Steelwork corrosion Control Second edition D.A. Bayliss and d. H. Deacon C D.A. Bavliss and D. H. Deacon
Steelwork Corrosion Control Second edition D. A. Bayliss and D. H. Deacon © 2002 D. A. Bayliss and D. H. Deacon
First published 2002 by Spon Press II New Fetter Lane London ec4p 4eE Simultaneously published in the USA and Canada by Spon Press 29 West 35th Street. New York. NY 1000 1 This edition published in the Tayl Spon Press is an imprint of the Taylor Francis Group e 2002 D. A Bayliss and D. H. Deacon All rights reserve part of this book may be reprinted or reproduce mechanical, or other means, now known or hereafter invented including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library rary of Congress Cataloging in Publication Data A catalog record for this book has been requested ISBN 0-203-30114-.5 Master e-book ISBN ISBN 0-203-34048-5(Adobe eReader Format) ISBN 0-415-26101-5 (Print Edition) C 2002 D. 4. Bavliss and D. H. Deacon
First published 2002 by Spon Press 11 New Fetter Lane, London EC4P 4EE Simultaneously published in the USA and Canada by Spon Press 29 West 35th Street, New York, NY 10001 Spon Press is an imprint of the Taylor & Francis Group © 2002 D. A. Bayliss and D. H. Deacon All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data A catalog record for this book has been requested ISBN 0-415-26101-5 This edition published in the Taylor & Francis e-Library, 2004. ISBN 0-203-30114-5 Master e-book ISBN ISBN 0-203-34048-5 (Adobe eReader Format) (Print Edition) © 2002 D. A. Bayliss and D. H. Deacon
Contents 1 Introduction 1.1 Health and safety considerations 2 The corrosion of steel 2. 1 Corrosion: the basic process 2.2 The electrochemical nature of corrosion 2.3 Corrosion terminology 2.3.1 Potential 2.3.2 Polarisation 2.4 Corrosion in air 2.4.1 Steel composition 2. 4. 2 Rust 2.5 Corrosion in water 2.5.1 Composition of water 2.5.2 Operating conditions 2.5.3 Steel composition 2.5.4 Corrosion rates of steel in water 2.6 Corrosion in soil 2. 7 Bacterial corrosion 2.8 Health and safety considerations ences Further reading 3 Surface preparation 3.1 Steel surface contaminants and condition 3.1.1 Oil and grease C D.A. Bavliss and D. H. Deacon
Contents Acknowledgements 1 Introduction 1.1 Health and safety considerations 2 The corrosion of steel 2.1 Corrosion: the basic process 2.2 The electrochemical nature of corrosion 2.3 Corrosion terminology 2.3.1 Potential 2.3.2 Polarisation 2.3.3 Passivity 2.4 Corrosion in air 2.4.1 Steel composition 2.4.2 Rust 2.5 Corrosion in water 2.5.1 Composition of water 2.5.2 Operating conditions 2.5.3 Steel composition 2.5.4 Corrosion rates of steel in water 2.6 Corrosion in soil 2.7 Bacterial corrosion 2.8 Health and safety considerations References Further reading 3 Surface preparation 3.1 Steel surface contaminants and conditions 3.1.1 Oil and grease © 2002 D. A. Bayliss and D. H. Deacon
3.1.2 Millscale 3.1.3 Surface cleanliness 3.1.4 Roughness 3.1.5 Surface defects and welds 3.2 Surface preparation methods 3.2.2 Hand-and power-tool cleaning 3.2.3 Abrasive blast-cleaning 3.2.4 Innovative methods 3.2.5 Flame cleaning 3.2.6 Pickling 3.2.7 Iron and zinc phosphating 3.3 Health and safety matters 3.3.1 General 3.3.2 Open nozzle blast-cleaning 3.3.3 Pressure water jetting 3.3.4 Flame cleaning Paints and paint coatings 4.1 General requirements 4.2 The nature of paint 4.2.1 Paint systems 4.3 Protection by paint films 4.3.1 Zinc-rich pigments 4.3.2 Inhibitive pigments 4.3.3 Barrier coatings 4.4 Properties of paint films 4.4.1 Adhesion 4.4.2 Flexibility 4.4.3 Hardness 4.44 Abrasion resistance 4.4.5 Permeability 4.4.6 esistance to microorganisms 4.4.7 Ageing of paint films 4.5 Paint film formation 4.6 Binders 4.6.1 Oxidation type 4.6.2 Solvent evaporation type 4.6.3 Chemically reacting type C D.A. Bavliss and D. H. Deacon
