Fouling Deposits 2157.12.2 Organic Fouling Deposits 2157.12.3 Use of Anti-Foulants 2167.12.4 Evaluation of Anti-Foulants 2167.13 Utility (Cooling Water and Boiler Systems) 2187.13.1 Corrosion Control in Cooling Water Systems 2187.13.2 Corrosion Control in Boiler Systems 2207.14 Boiler Corrosion Problems 2217.14.1 Deposits in Boilers 2217.14.2 Problems from Carryover 2217.14.3 Corrosion Problems 2237.14.4 High-temperature hot water systems 2347.15 Treatment of Acid Systems 2357.15.1 Industrial Exposures of Metals to Acids 2357.15.2 Cleaning of Oil Refinery Equipment 2357.15.3 Heat Exchangers 2367.15.4 Oil-Well Acidizing 2367.15.5 Manufacturing Processes 2367.15.6 Vapor–Liquid Systems: Condensing Vapors 2377.16 Chemical Cleaning of Process Equipment 2377.16.1 Fouling of Equipment 2377.17 Critical Equipment Areas 2397.17.1 Columns 2397.17.2 Glass-Lined Vessels 2397.17.3 Oxygen, Chlorine, and Fluorine Piping Systems 2397.18 Identification of Deposits 2397.18.1 Preoperational Cleaning 2417.18.2 Boilers 2417.18.3 Columns 2417.18.4 Shell and Tube Heat Exchangers 2417.18.5 Cleaning of Boilers 2417.18.6 Cleaning of Furnaces 2427.18.7 Cleaning of Pumps and Compressors 2427.18.8 Cleaning of Piping 2427.19 Chemical Cleaning 2427.19.1 Chemical Cleaning Methods 2437.19.2 Chemical Cleaning Solutions 2448. Corrosion Inhibitor Evaluations 2478.1 On-Line Monitoring of Corrosion 2478.2 Corrosion Monitoring Techniques 2488.3 Selecting a Technique for Corrosion Monitoring 2488.3.1 Where the Primary Objective is Diagnosis in a New Situation 2488.3.2 Where the Primary Objective is to Monitor the Behavior of a Known System 2518.3.3 Criteria for Selection of Technique 2518.4 Corrosion Monitoring Strategy 2548.4.1 Equipment 2558.4.2 Weight Loss Coupons 2558.4.3 Spool Pieces 2568.4.4 Field Signature Method (Electric Fingerprint) 2568.4.5 Electrical Resistance Probes 2578.4.6 Electrochemical Probes 2588.4.7 Electrochemical Noise 2588.4.8 Solid Particle Impingement Probes 2598.4.9 Hydrogen Probes and Patch Monitors 2598.4.10 Galvanic Probes 2608.4.11 Electrical Potential Monitoring 2608.4.12 pH Probes 2618.4.13 Measurement of Dissolved Gases 2628.4.14 Pipeline Inspection Tools 2638.4.15 Ultrasonic Thickness Measurement 2648.4.16 Radiography 2648.4.17 Side Stream Monitoring 2658.4.18 Visual Inspection 2658.4.19 Failure Analysis 2658.4.20 Bacterial Methods 2658.5 Measurement of Dissolved Solids 2678.6 Measurement of Suspended Solids 2678.7 Corrosion Product Analysis 2678.8 Design Requirements 2688.8.1 Access Fitting Location 2688.8.2 Access Fitting Design 2688.8.3 Materials Selection 2698.9 Automated Systems 2708.9.1 Manual Methods 2708.9.2 Data Loggers/Collection Units 2708.9.3 Transmitter Units 2708.9.4 Computers 2708.9.5 Data Analysis and Reporting 2718.9.6 Guidelines for Safe On-Line Installation and Retrieval of Corrosion Monitoring Devices 2718.10 Evaluation of Corrosion Inhibitors 2738.10.1 Reasons for Inhibitor Testing 2738.10.2 Inhibitor Properties 2748.10.3 Test Conditions 2748.11 Detection of Corrosion 2758.11.1 Methods Involving Loss