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ThermalEx™ – Hazardous Area Heating

  • Jul 10 / 2014
  • 0

ThermalEx™ – Hazardous Area Heating

Vulcanic TEE has been certified by SIMTARS and Sira to design and manufacture IECEx and ATEX certified explosionproof heaters in Australia at Vulcanic TEE’s Coffs Harbour plant in Northern NSW.

Vulcanic TEE’s ThermalEx™ range of IECEx and ATEX certified hazardous area heaters are currently available with Ex ‘d’ certification for Zone 1, Group I and IIb + H2 with IP66 certified weatherproof terminal boxes.
Temperature classifications range from T3-T6 and all elements are specially sealed to prevent moisture ingress. Elements can be replaced individually and easily on site by using double-bite compression fittings to make installation and servicing easier.
The ThermalEx™ range of heaters is constantly expanding, so if you require a heater with specifications outside of this range, please contact us to find out what we can do for you.

Vulcanic TEE are now licensed under Tegas with Petronas! This opportunity will not only open many doors in the South East Asian region but will allow us to better serve our new and existing customers in Malaysia.

View our current certification online:

TIH range
TWIH range

or download the PDF versions:

TIH IECEx certificate
TWIH IECEx certificate
ATEX certificate.

IECEx has a new mobile app available for both Apple and Android users to keep up to date with the certificates for Ex certified companies.
The app gives access to the IECEx Certificate of Conformity system covering Ex Certified Equipment.
Make sure you’re covered by checking that your suppliers certificate is valid.
Available in both online and offline modes so it can be accessed anywhere. Get it now!

The IEC Ex Scheme
The ATEX Directive
Process, Inline & Immersion Heaters
Industrial Ovens
Element End Sealing
ThermalEx™ Heater Assembly
Control Systems
Experience List


ThermalEx heaters are designed for hazardous areas where an explosive atmosphere is present. Hazardous areas can be found in a wide variety of places including oil platforms, mines, petroleum processing, sewage treatment and laboratories to name a few.

Some applications our heaters are often used in:

  • Fuel Gas
  • Natural Gas
  • Mining
  • Industrial Gases
  • Crude Oils ⁄ Hydrocarbon Liquids
  • Fuel Oils
  • Heat Transfer Oils
  • Molecular Sieve Regeneration
  • Knockout Drums and more…

The IECEx Scheme

The IECEx Scheme is a quality based scheme that requires the issue of a Test Report and a Quality Assessment Report (QAR) in order for a Certificate of Conformity to be issued. A QAR is issued on the basis of a successful on site assessment of a manufacturer’s quality system. Surveillance audits of the manufacturer are conducted annually or twice per year. The objective of the International Electrotechnical Commission (IEC) Ex Scheme is to facilitate international trade in equipment and services for use in explosive atmospheres while maintaining the required level of safety. Vulcanic TEE’s IECEx certification assures you that the products we supply are of the highest standards in both safety and design as well as meeting quality assurance standards equivalent to ISO:9001.

For more information on the IECEx certification scheme, visit the IECEx website.


The ATEX Directive

The ATEX directive was primarily created for goods and products sold in the European market, however it is widely accepted in countries around the world. The ATEX directive aims to allow the free movement of goods and products in the European and global community while ensuring quality and safety standards are adhered to across borders, but allowing for a more harmonised certification process.

For more information on the ATEX directive, visit the European Commission website.

Process, Inline & Immersion Heaters

The ThermalEx™ range of certified flanged immersion heaters are currently available with process temperatures up to 450°C. Drawing on Vulcanic TEE’s extensive electric heating element experience, the elements used in these bundles can be a variety of sheaths to suit your specific applications, including Stainless Steel, Titanium, Incoloy and more.
Element lengths can be anywhere from 300mm to 6m depending on your requirements, with varying element quantities within the bundle, giving you the most efficient design.
Flange type is determined by your specifications in order to match your current system or provide the best fit for the heater design.
Options include double-bite compression fittings, control panels, vessels, thermowells and more.


Element End Sealing

The main cause of earth leakage trip issues is moisture ingress through the element ends. This leads to low insulation readings and subsequent element failure over time. To eliminate this problem, Vulcanic TEE uses a twin sealing process on all its ThermalEx™ heaters, which guarantees high insulation resistance readings for years to come.

Vulcanic TEE’s End Sealing Procedure

  • Heating elements are placed into a vertical dehydration oven for a minimum of 48 hours and allowed to completely dry out.
  • Insulation tests are performed and must be greater than 500MΩ before the sealing process is carried out.
  • Sealing process 1 (10mm) is carried out while the heating element is in the hot state (110°C minimum surface temperature).
  • Heating element is placed for the second time into the oven for a minimum of 36 hours.
  • Insulation test performed – >500MΩ minimum reading allowable.
  • Sealing process 2 (5mm) is carried out while the element is in the hot state.
  • Once sealed, insulation and Hi pot tests are performed.

