AS/NZS 62086.2:2002

1 - AS/NZS 62086.2:2002 Electrical apparatus for explosive gas atmospheres-Electrical resistance trace heating-Application guide
4 - PREFACE
5 - CONTENTS
7 - 1 Scope
7 - 2 Normative references
8 - 3 Definitions
8 - 4 Application considerations
8 - 4.1 General
9 - 4.2 Corrosive areas
9 - 4.3 Installation considerations
10 - 4.4 Process temperature accuracy
10 - 4.4.1 Type I
10 - 4.4.2 Type II
10 - 4.4.3 Type III
10 - 5 Thermal insulation
10 - 5.1 General
11 - 5.2 Selection of insulating material
11 - 5.3 Selection of weather barrier (cladding)
13 - 5.4 Selection of economical thickness
13 - 5.5 Double insulation
15 - 6 System design
15 - 6.1 Introduction
15 - 6.2 Purpose of, and major requirement for, trace heating
15 - 6.3 Heat loss calculations
16 - 6.4 Heat-up considerations
18 - 6.5 Heat-loss design safety factor
18 - 6.6 Selection of trace heater
19 - 6.7 Maximum temperature determination
19 - 6.7.1 Maximum workpiece temperature - Stabilized design
19 - 6.7.2 Sheath temperature - Metallic applications
20 - 6.7.3 Sheath temperature - Non-metallic pipe applications
21 - 6.8 Design information
21 - 6.8.1 Design information documentation
22 - 6.8.2 Isometric or heater configuration line lists and load charts
22 - 6.9 Power system
23 - 6.10 Start-up at low ambient temperatures
23 - 6.11 Long cable runs
23 - 6.12 Flow pattern analysis
25 - 6.13 Dead-leg control technique
25 - 6.14 Chimney effect
25 - 7 Control and monitoring equipment
25 - 7.1 General
25 - 7.2 Mechanical controllers
26 - 7.3 Electronic controllers
26 - 7.4 Application suitability
26 - 7.5 Location of controllers
26 - 7.6 Location of sensors
26 - 7.7 Alarm considerations
26 - 7.7.1 General
27 - 7.7.2 Trace-heating circuit alarm
27 - 7.7.3 Temperature alarms
27 - 7.7.4 Other alarms
27 - 7.7.5 Integrated control
28 - 8 Recommendations for installation, testing and maintenance
28 - 8.1 Introduction
28 - 8.2 Application
28 - 8.3 Preparatory work
28 - 8.3.1 General
28 - 8.3.2 Personnel
28 - 8.3.3 Receiving materials
28 - 8.3.4 Warehousing and handling
28 - 8.3.5 Pre-installation testing
29 - 8.3.6 Pre-installation checks
30 - 8.3.7 Scheduling of installation
30 - 8.3.8 Surface preparation
30 - 8.3.9 Component substitution
30 - 8.4 Installation of trace-heating systems
30 - 8.4.1 General
30 - 8.4.2 Bonding to earth
30 - 8.4.3 Terminations
31 - 8.4.4 Cold leads
31 - 8.4.5 Junction boxes
31 - 8.4.6 Cable entries and glands
31 - 8.4.7 Conductor terminations
31 - 8.4.8 Terminal end fittings
32 - 8.4.9 Jointing, splicing and modifications
32 - 8.5 Installation of trace heaters
32 - 8.5.1 General
32 - 8.5.2 Field (work site) tests
32 - 8.5.3 Thermal contact
32 - 8.5.4 Laying
33 - 8.5.5 Fixing and banding
33 - 8.5.6 Additional heat loss compensations
33 - 8.5.7 Protection from leaks
33 - 8.5.8 Damage protection
33 - 8.6 Installation of control and monitoring equipment
33 - 8.6.1 General
33 - 8.6.2 Sensor considerations
34 - 8.6.3 Sensor installation
34 - 8.6.4 Protection against damage
34 - 8.6.5 Exit of sensor from thermal insulation
34 - 8.6.6 Controller housing
34 - 8.6.7 Process temperature controllers
34 - 8.6.8 Other equipment
34 - 8.7 Installation of thermal insulation system
34 - 8.7.1 General
34 - 8.7.2 Preparatory work
35 - 8.7.3 Installation of the thermal insulation materials
35 - 8.7.4 Cladding
35 - 8.8 Commissioning
35 - 8.8.1 Pre-commissioning test
36 - 8.8.2 Trace-heating commissioning
36 - 8.9 Maintenance
36 - 8.9.1 General
36 - 8.9.2 Fault location
36 - 8.9.3 Fault rectification
36 - 8.10 Repairs
36 - 8.10.1 General
37 - 8.10.2 Practicability of repair to electric trace heaters
37 - 8.10.3 Repair techniques for electrical trace heaters
38 - 8.10.4 Earthing
38 - 8.10.5 Testing
42 - Annex ZZ - Variations to IEC 62086-2:2001 for application in Australia and New Zealand
42 - ZZ1 Introduction
42 - ZZ2 Technical variations