of metal 2758.11.2 Indirect Measurements for Corrosion Detection 2768.11.3 Utilization of Film Measurements 2778.12 Miscellaneous Corrosion Tests 2788.13 Results of the Test Method 2788.14 Field Testing of Inhibitors 2798.14.1 Illustrations of Complex Testing Procedures Necessary to Simulate Field Conditions 2798.15 Inhibitor Properties Other Than Effectiveness in Mitigating Corrosion 2838.15.1 Influence of Density 2848.15.2 Influence of Solubility 2848.15.3 Surface-Active Characteristics 2858.15.4 Testing for Solubility, Dispersibility, Emulsion, and Foaming 2858.15.5 Formation of Sludges or Precipitates 2858.15.6 Ecological Effects 2868.15.7 Effects of Temperature 2868.16 Monitoring of Corrosion Inhibitors 2868.16.1 Water Samples 2868.16.2 Corrosion Coupons 2878.16.3 Inhibitor Residuals 2878.16.4 Electric Resistance Probes and Corrosion Monitoring Probes 2878.17 Corrosion Behavior of High-Alloy Tubular Materials in Inhibited Acidizing Conditions 2888.17.1 Experimental Procedure 2888.17.2 Weight Loss 2928.17.3 Low-Alloy Steel 2928.17.4 Crevice Corrosion 2928.17.5 Conclusions and Recommendations 2929. Compatibility in Material Selection 2959.1 Requirements for Compatibility 2969.2 Structures and Equipment 3009.3 Piping Systems 3029.4 Fasteners 3049.5 Encapsulation, Sealing, and Enveloping 3069.6 Electrical and Electronic Equipment 3069.6.1 Grounding and Bonding of Electrical Equipment 3079.7 Coatings, Films, and Treatments 3089.8 Chemical Compatibility 3109.9 Environment 3119.10 Stray Currents 3119.11 Beneficial Results 3139.12 Shape or Geometry 3139.12.1 Requirements 3149.13 Structures 3159.13.1 Piping Systems 3179.13.2 Tanks and Vessels 3219.14 Mechanics 3229.14.1 Requirements 3239.14.2 Structures 3279.14.3 Equipment 3299.14.4 Piping Systems 3319.14.5 Vibration Transfer 3329.14.6 Surface Treatment (from a Mechanical Point of View) 3339.14.7 Electrical and Electronic Equipment (from a Mechanical Point of View) 33410. Surface Preparation, Protection and Maintenance 33710.1 Surface 33710.1.1 Requirements 33710.1.2 Structures 34210.1.3 Equipment 34510.1.4 Piping Systems (from a Surface Point of View) 34610.1.5 Surface Preparation 34710.1.6 Electrical and Electronic Equipment 35010.2 Protection 35010.2.1 Requirements 35210.2.2 Protection by Separation of Materials from the Environment 35210.2.3 Electrochemical Cathodic and Anodic Protection 36010.2.4 Protection by Adjustment of Environment 36210.2.5 Protection of Structures 36310.2.6 Protection of Equipment 36710.2.7 Protection of Pipe Systems 36810.2.8 Protection of Electrical and Electronic Equipment 37010.3 Maintenance 37310.3.1 Requirements 37410.3.2 Structures and Equipment 37510.4 Economics 37610.4.1 Requirements 37710.4.2 Methods of Appraisal 38010.4.3 Economics Applied to Structures 38110.4.4 Economics Applied to Equipment and Pipe Systems 38211. Fabrication and Choice of Material to Minimize Corrosion Damage 38511.1 Design 38511.2 Materials 38711.2.1 Specific Material Considerations: Metals 38811.2.2 Material Considerations: Non-metals 38911.3 Fabrication 