Vulcanic TEE’s in house test results have verified the quality of the twin sealing process and guarantees the reliability and longevity of the unit.

Squeeze test and then immersed in 20-24°C water for 45 minutes – Result: 200MΩ Insulation testEnvironmental chamber test at 90°C. 95% relative humidity for 4 weeks – Result: 200MΩ
Immersed in 20-24°C water for 28 days – Result: 200MΩ
High temperature oven at 125°C for 6 weeks, removed and placed in sub-zero temperatures for 72 hours – Result: 200MΩ


ThermalEx Heater Assembly – Double Ferrule/Double Bite Compression Fitting

For easy individual heater element replacement

Double Ferrule Compression fittings are torque free, self-aligned mechanical grip fittings that are an industry standard for the chemical, bio-technology, semi-conductor, oil and gas industries to name a few. The complete assembly is made up of four parts (body, front ferrule, back ferrule and nut) that offer excellent leak proof performance in vacuum as well as in low and high pressure applications. The back ferrule provides an anti-vibration hold on the heating element and leak-proof sealing is guaranteed at high operating temperatures. The two ferrule design offered provides a leak-proof seal at three separate points and can adjust to temperature cycling while eliminating damage to the element sheath normally caused by inferior fittings.

  • The heater element is inserted into the process flange or Ex ‘d’ enclosure via the four piece Stainless Steel compression fitting.
  • The body of the compression fitting has an NPT thread that is designed for high pressure applications.
  • The general arrangement and layout of the fitting entry points have been designed so as the integrity of the flange is maintained to the existing design codes.
  • Easy removal and replacement of individual heating elements can be achieved without the need to replace the complete flanged heater bundle.

ThermalEx Heater Assembly – Standoff Flange

For use on Compact High Powered ThermalEx™ Heaters

Tungsten Inert Gas (TIG) welding is highly resistant to corrosion and cracking over long time periods and is ideal for use when working with many of the exotic materials that are required for the Petrochemical, Chemical, Oil and Gas industries. It is the preferred choice when ThermalEx™ heaters are required to be installed into a process area that allows for the maximum kilowatt rating achievable with the minimal space utilised.

  • Thorough cleanliness and preparation are imperative in achieving the best results with numerous inspections and quality checking performed before a single weld is committed to.
  • 316SS standoff ferrules are TIG welded into the process flange or base of the ThermalEx™ enclosure that guarantee a high quality, strong and clean weld to prevent the occurrence of oxidisation.
  • All element ends are heat treated and normalised numerous times prior to being TIG welded or silver brazed into position. This process relieves stress on all element to ferrule contact points ensuring stress fractures do not occur during the assembly and most importantly at the customers process facility.
  • Various exotic flange and ferrule materials are available to suit customers requirements.
  • The general arrangement and layout of the ferrule⁄element entry points have been designed so as to maintain the integrity of the flange and to comply with existing design codes and pressures.

Industrial Ovens

Vulcanic TEE’s popular industrial ovens are also available certified for hazardous areas. ThermalEx hazardous area ovens are available in temperatures up to 450° and can be custom designed to suit your specific needs. We also offer a range of standard sizes to suit 4, 8 and 16 drums.
All of our ovens can be made weatherproof and lockable, giving you more than just a highly efficient heating unit.
Contact us to find out more about our new hazardous area oven range or check out our safe area ovens.



Vulcanic TEE can supply vessels of all shapes and sizes to suit your certified heaters. As part of our complete solution for hazardous area heating, vessels are available for all ThermalEx heaters in a variety of materials, including:

  • Carbon Steel
  • Low Temperature Steel
  • Various ranges of Stainless Steel
  • Duplex and Super Duplex Stainless Steel
  • Hastelloy
  • Zirconium
  • Titanium
  • Nickel Alloys

Vessels are designed in accordance with the following codes:

  • AS1200 – AS1210 – AS1228
  • AS1170 – AS1554 – AS1665
  • AS3992 – AS4037
  • ASME Section VIII. Div 1 and 2
  • PD5500 ⁄ BS5500

Vessels are currently pressure tested to 206 bar ⁄ 3000 psi


Control Systems

The operation of an electric heater is only as good as its control system, therefore a tailor made, first class control system is offered by Vulcanic TEE with a range of options from the simple on⁄off control, to the most sophisticated burst fire⁄single cycle thyristor control.
Load splitting requirements can be divided into stages to give multi-thyristor control and in addition, combinations of thyristor and contactor control can be supplied to provide a fully synchronised system and limit impact on the power generation system.

