Definition and general information
Screw plug immersion heater are designed to heat liquids (water, oil, heavy fuel oil, glycol, etc.) or gases (air, nitrogen, CO2, etc.) statically in a tank or container, or by forced convection in a circulating fluid heater. They consist of a compact bundle of tubular heating elements, usually pin-shaped, available in various materials compatible with the fluids to be heated. The sealed shielding of the heating elements provides mechanical protection and protection against corrosion.
The heating elements are brazed or welded onto a threaded plug, allowing the immersion heater to be screwed onto a container equipped with a threaded sleeve. This connection allows for a sealed installation up to a maximum of 25 bar.
Screw plug immersion heater be equipped with safety or control devices (probes, thermocouples, thermostats) and a protective connector box.
- Unit power up to 72 kW, max. voltage 750 V (three-phase). Single- or three-phase power supply.
- Reduced inertia and maximum efficiency, as the heating elements are in direct contact with the fluid.
- Easy to install and maintain.
- Wide choice of stocked, ready-to-use products, with short delivery times available from our online catalog.
- Numerous configuration options: wattage, voltage, immersion length, resistor and plug material, plug thread Ø, etc.
Implementation
Applications
Screw plug immersion heater are used Screw plug immersion heater a wide range of applications: energy, marine, automotive, petrochemical, aerospace, processing industries, etc. Below are a few examples of their use:
Food industry
Water heating in poultry scalding tanks. Scalding is an essential step in the poultry slaughtering process, ensuring good plucking results.
Automotive
Oil heating for filling stations for gearboxes and engines. Oil heating reduces viscosity and facilitates pumping.
Marine
Hot water supply on ships.
Energy sector
Temperature maintenance of glycol water in cooling circuits
Technical data
Screw plug immersion heater of:
- Shielded electrical resistors make up the heater core of the immersion heater. Their quantity and diameter (8, 10.2 or 16 mm) vary according to the size of the fixing plug. Several materials are available (Inox 321, Inox 316L, Inox 904L, Incoloy 825®, Incoloy 800®). Heating elements can be straight, shaped as single or double pins.
- The fixing plug is a threaded connection to ISO metric standard (M45 or M77) or cylindrical gas standard (1'' to 2''1/2). Other standards and thread diameters available on request. The plug is fitted with a hexagon to facilitate tightening when installing the immersion heater.
- Electrical terminals for immersion heater power supply. Several terminal models available (threaded, with holes, flat, Faston) or direct wire outputs.
- The thermowell (optional) enables the installation of a safety or control device (probe, thermocouple or thermostat) for measuring fluid temperature, or a heating resistor. It consists of a sealed tube on the fluid side, open on the connector side to allow insertion of the measuring element.
- The offset base is designed for mounting an enclosure to protect the connectors when they are offset. The offset is justified when the temperature of the fluid to be heated exceeds 110°C, to prevent overheating at the terminals.
Further information
- Screw plug immersion heater designed, manufactured, and tested to meet the essential safety requirements of PED 2014/68/EU. They can therefore be installed on vessels subject to PED (Pressure Equipment Directive) up to risk category I, within the applicable PS, TS max, and TS min limits.
- Vulcanic offers ATEX and/or IECEx certified immersion heaters for potentially explosive atmospheres. For surface industries, for use in risk zones 1 and 2, and for temperature classes from T1 to T6.
- In addition to a wide range of standardized finished products shown in our online catalog, Vulcanic can design custom-made equipment, manufactured on demand to meet your specific needs.
- If requested in advance, Vulcanic can supply, in addition to the instruction manual, a number of documents with the equipment (product drawing, 2.1 or 3.1 material certificates, hydraulic and electrical test reports, welding logbook, EU certificate of conformity, etc.).
Recommendations
Precautions for use
When heating a liquid, install the immersion heater in such a way that the heating section is constantly submerged. Otherwise, there is a risk of overheating and destruction of the equipment. The liquid level must be continuously monitored.
In the case of installation in a circulating heater, before switching on the power, the direction of circulation must be checked, purging must be carried out to eliminate air pockets, and the recommended minimum flow rate must be ensured.
In the case of circulating gas heating, it is essential to constantly monitor the flow of gas to be heated. This is particularly important when the power supply is disconnected. The gas flow must be maintained until the heating elements have cooled down completely.
Installation and connection
Horizontal mounting (+/-15°) is preferred. In the case of vertical mounting, the junction box should preferably be placed at the bottom. In the case of vertical mounting with the junction box in the upper part, monitor the temperature of the junction box.
Please refer to the instruction manual for all recommendations relating to the equipment.
Please refer to the instruction manual for all recommendations relating to the equipment.
