Corrosion Failures

K. Elayaperumal has close to 50 years of experience in Corrosion and Metallurgical Analysis. Since 1979 he has been a Corrosion & Metallurgical Consultant extending advisory Consultancy Services in the areas of Corrosion Prevention, Materials Selection, Failure Analysis, Water treatment etc. as related to Process Industry. He is the recipient of the National Metallurgist Award instituted by Ministry of Iron and Steel, Government of India, for contribution in Corrosion Prevention and Failure Analysis and also the Life Time Achievement Award from NACE International India Chapter.V. S. Raja is currently a professor in the Department of Metallurgical Engineering and Materials Science at the Indian Institute of Technology Bombay, Mumbai, India. He has guided about 20 doctoral and 100 master’s students in Corrosion and has been a Consultant to over 50 industries; has over 120 publications in various peer reviewed journals & books and also delivered over 100 plenary, keynote and invited talks in conferences. He is a recipient of Meritorious award by NACE international India Section and Excellence in Teaching award by IIT Bombay and a Fellow of NACE International and Indian Institute of Metals.

• About the Authors xiiiForeword xvPreface xvii1 Introduction 11.1 The Phenomenon of Corrosion 11.2 Importance of Corrosion 21.2.1 Cost of Corrosion: Direct and Indirect 21.3 The Purpose and Format of the Book 6References 72 Thermodynamics and Kinetics of Electrochemical Corrosion 92.1 Introduction 92.2 Thermodynamics 102.2.1 Corrosion Reactions and Gibbs Free Energy Change 102.2.2 Electrochemical Nature of Corrosion 112.2.3 Summary 162.3 Kinetics of Corrosion 172.3.1 Description of a Corrosion System 182.3.2 Predicting Corrosion 192.3.3 Passivity 212.3.4 Summary 222.4 Corrosion Evaluation and Monitoring 232.4.1 Electrochemical Techniques 242.4.2 Non-electrochemical Techniques 26References 273 Forms of Corrosion 293.1 Introduction 293.2 Uniform Corrosion 303.3 Galvanic Corrosion 313.3.1 Factors Affecting Galvanic Corrosion 313.3.2 Controlling Galvanic Corrosion 343.4 Pitting Corrosion 353.4.1 Pitting Process and Pitting Morphology 353.4.2 Factors Affecting Pitting Corrosion 353.4.3 Controlling Pitting Corrosion 383.5 Differential Aeration-Assisted Corrosion (Crevice Under Deposit and Water-Line Corrosion) 393.5.1 Characteristics of Differential Aeration Corrosion 393.5.2 Factors Affecting Differential Aeration Corrosion 403.5.3 Differential Aeration Corrosion Control 413.6 Intergranular Corrosion 413.6.1 IGC of Stainless Steels 413.6.2 Weld Decay of Stainless Steels 453.7 Selective Dissolution/Selective Attack 473.7.1 Characteristics of Selective Dissolution 473.7.2 Dezincification 473.7.3 Graphitic Corrosion 493.8 Flow-Assisted/Erosion/Cavitation Corrosion 503.8.1 Flow-Assisted Corrosion (FAC) 503.8.2 Erosion Corrosion 513.8.3 Cavitation Damage 553.9 Stress Corrosion Cracking 553.9.1 Characteristics of SCC 563.9.2 Effect of SCC on Mechanical Properties 573.9.3 Factors Affecting SCC 593.9.4 Controlling SCC 633.10 Hydrogen Damage 633.10.1 Low Temperature Hydrogen-Induced Cracking 633.10.2 High Temperature Hydrogen Damage/Decarburization 673.11 Stray Current Corrosion 683.12 High Temperature Corrosion 703.12.1 