Vulcanic TEE offers a total control system service including:

  • Thyristor control system design
  • Factory testing and quality control
  • Step contactor sequence control
  • Documentation
  • PLC programming
  • Spares and after sales service
  • Engineering planning
  • Ingress Protection up to IP66 (IEC), NEMA 4X (NEC)
  • Manufacture
  • Suitable for outdoor installation

In-House Testing – in compliance with IEC439-1:1992 AS3439.1-1993

  • Full load⁄Heat Soak Testing
  • Harmonic Analysis
  • RF Interference Testing
  • Dielectric Checks – including HV Test with 500⁄1000V Megger Test before and after
  • Visual Checks – including all labels and door earths
  • Mechanical Checks – including mechanical interlock operation checks
  • Electrical checks – including MCCB⁄ACB setting, Fuse and conductor ratings, functionality and overloads

Flameproof Control Panels

Flameproof control panels can be supplied by Vulcanic TEE. To enable local control of ThermalEx™ hazardous area heaters these control panels are an ideal solution.


  • EEx ‘d’ IIB T1 to T6 Zone 1 & 2 to IP65 (in accordance with IEC529)
  • From -20 to +40°C
  • Marine grade aluminium cast alloy


Experience List

The following products have been manufactured and supplied by Vulcanic TEE as part of the ThermalEx® range

Date Project Name Product Rating Country
2017 Oil Immersion Heater 415V 330kW 3 phase Oil Immersion Heater IECEX Ex’d, Zone1, IIA, T3, IP66 Australia
2017 Water Tank Heater 240V 2300W IECEX Certified Water Bath Heater Ex’d, Zone 1, IIB+H2 T3, IP66 Australia
2016 Oil Bath Vaporizer 240VAC 4800W 2 Stage Ext D Flanged Immersion Heater Australia
2016 Explosion Proof Flanged Oil Tank Heaters 415v 35kW Oil Tank Immersion Heater 200NB ANSI Ex style PNG
2016 Wash Liquor Tank Heater 415V, 11kW, 15.5A, 50Hz Star Connect single stage IECEx Ex’d, IIB, Gb, T3, IP66 Australia
2016 P144 – Gastec – Ex’d air heater Certified Ex air heater 400VAC 3 phase 13kW IECEx Ex’d Zone 2, IIB+H2 T3 Malaysia
2016 CO² Electric Heating Bundle – GNPOC IECEx CO² Electric Heating Bundle – GNPOC Ex d Zone 1 IIB T3 Gb IP66 -20C Sudan
2016 Agitating Hot Tank 2 x 415V 12kW Star Connect IECEx Ex’d IIB+H2 T* Gb IP66 Australia
2015 Petronas Gas Berhad (PGB) 2 x 415V 27kW Single Stage 50-60Hz IECEx PGB Heater IECEx Ex’d, IIB+H², Gb, T3, IP66 Malaysia
2015 Jemena EPG Expansion Project 2 x 400v (3Ph), 76 & 82kW Fuel Gas Heater Bundles Ex’d’ Gas Group IIA T3 IP66 Australia
2015 Shell Australia 2 x 415V 3 phase 4kW withdrawable oil IECEx certified immersion heaters IECEx Ex’d IIB, T3, Gb, IP66 Australia
2015 Shell Miri Malaysia 415V 15kW IECEx Certified Fuel Gas Heater Bundle Ex ‘d’ Gas Group IIB_H2 T3 IP66 Malaysia
2015 Googong Water 2 x 240/415V 22kW SS finned air IECEx d certified hazardous
area duct heaters inserts
Ex ‘d’ Gas Group IIC T6 IP66 Australia
2015 Stolway 1 x 400v 3Ph 28.5kW Flanged Water Immersion Heater
Ex ‘d’ Gas Group IIB+H2 T3 IP66 Australia
2015 Gas facility 1 x 240V 1.5kW Fuel Gas Heater Bundle Ex ‘d’ Gas Group IIA T3 IP66 Australia
2015 Esso Mackerel Platform 1 x 415V 28.8kW 1 stage flanged immersion heater Ex ‘d’ Gas Group IIB+H2 IP66 Australia
2014 Jemena EPG Expansion 2 x 400V, 76 & 80kW Fuel Gas Heaters Ex ‘d’ Gas Group IIA T3 IP66 Australia
2014 Gas Facility 415V 10.8kW Fuel Gas Heater Bundle & Controls Ex ‘d’ Gas Group IIA T3 IP66 Australia
2014 Pulp & Chemical Plant 415V 7.2kW Enclosed Heating Jacket Ex ‘d’ Gas Group IIB Gb T4 IP66 Australia
2014 Hydraulic Oil Heater 2 x 480V 2.8kW Units Ex ‘d’ Gas Group IIB Gb T3/4 IP66 Australia
2014 New Plymouth 415V 15kW Fuel Gas Heater Ex ‘d’ Gas Group IIB T3 IP66 New Zealand
2014 Halibut Platform 415V 28.8kW Flanged Water Heater Ex ‘d’ Gas Group IIB T3 IP66 Australia
2014 TransAlta Solomon Dampier Bunbury Pipeline 2 x 415V 200kW Natural Gas Heater Bundle & Panel Ex ‘d’ Gas Group IIA T3 IP66 Australia
2014 Kleenheat Gas Facility 415V 3kW Immersion heating assembly Ex ‘d’ Gas Group IIB + H2 T3 IP66 Australia
2013 Maitland Gas Facility 415V 4.8kW Fuel Gas Heater Ex ‘d’ Gas Group IIA T3 IP66 Australia
2013 Wallumbilla Compression 215kW 400⁄3⁄50 Turbine Fuel Gas Heater Bundle Ex ‘d’ Gas Group IIA T3 IP66 Australia
2013 Dulux Tank Heating 2 x 415V 12kW Immersion Tank Heaters Ex ‘d’ Gas Group IIB T3 IP66 Australia
2013 Gorgon Barrow Island 415V 11kW Fuel Gas Heater Ex ‘d’ Gas Group IIB+H2 T6 IP66 Australia
2013 Drum Heating 415V 15kW 16 Drum Industrial Oven Ex ‘d’ Gas Group IIB T3-T6 IP66 Australia
2013 PPD Injection Tanks 240⁄415V 3kW Heater bundle Ex ‘d’ Gas Group IIB IP66 Singapore
2013 Plastics and Resins Plant 3 x 415V 10kW Over the Side immersion Ex ‘d’ Gas Group IIB T3 IP66 Australia
2013 Gladstone LNG (GLNG) 415V 10.5kW Hydrate Injection Heater Bundle Ex ‘d’ Gas Group IIB T3 IP66 Australia
2013 Water Plant 2 x 415V 200kW Flanged immersion Ex ‘d’ Gas Group IIB T3 IP66 Australia
2013 Moomba Gas Station 2 x 215kW Turbine Fuel Gas Heaters Ex ‘d’ Gas Group IIA T3 IP66 Australia
2013 Ethanol Distillation Plant 230V 3kW Heating Bundle Ex ‘d’ Gas Group IIA T3 IP66 New Zealand
2013 Offshore Rig 415V 90kW Flanged Heating Bundle Ex ‘d’ Gas Group IIB T3 IP66 Australia
2012 Pilot Plant 240V 1.2kW Heater Ex ‘d’ Zone 2 Group IIB T3 IP66 Australia
2012 Silica Gel/CO2 Heating Plant 415V 6kW Flanged heating assemblies Ex ‘d’ Zone 2 Group IIB + H2 T3 Australia
2012 Seal Gas Supply 415V 7.5kW Flanged heater bundle Ex ‘d’ Group IIB T3 New Zealand
2012 Pilot Plant – Bluescope Steel Mill Glenbrook 10kW Heater Bundle Ex ‘d’ Group IIB T3 IP66 Gb New Zealand
2012 De-oxygenation Laboratory Project De-oxygenation Heater Ex ‘d’ Group IIB T3 Australia
2012 Fertiliser Plant Immersion Heater Ex ‘d’ Group IIB T3 IP66 Gb Australia

