Table of Contents
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AS 4426-1997 THERMAL INSULATION OF PIPEWORK, DUCTWORK AND EQUIPMENT - SELECTION, INSTALLATION AND FINISH
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PREFACE
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CONTENTS
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SECTION 1 SCOPE AND GENERAL
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1.1 GENERAL
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1.1.1 Scope
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1.1.2 New designs and innovations
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1.2 REFERENCED DOCUMENTS
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1.3 DEFINITIONS
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1.3.1 Castable cement insulating material
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1.3.2 Coating
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1.3.3 Finishing materials
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1.3.4 Flexible insulating material
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1.3.5 Gypsum plaster
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1.3.6 Hard-setting composition
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1.3.7 Mastic
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1.3.8 Metal cladding, sheathing
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1.3.9 Mineral fibre
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1.3.10 Plastic insulating and finishing materials
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1.3.11 Preformed insulating material
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1.3.12 Self-setting cement
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1.4 EXCHANGE OF DESIGN DATA
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1.4.1 Information to be supplied by the purchaser
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1.4.2 Preparation of surfaces
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1.4.3 Plant details
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1.4.4 Types of fittings and supports
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1.4.5 Type of insulation
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1.4.6 Type of finish
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1.4.7 Special service requirements
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1.4.8 Basis on which the thickness of insulation is to be determined
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1.4.9 Information to be supplied by the manufacturer or contractor
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1.4.10 Drawings
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1.5 PRACTICAL DESIGN CONSIDERATIONS
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1.5.1 General
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1.5.2 Clearance between insulation and the surrounding surfaces
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1.5.3 Provision for differential thermal movement
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1.5.4 Insulation support
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1.5.5 Insulation of pipes in ducts and subways
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1.5.6 Insulation for airconditioning ductwork
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1.5.7 Fire hazards
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1.6 TEMPERATURE CLASSIFICATIONS
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1.7 CONTRACTS
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SECTION 2 SELECTION OF INSULATING MATERIALS AND SYSTEMS
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2.1 CHARACTERISTICS OF INSULATING MATERIALS
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2.1.1 Thermal conductivity and thermal resistance
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2.1.2 Physical forms
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2.1.3 Bulk density
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2.1.4 Suitability for service temperature
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2.1.5 Thermal expansion
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2.1.6 Resistance to compaction
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2.1.7 Resistance to vapour penetration and absorption
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2.1.8 Mechanical strength and durability
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2.1.9 Fire and explosion hazards
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2.1.10 Resistance to vermin and fungus
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2.1.11 Health hazards
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2.1.12 Optimum heat capacity
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2.1.13 Freedom from objectionable odour
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2.1.14 Chemical resistance
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2.2 SELECTION OF THERMAL INSULATING SYSTEMS
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2.2.1 Optimum effectiveness
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2.2.2 Extent of system
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2.2.3 General
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2.2.4 Facts for consideration
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SECTION 3 SELECTION OF SECURING MATERIALS
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3.1 GENERAL
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3.2 ADHESIVES
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3.2.1 General
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3.2.2 Classification according to use
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3.2.3 Application characteristics
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3.2.4 Temperature limits
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3.2.5 Adhesive strength
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3.3 MECHANISM OF CURING
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3.3.1 Solvent-based adhesives
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3.3.2 Chemically curing adhesives
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3.3.3 Hot melt adhesives
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3.4 MECHANICAL SECUREMENTS
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3.4.1 General
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3.4.2 Welded attachments
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3.4.3 Bolted fittings
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3.4.4 Banding and wire securements
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3.5 COMBINATION
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SECTION 4 VAPOUR BARRIERS
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4.1 GENERAL
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4.2 CONDENSATION AND FREEZING
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4.3 REQUIREMENTS FOR A VAPOUR BARRIER
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4.4 VAPOUR BARRIERS FOR USE OVER INSULATION ON SURFACES ABOVE DEW POINT