3.1.2 Millscale 3.1.3 Surface cleanliness 3.1.4 Roughness 3.1.5 Surface defects and welds 3.2 Surface preparation methods 3.2.1 Degreasing 3.2.2 Hand- and power-tool cleaning 3.2.3 Abrasive blast-cleaning 3.2.4 Innovative methods 3.2.5 Flame cleaning 3.2.6 Pickling 3.2.7 Iron and zinc phosphating 3.3 Health and safety matters 3.3.1 General 3.3.2 Open nozzle blast-cleaning 3.3.3 Pressure water jetting 3.3.4 Flame cleaning References 4 Paints and paint coatings 4.1 General requirements 4.2 The nature of paint 4.2.1 Paint systems 4.3 Protection by paint films 4.3.1 Zinc-rich pigments 4.3.2 Inhibitive pigments 4.3.3 Barrier coatings 4.4 Properties of paint films 4.4.1 Adhesion 4.4.2 Flexibility 4.4.3 Hardness 4.4.4 Abrasion resistance 4.4.5 Permeability 4.4.6 Resistance to microorganisms 4.4.7 Ageing of paint films 4.5 Paint film formation 4.6 Binders 4.6.1 Oxidation type 4.6.2 Solvent evaporation type 4.6.3 Chemically reacting type vi Contents © 2002 D. A. Bayliss and D. H. Deacon
4.7 Pigments 4.7.1 Inhibitive pigments 4.7.2 Other pigments 4.7.3 Extenders 4. 8 Solvents 9 Paint classificatio 4.9.1 Oil-based and oleo-resinous paints (oxidation drying) 4.9.2 Solvent evaporation paints 4.9.3 Chemical reaction paints 4.94 Zinc-rich coatings 4.9.5 Waterborne coatings 4.9.6 Compatibility of different paints 4.9.7 Heat-resistant coatings 4.9.8 Other coating materials and fillers 4.10 Health and safety matters References Further reading 5 Paint application 5.1 Methods of application 5.1.1 Brush application 5.1.2 Roller application 5.1.3 Airspray application 5.1.4 Airless spraying 5.1.5 Application of plural-component paints by 5.1.6 Electrostatic spray 5.1.7 Other application method 5.1.8 Comparison of application method 5.2. Application conditions 5.2.1 Pre-or post-fabrication 5.2.2 The painting shop 5.2.3 Ambient conditions 5. 2. 4 Storage of paint 5.2.5 Preparation of paint before use 5.3 The painter 5.4 Paint manufacturers 'data sheets 5.5 Health and safety matters 5.5.1 Airless spray C D.A. Bavliss and D. H. Deacon
4.7 Pigments 4.7.1 Inhibitive pigments 4.7.2 Other pigments 4.7.3 Extenders 4.8 Solvents 4.9 Paint classification 4.9.1 Oil-based and oleo-resinous paints (oxidation drying) 4.9.2 Solvent evaporation paints 4.9.3 Chemical reaction paints 4.9.4 Zinc-rich coatings 4.9.5 Waterborne coatings 4.9.6 Compatibility of different paints 4.9.7 Heat-resistant coatings 4.9.8 Other coating materials and fillers 4.10 Health and safety matters References Further reading 5 Paint application 5.1 Methods of application 5.1.1 Brush application 5.1.2 Roller application 5.1.3 Airspray application 5.1.4 Airless spraying 5.1.5 Application of plural-component paints by spray 5.1.6 Electrostatic spray 5.1.7 Other application methods 5.1.8 Comparison of application methods 5.2. Application conditions 5.2.1 Pre- or post-fabrication 5.2.2 The painting shop 5.2.3 Ambient conditions 5.2.4 Storage of paint 5.2.5 Preparation of paint before use 5.3 The painter 5.4 Paint manufacturers’ data sheets 5.5 Health and safety matters 5.5.1 Airless spray Contents vii © 2002 D. A. Bayliss and D. H. Deacon
