Table of Contents

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Purpose and Disclaimer v

Acknowledgements vii

Chapter 1: Introduction to Yankee Dryer and Tissue Making 1

Historical Background 1Yankee Dryer Definition 2Corporate Yankee Dryer Safety System 9Safety Management System Key Roles 9Safety Monitoring 11Yankee Dryer Audit 12Risk-Based Safety Management 12

Chapter 2: Engineering and Design Guidelines 13Documentation and Records 13Maximum Allowable Working Pressure 15Head Insulation 16Sensitive Designs 18Interlocks 21

Chapter 3: Inspection Guidelines 25Inspection Guideline Principles 25Inspection Practices 26Nondestructive Examinations 29Routine Periodic Inspections 38Statutory Inspections 49Nonroutine Inspections 50Fitness-for-Service Inspections 51Inspection Monitoring 54

Chapter 4: Operating and Reliability Guidelines 59Operating Limitations 59Warmup 60Cooldown 64Protective Devices 65Dryer Protection from Water Stream and Sprays 66Derating 66Boiler Water Chemistry 68

Table of Contents

Chapter 5: Maintenance and Repair Guidelines 73Repairs and Alterations 73Shell Surface Defect Repair 73Stress Corrosion and Cracking 73Leakage Repairs 74Structural Bolt Tensioning 76Steam Safety Relief Valves 76

Chapter 6: Personnel Protection 79Dryer Entry and Rescue 79Storage 79

Index 81

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