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Electric Heating Resistors for Diathermic Oil Circuits

Diathermic (thermal) oil circuits carry high-temperature heat (up to 300 °C and above) to industrial processes such as calenders, presses, extruders and reactors, keeping the loop closed and at low pressure compared with steam. Resistors dedicated to these circuits work at an even lower power density than lubricating-oil heaters, to avoid degrading the heat-transfer fluid over time, and always require a safety flow switch: the boiler must never be energised without oil circulation.

  • Very conservative power density to preserve the service life of the diathermic oil at high temperature
  • Mandatory safety flow switch: no heating without fluid circulation
  • Typically mounted on-board a diathermic oil boiler, with individually replaceable cartridges
  • ATEX certification when the plant handles oil vapours near the flash point
  • Typical use: plastics calenders and presses, chemical reactors, high-temperature drying plants

The technical drawing below shows an example configuration: use the guided configurator to tell us the power, length, dimensions and operating temperature of your diathermic oil circuit.

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Illustrative example

Intended use: Diathermic oil

The values shown in the drawing are an indicative reference to help you read the technical diagram: they do not correspond to a real model, price or product specification.

TECHNICAL DIAGRAM — DIATHERMIC OIL ILLUSTRATIVE EXAMPLE — indicative values, not a real product specification PUMP ATEX POWER 18 kW LENGTH 2200 mm DIMENSIONS Ø 48 mm, flangia DN65 OPERATING TEMP. 320 °C Generic technical drawing, not to scale — actual dimensions will be confirmed in the quote.

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Electric Resistor Configurator

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Frequently asked questions

Diathermic oil circuits carry high-temperature heat, up to 300 °C and above, to industrial processes such as calenders, presses, extruders and reactors, keeping the loop closed and at low pressure compared with steam.
A diathermic oil boiler must never be energised without oil circulation: the safety flow switch is mandatory and is the main protection against the heater running dry.
Diathermic oil heaters work at an even lower power density than lubricating-oil heaters, to avoid degrading the heat-transfer fluid over time; they are typically mounted on-board a boiler with individually replaceable cartridges, with ATEX certification when the plant handles oil vapours near the flash point.