Gas Installation Technology - Andrew S. Burcham

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Résumé :

Introduction xi

Acknowledgements xiii

1 The Gas Industry 1

The Gas Industry 1

Nationally Accredited Certification Scheme for Individual Gas Fitting Operatives (ACS) 4

Required ACS Assessments and Flowcharts 9

Legislation Affecting Gas Operatives 10

Specific Legislation Affecting Gas Operatives 15

Industry Documents and British Standards 17

Gas Safety (Installation and Use) Regulations 21

The Future of Gas 24

2 Gas Utilisation 27

Gas: Its Origin 27

Characteristics and Properties of Gases 29

Liquefied Petroleum Gas (LPG) 33

The Combustion Process 34

Air Requirements for Combustion 37

Products of Combustion 39

The Gas Flame 41

Flame Pattern and Characteristics 44

Atmospheric Burners 46

Pre-mix Burners 48

Gas Pressure and Flow 50

Gas Pressure Readings 52

Quick Reference Guide to Taking Pressures 54

Estimating a Suitable Pipe Size 56

Domestic Natural Gas Pipe Sizing 58

Domestic LPG Pipe Sizing 62

Commercial Natural Gas Pipe Sizing 67

Gas Rates and Heat Input 69

Electronic and Smart Meters 72

Quick Reference Tables: Gas Rate/Heat Input 73

The Physical Laws Relating to Gas 76

Measurement of Gas 78

3 Gas Controls 87

Quarter Turn Gas Control Valves 87

Screw Down Gas Control Valves 90

Valve Application 93

Spring-loaded Gas Control Valves 94

Electrically Operated Gas Control Valves 96

Heat-operated Gas Control Valves 98

Pressure-operated Controls Valves 100

Low- and High-pressure Cut-off Devices 102

Pressure Regulators 105

LPG Regulators 108

Flame Supervision Devices 113

Testing Flame Supervision Devices 120

Thermostatic Control 120

Multi-functional Gas Valve 122

Air/Gas Ratio Valve 125

Ignition Devices 127

Vitiation-sensing Devices 129

Pressure and Flow Proving Devices 132

4 Installation Practices 135

Polyethylene Pipe Jointing 135

Copper Pipe Jointing 138

Mild Steel Pipe Jointing 141

Semi-rigid and Flexible Pipe Connections 143

Gas Service and Installation Pipework 145

Connections to High-rise Buildings 150

Gas Meter Installations 153

Commercial Gas Installations 158

Internal Installation Pipework 160

Pipework Laid in Floors 162

Pipework in Walls 165

Pipework Support and Allowance for Movement 168

Timber-framed Dwellings 170

LPG Supply 173

LPG Cylinder Installation 174

Storage and Transportation of LPG Cylinders 176

LPG Bulk Tank Installation 178

Gas Supplies from a Bulk Tank Installation 181

LPG Cylinder Sizing 184

5 Testing and Purging 187

Testing and Purging 187

Tightness Testing With Air (Domestic) 193

Tightness Testing Natural Gas Installations (Domestic) 194

Tightness Testing LPG Installations (Domestic) 199

Purging Domestic Gas Installations 204

Commercial Strength and Tightness Testing (TPCP1A) 209

Commercial Strength and Tightness Testing (TPCP1) 217

Direct Purging Commercial Pipework 230

Indirect Purging Using Nitrogen (N₂) 239

6 Flues and Chimneys 243

Flue/Chimney Classification 243

Chimney/Flue Material and Specification 244

Natural Draught Open-Flue Systems 248

Installation of an Open-Flue Chimney 250

Minimum Open-Flue Heights Domestic ?70 kW 252

>70 kW 254

Open-Flue Terminal Design and Location 258

Condensation within Open-Flue Systems 262