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4.5 FACTORS WHICH MUST BE CONSIDERED
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4.6 MATERIALS
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SECTION 5 SELECTION AND TREATMENT OF FINISHING MATERIALS
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5.1 GENERAL
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5.2 FINISHING MATERIALS
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5.3 REASONS FOR USE
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5.4 TYPICAL CHARACTERISTICS OF AND USES FOR FINISHING MATERIALS
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5.4.1 General
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5.4.2 Group (a)
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5.4.3 Group (b)
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5.4.4 Group (c)
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5.4.5 Group (d)
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5.5 FINISHES FOR TROPICAL CONDITIONS
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5.5.1 General
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5.5.2 Interior plant in tropical climates
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5.5.3 Outdoor plant in tropical climates
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5.6 FINISHES FOR REFRIGERATION WORK
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5.7 FINISHES TO IMPROVE FIRE PROTECTIVE PROPERTIES
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5.8 FINISHES FOR USE OVER PIPES IN DUCTS AND SUBWAYS, OR BENEATH BUILDINGS
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5.9 ULTIMATE TREATMENT OF FINISH
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5.9.1 General
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5.9.2 Painting as a final finish
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5.9.3 Indoor applications
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5.9.4 Outdoor applications
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SECTION 6 METHODS OF APPLICATION
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6.1 GENERAL
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6.2 SURFACE PREPARATION AND ATTACHMENTS
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6.2.1 Surface preparation
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6.2.2 Attachments
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6.3 INSULATION SUPPORTS
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6.3.1 General
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6.3.2 Stud-type supports
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6.3.3 Cross-sectional area of supports
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6.3.4 Support penetration and thermal bridging
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6.3.5 Finishing material support
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6.3.6 Securement (tie wires, lacing wire, bands, clips, washers and nuts)
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6.3.7 Reinforcement
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6.4 COLD INSULATION: APPLICATION FOR SYSTEMS OPERATING IN THE TEMPERATURE RANGE -75°C TO +10°C
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6.4.1 General
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6.4.2 Adhesives and fastenings
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6.4.3 Typical erection methods
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6.4.4 Pipework and fittings
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6.4.5 Vessels and large curved surfaces
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6.4.6 Airconditioning ductwork (temperature range up to 10°C)
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6.4.7 Flat and irregular surfaces (including machinery)
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6.5 HOT INSULATION: APPLICATION FOR SYSTEMS OPERATING IN THE TEMPERATURE RANGE +10°C TO 800°C
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6.5.1 General
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6.5.2 Pipework
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6.5.3 Flexible materials
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6.5.4 Foamed-in-situ
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6.5.5 Sprayed insulation
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6.5.6 Loosefill insulation
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6.5.7 Insulating concrete
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6.5.8 Pipes with auxiliary heating
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6.5.9 Piping bends
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6.5.10 Flanges, valves and other fittings on hot piping
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6.5.11 Vessels and large curved surfaces
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6.5.12 Airconditioning ducts
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6.5.13 Hot-air ducts (industrial applications) indoor and outdoor
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6.5.14 Gas flues (indoor service)
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6.5.15 Gas flues (outdoor service)
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6.5.16 Flat and irregular surfaces (including machinery)
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SECTION 7 FINISHES-METHODS OF APPLICATION
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7.1 INDOOR FINISHES
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7.1.1 Hard-setting composition or self-setting cement
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7.2 TEXTILE FABRICS
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7.2.1 Woven scrim fabric
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7.2.2 Lightweight canvas and bands
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7.2.3 Heavy fabric wrappings
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7.3 PLASTIC SHEET AND ELASTOMER SHEET
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7.3.1 General
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7.3.2 Rigid sheet
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7.3.3 Flexible sheet
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7.3.4 Removable insulations
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7.3.5 Colour
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7.3.6 Tape
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7.3.7 Preformed materials
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7.4 MASTIC AND COATING FINISHES
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7.4.1 General
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7.4.2 Water-based materials
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7.4.3 Solvent- based materials
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7.4.4 Solvent-free materials
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7.5 METAL SHEET
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7.5.1 General
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7.5.2 Mild steel
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7.5.3 Alloy steel
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7.5.4 Aluminium
