Temperature Sensors up to 3000 °C

Type K sheathed thermocouples for use between 0 and 1,100 °C, sheath material Inconel, compensation cable firmly connected and cast 4 m, operating in a vacuum, nitrogen, argon, air and hydrogen

Type K sheathed thermocouples for use between 0 and 1,200 °C, sheath material Inconel, compensation cable firmly connected and cast 4 m, operating in a vacuum, nitrogen, argon, air and hydrogen

Type N sheathed thermocouples for use between 0 and 1,200 °C, sheath material Inconel, compensation cable firmly connected and cast 4 m, operating in a vacuum, nitrogen, argon, air and hydrogen

Type S thermocouple with one-sided closed ceramic protective tube for use in between 0 and 1,600 °C, non-flexible, protective tube tight ceramic 99.7, thermocouple connection head with 3 m compensation cable, operation in air, nitrogen and argon

Type B thermocouple with one-sided closed ceramic protective tube for use in between 0 and 1,800 °C, non-flexible, protective tube tight ceramic 99.7, thermocouple connection head with 3 m compensation cable, operation in air, nitrogen and argon

Type C sheathed thermocouples for use between 0 and 2,200 °C, sheath material molybdenum, compensation cable firmly connected and cast 3 m, non-flexible, operation in a vacuum, nitrogen, argon and hydrogen

High temperatures are generally regulated using pyrometers. These pyrometers have a pre-defined measuring range. We employ pyrometers with a standard 350-2500 °C.

When the process starts the furnace is at room temperature and must be initially heated undefined in the pyrometer measuring range. With sensitive batches this is unacceptable and the temperature must be increased from room ambient temperature in a regulated manner. To do this a so-called sliding thermocouple is installed in the high temperature furnaces. The thermocouple runs automatically after charging in the furnace and registers the current temperature during heating up. In the case of an ad- justable switching temperature the pyrometer carries out the regulation and the thermo sensor leaves the hot zone because it would not withstand the follow- ing high temperatures without sustaining damage. During cooling the thermocouple returns automati- cally into the furnace and regulates the automatic processes at low temperatures.

Pyrometers are visual radiation measuring devices. In a vacuum furnace the pyrometers must measure through a vacuum-tight disc. This disc can become dirty and thus influence the recorded measurement. To check the regulating pyrometer a second refer- ence pyrometer can be supplied as a group. The win- dow of this pyrometer is protected against soling by a valve. The valve opens, e.g. every 30 minutes for 30 seconds. The recorded result can be documented in the data recording system. If the measuring result in the reference pyrometer suddenly jumps, the disc of the regulating pyrometer is probably soiled and must be cleaned before the next run.