An essential material testing facility (EMTF) used for pebble bed effective conductivity measuring experiment of high temperature gas-cooled reactor was developed. As required, temperature measuring points were arranged in EMTF to monitor the temperature field. The maximum test temperature in EMTF would be 1600°C. The main part of EMTF was made of graphite and carbon felt, hence the measuring points were in strong carbon reducing environment, of which some were embedded in the carbon felt. The material choice and structure design of the thermal couples were introduced. In the high temperature region, our specially designed tungsten-rhenium thermocouple was used. For the comparison, some imported tungsten-rhenium thermocouples were also used. The distributive data acquisition system was made of IMP form Solartron in England, which with industrial computer constructs a data acquisition and control system. The software was programmed with configuration software of Sunwayland Forcecontrol. Finally, the measuring results in each part of EMTF were given, such as the heater, testing zone, thermal insulating layers. The experimental result showed that the designed temperature measuring system worked stably and reliably, which could finish the temperature acquisition task in 1600°C high temperature carbon reducing condition. After the experiment, the thermal couples experiencing high temperature in carbon reducing condition were removed out to analyze the structural change and study the damaged condition.
Temperature Measuring System of the In-core Components for Chinese 10 MW High Temperature Gas-cooled Reactor
