Process Control Basics

Acknowledgments xiii
Preface xvii
About the Author xix

Chapter 1 What Is Process Control? 1
1.1ââWhat Is a Process? 1
1.2ââWhat Is Control? 2
1.3ââWhy Do We Need Process Control? 4
1.4ââHow to Use This Book 7

Chapter 2 Basic Measurements 9
2.1ââGeneral Principles of Measurement 9
2.2ââPressure Measurement 9
2.3ââHow Level Sensors Sense 18
2.4ââHow Flow Sensors Sense 24
2.5ââTemperature Sensors 31
2.6ââRange, Span, and Calibration 36

Chapter 3 Control System Basics 41
3.1ââClosed Loop versus Open Loop Control 41
3.2 Single Loop Controller 43
3.3ââLogic Control, Sequential and Batch Control 44
3.4ââPLC 46
3.5ââDCS 53
3.6ââHybrid Controllers 56
3.7ââEmbedded Controllers 56

Chapter 4 Communications 59
4.1ââBinary Communications 59
4.2ââAnalog Communications 61
4.3ââDigital Communications 64
4.4ââConverting Between Signal Types 66
4.5ââDisplaying Information 68
4.6ââRetaining Data History 71

Chapter 5 Final Control Elements 73
5.1ââControl Valves 74
5.2ââDampers 82
5.3ââActuators 83
5.4 Switches and Positioners 85
5.5ââVariable Speed Drives 86
5.6ââHeaters 88
5.7ââOther Final Control Elements 89
5.8ââRegulators 89
5.9ââLimiting Elements 89

Chapter 6 Continuous Control 93
6.1ââControl Terminology 93
6.2ââOn-Off Control of Continuous Processes 94
6.3ââPID 95
6.4ââSelectors, Overrides, and Interlocks 109
6.5ââAlarms, Messages, and Reports 111

Chapter 7 Logic Control 115
7.1ââBinary Logic Control 116
7.2ââHow Binary Logic Control Works 116
7.3ââBinary Logic Diagramming 121
7.4ââImplementation of Binary Logic Control 124

Chapter 8 Control System Documentation 129
8.1ââProcess Flow Diagrams 129
8.2ââP&ID Drawings 130
8.3ââInstrument Index 132
8.4ââInstrument Specifications 133
8.5ââPiping Diagrams 134
8.6ââControl Narratives 134
8.7ââLoop Diagrams 136
8.8ââLogic Diagrams 136
8.9ââControl Loop Diagrams 136
8.10ââNetwork Diagrams 137
8.11ââFactory and Site Acceptance Tests 138

Chapter 9 Practical Considerations 141
9.1ââMaterials 141
9.2ââPower Supply 142
9.3ââInstrument Location 144
9.4ââAccuracy 144
9.5ââProtecting the Instrument 146
9.6ââMaintenance and Reliability Considerations 147
9.7ââManagement of Change 148
9.8ââCybersecurity 149

Chapter 10 Advanced Sensors and Analyzers 151
10.1ââSensors for Process Fluids 151
10.2ââPhysical and Mechanical Sensors 156
10.3ââAnalyzers 158
10.4ââCombining Measurements: Virtual Sensors 160

Chapter 11 Beyond the Basics of Process Control 163
11.1ââAdvanced Regulatory Control 163
11.2ââModel Predictive Control 169
11.3ââArtificial Intelligence in Process Control 171
11.4ââSafety Instrumented Systems 173
11.5ââDiagnostics and Analytics 173
11.6ââAlarm Management 174

References 175
Abbreviations/Acronyms 177
Bibliography 181
Index 187