38911.3.1 Welding 39011.4 Welding Procedure 40811.4.1 Welding of Stainless Steels 40811.4.2 Cleaning Procedures 40911.4.3 Weld Design and Procedure 40911.4.4 Weld Defects 40911.4.5 Carbon and Low-Alloy Steels 40911.4.6 Stainless steels 41111.4.7 Nickel Alloys 41211.4.8 Aluminum Alloys 41211.4.9 Other Materials for Welding 41311.5 Welding and Joining 41311.5.1 Mechanical Fasteners 41411.5.2 Joining, Brazing, and Soldering 41411.5.3 Protection of welded joints 41411.5.4 Pressure Pipe Brazing and Soldering 41511.6 Soldered Joints 41611.7 Brazed Joints 41711.8 Pipe Bending and Forming 41811.8.1 Bending 41811.8.2 Forming 42112. Heat Treatment 42312.1 General Heat Treatment Requirements 42312.1.1 Governing Thickness 42412.1.2 Heating and Cooling 42412.1.3 Temperature Verification 42512.1.4 Hardness Tests 42512.1.5 Specific Requirements of Heat Treatment 42512.1.6 Alternative Heat Treatment 42612.1.7 Exceptions to Basic Requirements 42612.1.8 Dissimilar Materials 42612.1.9 Delayed Heat Treatment 42612.1.10 Partial Heat Treatment 42612.1.11 Local Heat Treatment 42612.1.12 Heat Treatment of Casing and Tubing 42712.2 Heat Treatment Process 42712.2.1 Heat Treatment of Stainless Steel 42812.3 Preheating of Metals 42912.3.1 Requirements and Recommendations 43012.3.2 Heat Treatment Specific Requirements 43012.4 Surface Treatment of Stainless Steel 43212.4.1 Surface Condition 43212.4.2 Passivation Techniques 43212.4.3 Cleaning 43212.4.4 Passivating 43312.4.5 Testing 43312.5 Handling, Transport, Storage, and Erection of Coated Metalwork 43412.5.1 Selection of Coating Systems 43412.5.2 Methods of Preventing Damage 43412.5.3 Storage of Coated Steelwork 43412.5.4 Responsibilities for Preventing Damage 43512.5.5 Transportation, Handling, and Storage of Coated Pipes 43512.5.6 Handling and Storage of Aluminium 43612.6 Inspection 43712.6.1 Importance of Inspection 43712.6.2 Results of a Lack of Good Inspection 43712.7 Corrosion of Carbon Steel Weldments 43812.7.1 SCC in Oil Refineries 43812.7.2 Leaking Carbon Steel Weldments in a Sulfur Recovery Unit 43812.7.3 Corrosion of Welds in Carbon Steel Deaerator Tanks 44012.7.4 Weld Cracking in Oil-Refinery Deaerator Vessels 440Discussion 442Conclusions 44312.8 Corrosion of Austenitic Stainless Steel Weldments 44412.8.1 Effects of GTA Weld Shielding Gas Composition 44412.8.2 Effects of Heat-Tint Oxides on the Corrosion Resistance Of Austenitic Stainless Steels 44412.8.3 Unmixed Zones 44612.8.4 Chloride SCC 44612.8.5 Caustic Embrittlement (Caustic SCC) 44712.8.6 Microbiologically Induced Corrosion (MIC) 44812.9 Corrosion of Ferritic Stainless Steel Weldments 44812.9.1 Leaking Welds in a Ferritic Stainless Steel Wastewater Vaporizer 44812.10 Corrosion of Duplex Stainless Steel Weldments 45112.10.1 Intergranular Corrosion 45112.10.2 Pitting Tests 45112.11 Stress-Corrosion Cracking 45612.12 Use of High-Alloy Filler Metals 45612.13 Corrosion of Nickel-Bases Alloys 45612.13.1 The Nickel–Molybdenum Alloys 45612.13.2 The Nickel–Chromium–Molybdenum Alloys 457Glossary of Terms 461Bibliography 523Index 535