Use of Chromel-Alumel Thermocouples in High Temperature Experiments in WAGR

摘要

1. Before the prototype Advanced Gas Cooled Reactor at Windscale (WAGR) was finally shut down at the close of its life in June 1981 a programme of concluding experiments, related to certain safety aspects of the Commercial Advanced Gas Cooled Reactors (CAGR), was completed. As part of that programme, some experiments were performed to examine the behaviour of AGR type stainless steel clad fuel pins under postulated operational fault conditions when the peak temperature of the fuel pin cladding approached near to its melting point (1370 deg. C approximately). With this objective, four WAGR fuel stringers were subjected in turn to either a coolant flow or reactor power induced transient lasting a few minutes and sufficient to raise the peak cladding temperature to approximately 1300 deg. C. These experiments were performed in one of the loop systems installed in WAGR which enabled fuel to be irradiated in the reactor core but within a separate pressure tube containment equipped with its own gas cooling system. Thus the in-loop fuel could be operated under temperature conditions different from the rest of the reactor core. 2. This paper is concerned with the thermocouple installation fitted to the experimental stringers to measure the high coolant gas and fuel pin cladding temperatures encountered during the experiments, the method of collecting and checking the data and the performance of the thermocouples during the experiments. (Atomindex citation 14:758840)