Oxidation 703.12.2 Sulfidation 713.12.3 Hot Corrosion 713.12.4 Chloridation 713.12.5 Carburization/Metal Dusting 72References 724 Materials of Construction for Chemical Process Industries 754.1 Introduction 754.2 Cast Irons 764.3 Carbon Steels 784.3.1 Corrosion 794.3.2 Stress Corrosion Cracking Including Hydrogen Cracking and Sulfide Stress Cracking 804.3.3 Caustic Stress Corrosion Cracking 814.3.4 Favorable and Unfavorable Points in Using Carbon Steel as MOC 824.4 Low Alloy Steels 824.5 Stainless Steels 864.5.1 Ferritic/Martensitic Stainless Steels 874.5.2 Austenitic Stainless Steels 884.5.3 Super Austenitic Stainless Steels 924.5.4 Duplex Stainless Steels 944.6 Nickel Base Alloys 964.7 Copper Base Alloys 964.8 Titanium 994.9 Aluminum Alloys 1004.10 Nonmetallic Materials 1024.11 Ceramics/Inorganic Oxide Glasses 1034.12 Organic Polymers/Plastics 1034.13 Materials Selection for Corrosion Prevention in Hydrocarbon Service 1044.13.1 Materials Selection as per NACE MR0175 107References 1095 Failure Analysis Procedure with Reference to Corrosion Failures 1115.1 Introduction 1115.2 Purpose of Failure Analysis Investigations 1125.3 Failure Analysis Steps 1125.3.1 Site Visit 1125.3.2 Tests on the Samples 1145.3.3 Analysis Interpretation and Diagnosis of the Failure 1165.4 Failure Analysis Report: Contents and Preparation 117References 1186 Case Studies 1196.1 Preamble 119Classification of Case Studies 120General 1231 Bromine Preheater in a Pharmaceutical Fine Chemical Plant 1242 Structurals in a White Clay Manufacturing Plant 1253 Sea Water Cooler Tubes in an Oil Refinery 1264 Package Boiler Tube in an Organic Chemical Plant 1275 Shell of a Packed Column for Ammonia and Water Contact in an Ammonia Processing Plant 1286 Instrumentation Tube in an Offshore Platform of an Oil and Gas Plant 1297 Plate Type Heat Exchanger/Cooler in a Sulfuric Acid Plant 1308 Dissimilar Stainless Steel Weld in an Organic Chemical Plant 1319 Digestor Preheater in a Pulp and Paper Plant 13210 Esterification Column in an Organic Chemical Plant 13311 Half Pipe Limpet Coil of a Stirred Reactor in an Organic Chemical Plant 13412 Firewater Lines Buried Underground in an Organic Chemical Plant 13513 Alcohol Superheater in a PVC Manufacturing Petrochemical Plant 13614 Package Boiler Tubes in an Alcohol Distillery Plant 13715 Reducers in a Reformer Tube in an Ammonia Plant of a Fertilizer Industry 13816 Pressure Safety Valve (PSV) Fitting on Instrumentation Tubes in an Off-shore Platform in an Oil and Gas Company 13917 Water Drum (Mud Drum) Shell in a Coal-Fired Steam Boiler 14018 Tubes in a Kettle Re-boiler of an Amine Plant 14119 Evaporator Tubes in an Organic Chemical Plant 14220 Top Tube Sheet Vent Equalizer Weld Zone of a Gas Cooler in a Petrochemical Plant 14321 Bottom Row Tubes in a Kettle Re-boiler of an Organic Chemical Plant 14422 Cages for Filter Bags in an Inorganic Chemical Plant 14523 High Temperature Generator (HTG) Tubes of Vapor Absorption Chiller of an Air-Conditioning and Refrigeration Unit 14624 Gasket Seat in a Shell and Tube Condenser in a Petrochemical Plant 14725 Acid Gas CO2 Cooler Condenser in Ammonia Plant of a Fertilizer Unit 14826 Naphtha Coolers in a Fertilizer Plant 14927 U Type Jet Dyeing Machine in a Textile Dyeing Unit 