Development of the high grade industrial platinum resistance thermometers at NMIJ - A review of what has been revealed

摘要

There is a demand for thermometers that is an intermediate solution between the so called standard thermometers and the industrial thermometers, in both scientific use and industrial use. To seek for such solution, the National Metrology Institute of Japan (NMIJ, AIST) has been undertaking the development of PRTs for a more precise temperature measurement upon collaboration with the manufacturers. In this presentation, we review the development of "high grade" industrial PRTs, which are aimed to be an intermediate solution between the standard PRTs and the conventional industrial PRTs during these 20 years. The most important developments are the alumina insulating high-temperature IPRTs, and the stainless sheathed small sized IPRTs that have improved stability. We review and summarize the various findings in our publications, as well as listing the possible impact and applications of the developments. We also state some of our underlying concepts in our development.