Individual electrical/thermal properties
Crushable cores made of magnesium oxide (C820) and porous steatite (C230) are ceramics with deliberately low mechanical strength. They are characterised by good compactability and offer sufficient electrical insulation combined with good thermal conductivity, depending on the application temperature and material composition.
The advantages of our crushable cores
- Extremely tight tolerance ranges enable precise components
- Enormous thermal conductivity up to 60 W/mK
- High electrical insulation 1016Ω/cm
- Porous ceramics are characterised by a wide range of design options
- Customised MgO contents from 90 to 99,75% purity
- Specifically adjustable, variable sintering densities from 2,0 to 3,58 g/cm³
- Optimised grain size distributions (D50 from 7 µm to 35 µm) through internal grinding of our raw materials
- Low hydration tendency through optimised passivation
- Minimal metallic impurities below 2 ppm
High and flexible production capacities ensure maximum flexibility, a steady supply and short lead times.
Through targeted further processing of the porous ceramics, their properties and processing techniques are adapted to the respective applications.
Our many years of expertise are your specific customer advantage. Our experts will be happy to advise you.
Products for electrical heating technology
Our crushing corse with intelligent materials enable you to optimise your processes and avoid unplanned downtime.
Heating cartridges/Coil tube cartridges
Optimal heat transfer even with complex geometries and hard-to-reach areas
Our helical tube cartridges are used in the plastics processing industry, among others, and their delicate design enables optimum heat transfer – even on pipes, profiles and hard-to-reach areas. In hot runner technology for plastic injection moulding, the adapted winding pitch of each cartridge ensures precise control of the energy input. This achieves uniform temperature distribution, high process reliability and maximum efficiency.
Coilheater
Reliable heating technology for industrial applications with high thermal requirements
Our heating systems are used to heat liquids and gases. They employ solid MgO cylinders with precise hole structures that are designed for application temperatures of up to 750 °C. Typical areas of application include flange heaters in the offshore industry, switch heaters and electrical heating systems in buildings and industrial plants. These heating elements can be used to achieve heating outputs of up to 3 kW efficiently and reliably.
Mineral-insulated-/Safety cables
Safe operation even in the event of fire, extreme heat and aggressive media
Our ceramics for mineral-insulated high-temperature cables are designed for use in extreme conditions. They reliably transmit energy or signals – even at temperatures above 1000 °C or in direct contact with aggressive media such as heavy oil or gases. Thanks to our magnesium oxide products, the cables ensure safe signal transmission in the event of fire and high thermal stress (flame-retardant). Thanks to their robust construction, they are particularly resistant to temperature, heat and chemicals – ideal for demanding industrial applications.
Sheathed thermocouples
Robust, flexible and highly resilient for precise measurements in industrial processes
Sheathed thermocouples consist of a special sheath cable made of a heat- and corrosion-resistant metal tube. Between the thermocouple and the outer sheath is a mineral insulation layer made of compacted magnesium oxide (MgO). This design ensures excellent electrical insulation and optimum heat conduction up to approx. 1,300 °C. Thanks to their robust internal construction, sheathed thermocouples are ideal for use under high pressures, vibrations and heavy mechanical loads. Even in demanding industrial environments, they offer a long service life, reliability and measurement accuracy. Thanks to their flexibility and compact design, sheathed thermocouples can be flexibly adapted to different installation situations.
Materialselection
- Magnesium oxide C820 (MgO)
- Densely sintered steatite C221
- Porous steatite C230
Further information on the materials can be found here.
FAQ
Frequently Asked Questions about crushable ceramics
What are crushable ceramics?
Crushable ceramics are porous technical ceramics which, due to their brittle structure, can be deliberately compacted during processing. They are primarily used as electrically insulating, temperature-resistant materials in heating elements, thermocouples and mineral-insulating cables. Compaction creates dense ceramic insulation around heating conductors and thermocouple pairs.
What are crushable ceramics used for?
Crushable ceramics are mainly used in heating and temperature measurement technology. Typical applications include cartridge heaters, coiled tubular heaters, coil heaters, sheathed thermocouples, mineral-insulated cables and safety cables.
Which materials are suitable for crushable ceramics?
Rauschert offers crushable ceramics made from various ceramic materials, including magnesium oxide (MgO), porous steatite C230, and densely sintered steatite C221. These materials differ in properties such as thermal conductivity, electrical characteristics, porosity, and temperature resistance.
Why is magnesium oxide used in cartridge heaters and thermocouples?
Magnesium oxide combines excellent electrical insulation with good thermal conductivity. In cartridge heaters, this enables efficient heat transfer from the heating conductor to the outer sheath, while providing reliable electrical thermal insulation for the heating conductor. In sheathed thermocouples, MgO also provides electrical insulation between the thermocouple wires and the outer metal sheath.
Can the sintered density and MgO-purity be adapted to the application?
Rauschert offers crushable ceramics with different sintered densities and tailored MgO purity levels. This allows properties such as porosity, crushing and compaction behaviour, thermal conductivity and electrical insulation to be tailored to the requirements of the application.
What is the difference between magnesium oxide and porous steatite as crushable ceramics?
Magnesium oxide is characterised in particular by its comparatively high thermal conductivity combined with good electrical insulation. It is therefore frequently used in heating elements subject to high thermal loads.
Due to its higher porosity, Porous steatite C230 has lower thermal conductivity and is suitable for applications requiring greater thermal insulation alongside electrical insulation.
Individuel crushable cores for heating cartridges
Do you need ceramic filling and insulating materials for heating cartridges or thermocouples? Tell us about your requirements for thermal conductivity and electrical insulation. We will provide the right solution for your application.