The TCT 426 works according to the hot wire method and is especially designed for the investigation of refractory rock. The measuring cross, parallel wire, and T(R) methods can be used in the instrument. The TCT 426 is indispensable for the efficient use of energy in industrial kiln engineering with refractories.
Thermal conductivity and thermal diffusivity are the most important thermophysical parameters for characterization of the thermal transport properties of a material or component.
The hot-wire method is an absolute method for direct determination of the thermal conductivity, based on the measurement of the temperature increase of a linear heat source/hot wire (cross-wire technique, according to ISO 8894-1) or at a specific distance from a linear heat source (parallel-wire technique, according to ISO 8894-2).
The hot wire and thermocouple are embedded between two test pieces, which make up the actual test assembly. The time-dependent temperature increase after the heating current is switched on is a measure of the thermal conductivity of the material being tested.
Another variation, the so-called "Platinum Resistance Thermometer Technique" or "T(R) Technique", is described in ASTM-C 1113. Here an integral temperature measurement is carried out over the entire length of the hot wire; i.e. the hot wire is both heat source and temperature sensor at the same time.
The TCT 426 thermal conductivity tester enables the use of all three of the methods described in easily interchangeable, pre-wired measuring frames.
TCT 426 – Technical Specification
Temperature range in accordance with ISO 8894-1, ISO 8894-2 from RT to 1250°C (higher temperatures up to 1500°C are possible depending on the material)
Chamber-hood furnace with 12 Super-Kanthal heating elements
Heating and cooling rates: 0,01 K/min to 5 K/min
Atmospheres: air, static
Hot-wire capacity: 0.1 to 50 W (continuously adjustable power in 2 zones)
Measurement of the temperature increase with differential thermocouples
Test piece dimensions: 250 mm x 125 mm x 75 mm
(2 test pieces together make up one test assembly)
Measuring frame for cross-wire method and parallel-wire method
Measuring frame for T(R) technique (optional)