5.5.2 Paint materials References 6 Specialist coatings and applications 6.1 Coating or lining of tanks 6.1.1 Corrosion protection 6. 1.2 Lining materials 6.1.3 Application of linings 6.2 Powder coatings 6.2.1 Application methods 6.3 Coil coatings 6.4 Wrapping tapes 6.5 Fire protection 6.6 Pipelines 6.6.1 Subsea pipelines 6.6.2 Buried pipelines References 7 Metal coatings 7.1 Application methods Hot-dipping 7.1.2 Sprayed coatings 7.1.3 Coatings produced by diffusion 7.1.4 Electrodeposited chaun 7.1.5 Other application methods 7.2 Corrosion mechanism of metallic coatings 7.3 Painting of metallic coatings 7.4 Performance of metallic coatings 7.4.1 Performance of zinc coatings 7.4.2 Performance of aluminium coatings 743 Performance of cadmium coatings 7.5 Comparison between metallic and paint coatings 7.6 Choice of type of metallic coatin 7. 7 Treatment of welded areas 7.8 Wet storage st 7.9 Fasteners 7.10 Health and safety matters 7.10.1 Hot-dip galvanising 7.10.2 Metal spraying References C D.A. Bavliss and D. H. Deacon
5.5.2 Paint materials References 6 Specialist coatings and applications 6.1 Coating or lining of tanks 6.1.1 Corrosion protection 6.1.2 Lining materials 6.1.3 Application of linings 6.2 Powder coatings 6.2.1 Application methods 6.3 Coil coatings 6.4 Wrapping tapes 6.5 Fire protection 6.6 Pipelines 6.6.1 Subsea pipelines 6.6.2 Buried pipelines References 7 Metal coatings 7.1 Application methods 7.1.1 Hot-dipping 7.1.2 Sprayed coatings 7.1.3 Coatings produced by diffusion 7.1.4 Electrodeposited coatings 7.1.5 Other application methods 7.2 Corrosion mechanism of metallic coatings 7.3 Painting of metallic coatings 7.4 Performance of metallic coatings 7.4.1 Performance of zinc coatings 7.4.2 Performance of aluminium coatings 7.4.3 Performance of cadmium coatings 7.5 Comparison between metallic and paint coatings 7.6 Choice of type of metallic coating 7.7 Treatment of welded areas 7.8 Wet storage stain 7.9 Fasteners 7.10 Health and safety matters 7.10.1 Hot-dip galvanising 7.10.2 Metal spraying References viii Contents © 2002 D. A. Bayliss and D. H. Deacon
8 Writing effective specifications 8.1 Scope of the specification 8.1.1 Scope 8.1.2 Documents 8.1.3 Pre-job conference 8.1.4 Surface preparation 8.1.5 Materials 8.1.6 Control of coating materials and samples 8.1.7 Coating application 8.1.8 Work 8.1.9 Treatments of special areas 8.1.10 Handling, transport and storage 8.1.11 Remedial work 8.1.12 Inspection and quality control 8. 1. 13 Safety 8.1. 14 Other aspects of specifications 8.2 International standards 9 Quality control of coating operations 9.1 Introduction 9.2 Inspection requirements 9.3 The approach to quality control 9.4 Requirements for an inspector 9.4.1 Training and certification of inspectors 9.5 Methods of inspection of paint coatings 9.5.1 Surface preparation .5.2 Testing of liquid paints 9.5.3 Coating application 9.6 Inspection of metal coatings 9.6.1 Hot-dip galva 9.6.2 Sprayed metal coatings 9.7 Inspection instruments 2.8 Reports and records 9.9 Health and safety matters References 0 Designing for corrosion control 10.1 Environmental conditions materials 10.3 Bimetallic corrosion C D.A. Bavliss and D. H. Deacon
8 Writing effective specifications 8.1 Scope of the specification 8.1.1 Scope 8.1.2 Documents 8.1.3 Pre-job conference 8.1.4 Surface preparation 8.1.5 Materials 8.1.6 Control of coating materials and samples 8.1.7 Coating application 8.1.8 Workmanship 8.1.9 Treatments of special areas 8.1.10 Handling, transport and storage 8.1.11 Remedial work 8.1.12 Inspection and quality control 8.1.13 Safety 8.1.14 Other aspects of specifications 8.2 International standards 9 Quality control of coating operations 9.1 Introduction 9.2 Inspection requirements 9.3 The approach to quality control 9.4 Requirements for an inspector 9.4.1 Training and certification of inspectors 9.5 Methods of inspection of paint coatings 9.5.1 Surface preparation 9.5.2 Testing of liquid paints 9.5.3 Coating application 9.6 Inspection of metal coatings 9.6.1 Hot-dip galvanising 9.6.2 Sprayed metal coatings 9.7 Inspection instruments 9.8 Reports and records 9.9 Health and safety matters References 10 Designing for corrosion control 10.1 Environmental conditions 10.2 Materials 10.3 Bimetallic corrosion Contents ix © 2002 D. A. Bayliss and D. H. Deacon