The following products were supplied in conjunction with other heater manufacturers

Date Project Name Product Rating Country
2010 Fertiliser Plant Removable Core Immersion Heater Ex ‘d’ Group IIC T3 A21 IP66 Australia
2008 775 TRU Energy Immersion Heaters Ex ‘d’ Group IIC T4 A21 IP66 Australia
2008 777 TCI Sanmar Project Immersion Heaters ATEX Ex II 2 G Ex ‘d’ Group IIC T4 Zone 1 Australia
2008 130kW Thermal Oil Heaters with Control Panels Ex ‘e’ Group II T3 Australia
2007 Perenco FPSO 85kW Fuel Gas Heater with Control Panel and Vessel Ex ‘e’ Zone 1 Group II T3 Australia
2007 Immersion Heaters Ex ‘d’ Group IIC T4 IP66 Australia
2007 Immersion Heaters ATEX Ex ‘d’ IIG/D T4 Zone 1/2 IP65 Australia
2007 Alinta Cogeneration Plant 20kW Oil Tank Heaters with Control Panels Ex ‘d’ Group IIC T4 IP66 Australia
2006 Jingemla Oil Production Facility 11kW Immersion Heater Ex ‘d’ Group IIC T4 IP65 Australia
2006 Shedden 40kW Fuel Gas Heater with Control Panels ATEX II 2 Ex ‘e’ Group IIC T3 Australia
2006 Maitland LNG 10.2kW Fuel Gas Heater with Control Panels Ex ‘e’ Australia

You can also view Vulcanic TEE’s white paper on the use of IECEx certification in hazardous area heating, by downloading the PDF.