Thermocouple of gasifier and method of making thermocouple protection sleeve

Abstract

The invention relates to a gasification furnace thermocouple and a preparation method of a thermocouple protection sleeve. The gasification furnace thermocouple comprises a thermocouple and the thermocouple protection sleeve arranged outside the thermocouple in a sleeved mode. The thermocouple protection sleeve comprises a middle-layer non-metal protection tube, an inner-layer metal inner protection tube and an outer-layer metal outer protection tube. The non-metal protection tube is prepared by sintering submicron silicon carbide powder in a pressureless mode; the metal inner protection tube and the metal outer protection tube are respectively prepared through alloy smelting; bonding layers are respectively arranged between the non-metal protection tube and the metal outer protection tube and between the non-metal protection tube and the metal inner protection tube; and the outer surface of the metal outer protection tube is provided with a protection layer. According to the preparation method of the thermocouple protection sleeve, layered preparation is adopted to enable the non-metal protection tube to be externally protected by the metal outer protection tube and internally supported by the metal inner protection tube used as a frame. The gasification furnace thermocouple has the excellent properties of being resistant to high temperature, high pressure, high-temperature slag corrosion and high-temperature slag erosion, is resistant both to oxidizing gases and reducing gases and is longer in service life.

Description

technical field [0001] The invention relates to a thermocouple, in particular to a gasification furnace thermocouple resistant to high-temperature redox, ash scouring and slag corrosion and a method for making the thermocouple protection sleeve. Background technique [0002] In the process of petroleum, chemical and other industrial production, especially in the period of rapid development of coal-to-oil and coal-to-gas industries in the coal chemical industry, the application of gasifiers is becoming more and more extensive. The gasifier is also the key equipment for producing synthetic ammonia in large-scale chemical fertilizer projects, and the heavy oil cracking gasifier is also the key equipment for producing synthetic ammonia raw material gas from heavy oil. The working pressure of the heavy oil cracking gasifier is 2.5-8.5Mpa, and the working temperature is 1350℃-1500℃. The medium composition in the furnace contains high concentration of oxygen and high-pressure steam...

AI Technical Summary

Problems solved by technology

Precious metal thermocouples are important temperature measuring equipment for gasifiers. Due to the influence of the working environment, the current thermocouple protection sleeves are easily corroded and worn out in a short period of time to cause cracks or fractures. The service life is generally 15 days to 15 days. 3 months, no regular period, need to be replaced frequently, so the production cost is high

This problem has not been well resolved so far.

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