10.4 Access for inspection and maintenance 10.5 Crevices 10.6 Ground-level corrosion 10.7 Entrapment of moisture and condensation 10.8 Geometry and shape 10.9 Tanks 10.10 Fabrication and construction 10.11 Corrosion of steel in contact with other materials Further reading lI Maintenance painting 11.1 Introduction 11.2 The general approach to maintenance painting 11.3 Planning maintenance 11.4 Inspections and surveys for maintenance 11.4.1 Survey procedures 11.4.2 Feasibility trials 11.5 Maintenance procedures 11.5.1 Surface preparation prior to repainting 11.5.2 Painting 11.6 Environmental conditions during repainting 11.7 Health and safety matters 12 Control methods other than coatings 12.1 Cathodic protection 12.1.1 Basic principles 2.1.2 The application of cathodic protection 12.1.3 Sacrificial anode method 12.1.4 Impressed current method 12.1.5 Choice of method for cathodic protection 12.1.6 Practical applications of cathodic protection 2.1.7 Coatings and cathodic protection 2.2 Conditioning of the environment 12.2.1 Treatment of the air 12.2.2 Treatment of aqueous solutions 2.3 Alloy steels 12.3.1 Stainless steels 12.3.2 Low-alloy weathering steels References C D.A. Bavliss and D. H. Deacon
10.4 Access for inspection and maintenance 10.5 Crevices 10.6 Ground-level corrosion 10.7 Entrapment of moisture and condensation 10.8 Geometry and shape 10.9 Tanks 10.10 Fabrication and construction 10.11 Corrosion of steel in contact with other materials Further reading 11 Maintenance painting 11.1 Introduction 11.2 The general approach to maintenance painting 11.3 Planning maintenance 11.4 Inspections and surveys for maintenance 11.4.1 Survey procedures 11.4.2 Feasibility trials 11.5 Maintenance procedures 11.5.1 Surface preparation prior to repainting 11.5.2 Painting 11.6 Environmental conditions during repainting 11.7 Health and safety matters References 12 Control methods other than coatings 12.1 Cathodic protection 12.1.1 Basic principles 12.1.2 The application of cathodic protection 12.1.3 Sacrificial anode method 12.1.4 Impressed current method 12.1.5 Choice of method for cathodic protection 12.1.6 Practical applications of cathodic protection 12.1.7 Coatings and cathodic protection 12.2 Conditioning of the environment 12.2.1 Treatment of the air 12.2.2 Treatment of aqueous solutions 12.3 Alloy steels 12.3.1 Stainless steels 12.3.2 Low-alloy weathering steels References x Contents © 2002 D. A. Bayliss and D. H. Deacon
13 Coating defects and failures 13.1 Introduction 13 Surface preparation Coating materials 13. 4 Coating application 13.5 Transport and storage 13.6 Types of coating defects 13.6.1 Adhesion loss(flaking, peeling, etc. 13.6.2 Bacterial or fungal attack 13.6.3 Bleeding 13. 6.4 Blistering 13.6.5 Blooming or blushing 13.6.6 Chalkin 3.6.7 Cissing, crawling and fisheyeing 13.6.8 Cobwebbing 13. 6.9 Cracking 13.6. 10 Complete or partial failure to cure of two-part materials 3.6.11 Dry spray 13. 6.12 Fading 13.6.13 Lifting or pulling up 13.6. 14 Orange peel 13. 6.15 Pinholes and holidays 13.6.16 Pinpoint rustin 13.6. 17 Runs and sags 13. 6.18 Saponification 13.6.19Skin curing 13.6. 20 Spot-blast boundary breakdown 13.6.21 Thickness faults 13.6.22 Uneven gloss 13.6.23 Undercutting 13. 6.24 Wrinkling References 14 The selection of coating systems 4.1 Introduction 14.2 Factors influencing the selection of coating systems 14.3 Selection of coatings for specific environments 14.4 Types of coatings 14.5 Costs of protective systems C D.A. Bavliss and D. H. Deacon
