Mineral insulated thermocouple cable consists of an outer metal sheath that houses the thermocouple conductors; the sheath is then filled with a highly compacted magnesium oxide powder to prevent the conductors contacting at any point other than the fixed junction. This construction allows the sheaths to be easily bent or formed to shape as required by the user, but remain rigid during use. The whole assembly is hermetically sealed giving the conductors full protection from the operating environment.
Mineral Insulated thermocouples have a wide temperature range are robust, flexible and can be made in long lengths and with a broad range of diameters. They also have a very fast response time, and generally more resistant to chemicals due to the sheath and insulating power protecting them meaning they have a longer life than normal sensors.