Loading patent…
AssigneesNippon Steel Corporation, Asahi Glass Company, Limited
InventorsYoshiaki Shia, Hideaki Mori, Otojiro Kida, Hiroshi Taketsugu
Estimating the term…
A thermocouple temperature sensor employs a protecting tube made of metal-boride-based ceramics, and a platinum -rhodium-based thermocouple. To prevent a deterioration of the thermocouple due to a reducing gas generated in the protecting when used at a high service temperature, the thermocouple is placed in an insulation tube, which is placed inside the protecting tube. In addition, a front end portion of the insulation tube is covered with a noble-metal cap mainly composed of platinum group metal, to prevent the reducing gas generated in the protecting tube from reaching a connection point of the thermocouple. The top end of the protecting tube is open, and a terminal box with a ventilation means to smoothly discharge the reducing gas in provided. This arrangement remarkably prolongs the service life of the thermocouple, and thus it is able to continuously measure the temperature of molten pig iron and molten steel for a long interval.
A thermocouple temperature sensor comprising a platinum-rhodium-based thermocouple having first and second metal wires, a connection point of the wires forming a heat sensing portion;
A method of measuring the temperature of molten iron by immersing a front end portion of a thermocouple temperature sensor into the molten iron, the thermocouple temperature sensor involving a platinum-rhodium-based thermocouple having first and second metal wires, a connection point of the metal wires forming a heat sensing portion, an oxide insulation tube accommodating the metal wires, the heat sensing portion of the thermocouple being exposed from a front end portion of the insulation tube, a noble-metal cap mainly composed of platinum group metal completely covering the front end portion of the insulation tube to thereby cover the heat sensing portion of the thermocouple, an inner protecting tube mainly composed of platinum group metal completely covering the front end portion of the insulation tube to thereby cover the heat sensing portion of the thermocouple, an inner protecting tube mainly composed of alumina accommodating the insulation tube and the noble-metal cap, and a protecting tube made of metal-boride-based ceramics accommodating the inner protecting tube.
Dependencies are inferred from the claim text.