13 Coating defects and failures 13.1 Introduction 13.2 Surface preparation 13.3 Coating materials 13.4 Coating application 13.5 Transport and storage 13.6 Types of coating defects 13.6.1 Adhesion loss (flaking, peeling, etc.) 13.6.2 Bacterial or fungal attack 13.6.3 Bleeding 13.6.4 Blistering 13.6.5 Blooming or blushing 13.6.6 Chalking 13.6.7 Cissing, crawling and fisheyeing 13.6.8 Cobwebbing 13.6.9 Cracking 13.6.10 Complete or partial failure to cure of two-part materials 13.6.11 Dry spray 13.6.12 Fading 13.6.13 Lifting or pulling up 13.6.14 Orange peel 13.6.15 Pinholes and holidays 13.6.16 Pinpoint rusting 13.6.17 Runs and sags 13.6.18 Saponification 13.6.19 Skin curing 13.6.20 Spot-blast boundary breakdown 13.6.21 Thickness faults 13.6.22 Uneven gloss 13.6.23 Undercutting 13.6.24 Wrinkling References 14 The selection of coating systems 14.1 Introduction 14.2 Factors influencing the selection of coating systems 14.3 Selection of coatings for specific environments 14.4 Types of coatings 14.5 Costs of protective systems Contents xi © 2002 D. A. Bayliss and D. H. Deacon
14.5.1 Calculating the costs of alternative protective systems 14.5.2 Initial costs of protective systems urther reading 15 Protective systems for different situations 5.1 General steelwork exposed to the atmosphere 15.1.1 Bridges 15.1.2 Buildings 15.1.3 Storage tanks(exterior) 15.2 Offshore structures 15.2.1 Atmospheric zone 15.2.2 Immersed zone 5.2.3 Splash zone 15.3 Ships 15.3.1 Surface preparation 15.3.2 Areas to be protected 15.3.3 Underwater plating 15.3.4 Anti-fouling paints 15.3.5 Boot te 15.3.6 Topsides and superstructures 15.3.7 Steel decks 15.3.8 Machinery, pipes, etc 5.3.9 Cargo and ballast tanks 5.3.10 Freshwater tanks 15.4 Chemical plants 5.5 Oil refineries and installations 15.6 Sewage systems 15.7 Sheet piling 15.8 Jetties and harbours 15.9 Steel in reinforced concrete 15.9.1 Concrete 15.9.2 The corrosion of rebar in concrete 5.9.3 Types of failure with reinforced concrete 5.9.4 Corrosion control methods 16 Testing of coatings 16.1 Introduction 16.2 Test requirements C D.A. Bavliss and D. H. Deacon
14.5.1 Calculating the costs of alternative protective systems 14.5.2 Initial costs of protective systems Further reading 15 Protective systems for different situations 15.1 General steelwork exposed to the atmosphere 15.1.1 Bridges 15.1.2 Buildings 15.1.3 Storage tanks (exterior) 15.2 Offshore structures 15.2.1 Atmospheric zone 15.2.2 Immersed zone 15.2.3 Splash zone 15.3 Ships 15.3.1 Surface preparation 15.3.2 Areas to be protected 15.3.3 Underwater plating 15.3.4 Anti-fouling paints 15.3.5 Boot topping 15.3.6 Topsides and superstructures 15.3.7 Steel decks 15.3.8 Machinery, pipes, etc. 15.3.9 Cargo and ballast tanks 15.3.10 Freshwater tanks 15.4 Chemical plants 15.5 Oil refineries and installations 15.6 Sewage systems 15.7 Sheet piling 15.8 Jetties and harbours 15.9 Steel in reinforced concrete 15.9.1 Concrete 15.9.2 The corrosion of rebar in concrete 15.9.3 Types of failure with reinforced concrete 15.9.4 Corrosion control methods References 16 Testing of coatings 16.1 Introduction 16.2 Test requirements xii Contents © 2002 D. A. Bayliss and D. H. Deacon
