Thermocouple steel furnace hot blast stove in iron and steel industry is mainly used to provide hot air to the smelting process, the arch temperature measuring thermocouple long running in 1200 ~ 1250 ℃ high temperature, high temperature can reach 1280 ℃, and strong vibration in the process of air supply. Because each enterprise use different coal quality, production of gas cleanliness is different also, hot blast stove often exist in the process of burning sulfur, phosphorus compounds, such as required thermocouple protection tube can resistance to high temperature air flow scouring corrosion, wear particles and high temperature gas. Traditional thermocouple protection tube, such as jade, disilicide key and ordinary silicon carbide steel due to the porosity, the cause of the high temperature strength, high temperature brittleness can easily lead to protect casing brittle fracture, accidentally silk pollution, corrosion, short service life of thermocouple, no reliable operation cycle. Protect casing nickel-based superalloy in presence of phosphide gas when using high temperature corrosion failure time is about 20 a 30 hours. My company in the long-term practice of all kinds of hot blast stove dome temperature measurement, constantly sum up experience, new achievements in the field of applied materials, using special SiC or heat resistant alloy as external protecting tube, using corundum as protection tube, and the measuring end processing, this kind of special thermocouple is developed, in the user on hot blast stove dome to use more than half a year. Scope of application and use temperature under the condition of the gas contain phosphide, outer casing by the introduction of German technology to produce a new type of silicon carbide to protect casing, the product porosity approximate zero. Has high air tightness, excellent oxidation resistance, corrosion resistance ability; High hardness, excellent wear resistance; High strength, strength increases with temperature rise. Isolated from a variety of harmful gas high temperature of the casing corrosion and erosion, the long-term use of around 1420 ℃ condition. Under the condition of the gas does not contain phosphide, the outer casing of heat-resisting alloy steel matrix, and the use reached the international advanced surface treatment technology, forming a 0 in the surface of metal casing. 5 ~ 1. 2 mm thick metal ceramic coating material. Coating material has high hardness, Up to HV1450) , high density ( ≥99. 5%, low porosity ( Hot blast stove thermocouple is designed for the iron and steel industry development, it has a high temperature resistant, fight corrode, air scour resistance and long service life, etc. Suitable for blast furnace, the hot blast stove dome hot mouth or temperature measurement, in areas such as the hot air pipe can also be used for natural gas, coal, cement kiln temperature measurement, etc. 1, heat pipe thermocouple is no pressure equipment, closed combustion, no open flame, can be directly installed in the side use with hot air equipment, hot air temperature can be in 60 Set freely within the range of 270 ℃, hot air outlet temperature difference is not more than + / - 3 ℃, the circulating hot air drying tunnel ( Box) Within the error is within + / - 1 ℃. 2, heat pipe thermocouple using high temperature 20 g tube plate, hot air chamber lid can open, heat pipe by cone snap ring 2 asbestos climbing root set set in the tube plate fork hole, change all the heat pipe can be removed, easy to maintain, 8 - the service life of hot blast stove 15 years. 3, adopting removable plug-in explosion-proof high temperature fan structure of mechanical and electrical integration, fan panel screws, fan can overall unload driving part, shall not affect the outsourcing and whole, heat pipe air furnace adopt outsourcing caigang rock wool sandwich panel, overall the beauty is generous. 4, the use of advanced automatic control technology, with temperature display, overheating protection, a variety of protection of kinetic energy of wind protection and delay shutdown, safe and reliable operation. 5, preparation of hot air heat pipe hot air direct operation cost is the preparation of thermal electric heating air, steam boiler, and about 30% of the preparation of hot air, heat conduction oil boiler with the tube still hot air chamber 40 - Of 50%, at the same time to avoid the column tube furnace tube plate cracking flue gas mixing sequence of causing injury. 6, each heat pipe of heat pipe thermocouple components are independent, even if the individual heat pipe failure, will not lead to smoke - Air, little impact on the performance of the hot blast stove.