Measurement of high temperatures, higher than 1000 C, using ceramic based thermocouples is a well known process. To do this successfully the resistance wires inside the thermocouple need to be insulated and protected.
Using Ceramic materials to guard the platinum based wire is a method which has been used for quite some time, due to the exceptional heat resistant properties of these materials. The thermocouple is the most popular heat measurement implement which is utilized for measuring the temperature inside of a furnace, typically used to the melting or heat treatment of metal or indeed for manufacturing ceramic products.
The ceramic components within a typical thermocouple device are definitely the outer protection tube that is certainly in contact with the furnace. Occasionally multiple tubes are used inside the other person to supply the quantity of insulation and protection required.
Ceramic insulators (Tubes with 2 or maybe more core holes through them) may also be employed to isolate the two or more wires that go to the bi-metallic joint on the head the point through which sens0rs temperature is measured.
The standard materials used for that tube can be a 99.7% alumina material, impervious tube, which can be attached typically into a metal thermacouple head, containing a terminal block which is used to get in touch to your standard wire for the instrumentation. In the less demanding heat atmosphere a mullite tube may be used being a cheaper alternative, which can work sufficiently around 1600 ‘oc. The mullite tube is likewise an impervious tube and it has 60% alumina content.