Alumina Ceramic Protection Tubes and Insulator Rods for Thermocouples

Alumina Ceramic has a maximum service temperature of 1700°C or 3090°F in both oxidizing and reducing atmospheres. Thermocouple protection tubes made from Alumina Ceramic are considered to have better mechanical strength (twice the tensile strength of Mullite) and better chemical resistance than Mullite protection tubes. They also have excellent abrasion resistance. Secondary metal tubes can be added for additional protection from mechanical damage. Since Alumina protection tubes are considered to be gas tight, they make excellent primary protection tubes. All tubes, which are used in horizontal installations and at elevated temperatures, should be supported to prevent mechanical breakage. Alumina tubes can be used for primary and secondary protection tubes on Noble Metal (Platinum based) thermocouples. This material has a very low silica content so they will not contaminate Platinum thermocouple elements above (2200°F or 1200°C) as a Mullite protection tube.