Industrial Ceramics offers One End Closed Thermocouple Protection Tubes. Industrial Ceramics supplies technical ceramics. One End Closed Thermocouple Protection Tubes has been available in the size range from 6mm OD to 44mm OD [smaller OD as well as larger OD up to 200mm can be taken up on request]. One End Closed Thermocouple Protection Tubes is available in the length up to 1500 mm regular size. Thermocouple tubes are slip cast i.E. The whole tube is made in one piece including the closed end. The joint becomes the weak spot failure which generally occurs at that joint. It is used for thermocouple sensors and up to 1800 degree centigrade.