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7.5.5 Compatibility
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7.5.6 Sheet thickness
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7.5.7 Application
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7.5.8 Securement
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7.5.9 Vertical pipework
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7.5.10 Flat surfaces
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7.5.11 Surface temperatures
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7.5.12 Board finishes
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7.6 WEATHER RESISTANT FINISHES
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7.6.1 Metal sheet
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7.6.2 Weatherproofing compounds
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7.6.3 Self-setting cement
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7.6.4 Plastic and elastomer sheet
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7.6.5 Roofing felt and wire netting
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7.7 ULTIMATE TREATMENT OF FINISH PAINTING
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APPENDIX A - INSPECTION, TESTING AND MAINTENANCE
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A1 INSPECTION AND TESTING
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A2 SITE MAINTENANCE RECOMMENDATIONS
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APPENDIX B - PROTECTION AGAINST CORROSION
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B1 ELECTROLYTIC CORROSION
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B2 CORROSION, STRESS-CORROSION CRACKING AND LIQUID METAL ATTACK
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B2.1 General
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B2.2 Oxidation
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B2.3 Acidic corrosion
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B2.4 Alkaline corrosive attack
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B2.5 Intergranular corrosion
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B2.6 Bimetallic (galvanic) corrosion
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B3 STRESS-CORROSION CRACKING
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B3.1 Action of water-soluble chlorides on austenitic alloy steels
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B3.2 Stress-corrosion attack on other metals
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B4 ATTACK BY LIQUID METALS
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APPENDIX C - PROTECTION AGAINST CONDENSATION
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C1 PROTECTION AGAINST CONDENSATION
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C1.1 General
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C1.2 Site considerations
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C1.3 Sealing
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C2 CASE DESCRIPTIONS
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C2.1 Sugar mill boiler
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C2.2 Bread-baking oven
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C2.3 Fire-rated bulkhead
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C2.4 Oxygen plant
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C3 VAPOUR BARRIERS
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C3.1 General
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C3.2 Inherent vapour resistance
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C3.3 Barrier performance
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C3.4 Protection from damage
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C3.5 Compatibility
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C3.6 Breather materials
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C3.7 Fire resistance
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C3.8 Application
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C3.9 Below dewpoint operation
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C3.10 Cyclic operation
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APPENDIX D - STANDARDS FOR INSULATING MATERIALS
Abstract
Deals with the selection, installation and finish of thermal insulation for pipework, ductwork, tanks, vessels, and equipment in the temperature range -75C to +800C, but excludes manufactured pre-insulated equipment, structural insulation of buildings and cold stores, fireproofing structures, refractory linings of plant, airborne installations and all external underground mains.
RECONFIRMATION NOTICE
Major stakeholders of this publication have reviewed the content of this publication and in accordance with Standards Australia procedures for reconfirmation, it has been determined that the publication is still valid and does not require change.
Certain documents referenced in the publication may have been amended since the original date of publication. Users are advised to ensure that they are using the latest versions of such documents as appropriate, unless advised otherwise in this Reconfirmation Notice.
Approved for reconfirmation in accordance with Standards Australia procedures for reconfirmation on 29 August 2018.
Scope
This Standard deals with the selection, installation and finish of thermal insulation for pipework, ductwork, tanks, vessels and equipment in the temperature range -75C to +800C but excludes manufactured pre-insulated equipment, structural insulation of buildings and cold stores, fireproofing structures, refractory linings of plant, airborne installations and all external underground mains.
NOTES:
1 The Standard may be found to be generally applicable to the insulation of road and rail transport vehicles and of some assistance in marine insulation.
2 Appendices to the Standard provide guidance on inspection, testing and maintenance (Appendix A), protection against condensation (Appendix B), protection against corrosion (Appendix C) and relevant Australian Standards on insulation materials (Appendix D).
General Product Information
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Published
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Document Type
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Standard |
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Status
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Current |
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Publisher
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Standards Australia
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ProductNote
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Reconfirmed 14/09/2018.
This standard has been reconfirmed in Australia in 2018 and remains current in New Zealand. Reconfirmation Notice 14/09/2018
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Pages
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ISBN
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Committee
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ME-077 |
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Supersedes
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