15028 Acetic Acid Manufacturing Unit in a Petrochemical Plant 15129 Large Stainless Steel Pipeline in a Urea Plant of a Fertilizer Unit 15230 Heat Recovery System of a PVC Unit in a Petrochemical Plant 15331 EDC Furnace Coil of a PVC Plant in a Petrochemical Unit 15532 Internals of a Stirred Reactor Processing Ortho Phosphoric Acid 15733 Salt Evaporator 15834 Cooler/Condenser Tubes of an Absorption Chiller Machine of an Airconditioning Plant 15935 Nitro Mass Cooler in an Organic Chemical Plant 16136 Fertilizer Industry Ammonia Plant Natural Gas Feed Preheater Coil 16237 Petrochemical Unit. PVC Plant. Radiant Coils of the EDC Pyrolysis Furnace 16438 Exhaust Gas Boiler in a Sugar Mill 16639 Domestic Storage Water Heater 16740 Stirred Reactor in a Rubber Chemical Plant 16841 Stainless Steel Tubes During Long Storage in Packed Condition 16942 Fertilizer Plant. Ammonia Units. Secondary Waste Heat Boiler Tubes 17043 Hospital Hydroclave for Treating Wastes 17244 Petrochemical Plant. Phosgene Absorption Column Internals 17445 Fertilizer Unit Ammonia Plant Start-Up Preheater Outlet Line 17646 Petrochemical Plant Underground Fire–Water Pipelines 17747 Monel Clad Evaporator in a Pure Water Plant 17848 Loop Steamer Machine in a Textile Dyeing Unit 17949 Rubber Chemicals Plant: Leakage in Process Pipelines 18050 Clay Drier in a Clay manufacturing Plant 18151 Hydrogen Sulfide Processing Plant 18252 Textile Bleaching Vessel in a Dyeing Industry 18453 Condenser of an Absorption Chilling Machine in an Air-Conditioning Plant 18554 Petrochemical Complex: Lube Oil Cooler Tubes of Captive Gas Turbine Power Plant 18755 Petrochemical Plant: Plate Heat Exchanger (PHE) Exchanging Heat Between Spent Caustic and Vent Gas in a Cracker Plant 18856 Inorganic Chemical Plant: Distillation Pots 18957 Starch Industry: Economizer Tubes of High Pressure Captive Boilers 19058 Rubber Chemical Plant–Crump Slurry Tank 19159 Petrochemical Plant: Gas Cracker Unit Dilute Steam Kettle Re-boiler 19360 Textile Dyeing Unit: Jet Dyeing Machine Shell 19461 Oil Refinery: 12 Inch Dia. Overhead Pipeline 19562 Fertilizer Plant: CO2 Compressor Inter-stage Cooler 19663 Oil Refinery: Flash Crude Heater Shell Cover Drain Nozzle 19864 Oil Refinery: Light Cycle Oil Steam Generator 19965 Organic Chemical Plant: High Pressure Autoclave in R&D Laboratory 20066 Fertilizer Industry: Captive Power Plant: Economizer Tube 20267 Inorganic Chemicals Plant: Reactor Shell 20368 Reactor for an Organic Chemical Plant 20469 Fertilizer Unit. Ammonia Plant. Primary Waste Heat Boiler 20570 Pulp and Paper Plant. TL Vertical Screen Inlet Line of the Paper Section 20771 Fertilizer Plant. Underground Sections of Cooling Water and Fire Hydrant Water Pipe Lines 20872 Thermal Power Plant. Condenser Cooling Sea Water In-take Line. Butter Fly Valve 21073 Petrochemical Plant. Pressure Transmitter Sensors 21174 Organic Chemicals Plant: Coolers and Condensors 21275 Organic Chemicals Plant: Alcohol Vaporizer 21476 Organic Chemicals Plant. Thermowells 21577 Fertilizer Unit. Ammonia Plant. Gas to Gas Heat Exchanger 21678 Oil Refinery. Sulfolane Recovery Column Reboiler 21779 Oil Refinery. Hydrocarbon vapor-liquid heat exchanger 21880 Chlor-Alkali Plant Stainless Steel Laboratory Reactor 219Index 221