While cryogenic temperature sensors are typically of small size, industrial process plants usually favour thermometers with stainless steel measurement inserts of 3 to 8 mm diameter and arbitrary length. Such thermometers are already in use for cryogenic processes, e.g. at LNG facilities, and it can be expected that they will be adopted for cryogenic systems on a larger scale during the next years.
Many of these thermometers will require frequent (re)calibrations, e.g. for their initial calibration, due to them being used as safety devices, or for research purposes. While these calibrations can easily be facilitated by means of He or L-H2 baths and flow cryostats, such systems have high operating costs and rely on a supply of cryogens. In contrast, dry cryostats typically allow for lower operating costs and easier handling. However, there is currently no known dry cryostat which can accommodate industrial measurement inserts and can be used for their calibration down to liquid hydrogen temperatures.
A cryostat for the calibration of industrial measurement inserts is currently being developed at Technische Universität Ilmenau. It will facilitate the development and calibration of such devices at cryogenic temperatures.
This publication outlines the current design progress, explains key concepts and discusses remaining challenges in the development of the cryostat.

Keywords
Calibration|Instrumentation|Process control|Cryocooler|Thermometry