HI Temp Solutions

This leaflet shows several designs of Thermocouples which can be used under very different field conditions, for example - for temperature measurement in Nuclear Energy Plants, Reactor or Compressor Vessels in the Chemical Industry, Heat Treatment Furnaces, Gas Turbines, Power Stations, Boiler Flue gases, Skin Surface, Super Heaters and for many varied applications in Laboratories.

These Thermocouples are flexible, can be manufactured in small dimensions and have a quick response time.

The outer sheath, the Thermocouple wires, and the Insulation material form an inseparable unit, the Thermocouple wires being insulated from each other and from the sheath with high purity mineral oxide.

DetrivMineral Insulated Thermocouples are available in 4 different standards outside diameters with either Iron-Constantan Nickel-Chromium/Nickel or Cu-Constantan Wires according to DIN or ASA standards. The sheath is either of Stainless Steel or Heat Resistant Alloy Inconel 600. Depending upon the Thermocouple wire and sheath material, these Thermocouples can be used for temperatures of over 1000C. Lengths of 40 meters and more can be supplied.

The simplest thermocouple is made using a bare wire configuration that is two thermo elements joined at one end and directly exposed to the atmosphere of the operating environment. The operating environment can be an oxidizing, reducing or inert atmosphere and constrains on the use of thermo elements in some atmospheres can exist because of lack of compatibility between the materials the thermo elements are made of and the gases. For instance W/W-Re thermocouples cannot be used in oxidizing atmosphere because, above 600°C, tungsten reacts easily with oxygen producing volatile oxides: the thermo elements can be rapidly damaged and fail.

The MIMS (Mineral Insulated Metal Sheathed) configuration can overcome the problems arising from the interaction between thermo elements and atmosphere: the thermo elements are protected from the environment using a metallic sheath; between the thermo elements and the sheath a ceramic material provides electrical insulation.