By Goedecke tungsten-rhenium thermocouples is 1931 grams (Howard) first developed, developed in the 60 s to 70 s most successful refractory metal thermocouple. Tungsten-rhenium thermocouples features are: hot wire electrode high melting point (3300 ℃), steam down, extremely easy oxidation; In the oxidizing atmosphere chemistry stability is good. Electromotive force is big, high sensitivity, the most main or cheap.
1, the classification of tungsten-rhenium thermocouples. Included in the national standard of tungsten-rhenium thermocouples in China has two kinds:
26 A, 5 - rhenium tungsten rhenium tungsten, it is the name of the anode components in containing 95% 95%, rhenium, tungsten cathode nominal composition of containing 74%, 26% rhenium tungsten. Index number of WRe5 - WRe26, abbreviated: W - Re5/26.
B, tungsten rhenium 3 - tungsten rhenium 25, it the name of the anode components in containing 97% 97%, rhenium, tungsten cathode nominal composition of containing 75%, 25% rhenium tungsten. Index number of WRe3 - WRe25, abbreviated: W - Re3/25.
2, the use of tungsten-rhenium thermocouples. At present, a lot of measuring temperature above 1600 ℃, the non-contact method is adopted, however, the method of error is bigger, such as contact law can accurately measure the true temperature. In high temperature thermocouple, thermocouple is expensive and precious metals can only the highest temperature under 1800 ℃, and tungsten rhenium thermocouple temperature measurement not only high ceiling, and good stability, therefore, tungsten-rhenium thermocouples in metallurgy, building materials, aerospace, aviation, and nuclear power and other industries are widely used. Tungsten resources in our country, the tungsten-rhenium thermocouples cheap, can partially replace precious metal thermocouple, it is very promising in the area of high temperature test of temperature measuring materials.
3, the use of temperature. Its highest temperature can reach 2800 ℃, but, when higher than 2300 ℃, scattered data. Therefore, the use of temperature at 2000 ℃ or so best.
4, using the environment atmosphere. Tungsten-rhenium thermocouples are easily oxidized, suitable for use in dry inert or hydrogen, or with dense protection tube separate it with oxygen. Cannot be used for carbon atmosphere, such as used in the atmosphere containing hydrocarbons, a temperature over 1000 ℃ or corrosion). Tungsten or tungsten rhenium easy to generate stable carbides in carbon atmosphere, so that to reduce its sensitivity and cause the brittle fracture, the presence of hydrogen, will accelerate carbonization.
5, tungsten-rhenium thermocouples antioxidant. The problem of scholars at home and abroad has been a topic of concern, and dedicated to the study. Our company adopted the international advanced fabrication process, successfully developed the prefabricated high temperature and high pressure W - Re thermocouple, the temperature of the product range of 0 ~ 1800 ℃, it is widely used in metallurgy, coking, chemical furnace, heat treatment, glass and other industries, it has high precision, low price, stable performance, without being limited by the working environment atmosphere, etc, is an ideal product to replace platinum rhodium thermocouple. My company production of W - Re thermocouple has been in zhuzhou cemented carbide factory, zigong cemented carbide factory and shenyang zhongke instrument etc, are widely used, its performance reached the level of similar products abroad. The technical indicators are as follows:
1, dividing number: W - Re3/25, W - Re5/26
2, temperature measuring range: 0 ~ 1800 ℃
3, temperature measurement precision: < t plus or minus 1%; "Plus or minus 0.5% t
4, time constant: 180 s or higher
5, insulation resistance: > 5 m Ω
6, size: 300500750100, 0110 (mm)
Rhenium tungsten steel rapid temperature measuring thermocouple is designed for measuring liquid steel, iron and other metal melt temperature and the design and manufacture, it has some volume response speed, high accuracy, and low price. The technical indicators are as follows:
1, the highest temperature measuring temperature: 1800 ℃
2, temperature measurement accuracy: 0.5% or less of t
3, insulation resistance: Ω 30 M or higher
4, measure into rate: 98% or higher
5, the reaction time: < 5 s
Special note: at present our company produces the W - Re thermocouple points three kinds, one kind is the fine ceramic protection tube, another kind is pure molybdenum protection tube, is kind of tungsten protection tube. Of the specifications of the ceramic tube are: Ф diameter 8, 10, Ф Ф 12, 14, Ф Ф 16, 300 ~ 1100 mm in length, this kind of thermocouple can not be restricted by working environment atmosphere in any atmosphere medium and long-term use, temperature range is 0 ~ 1800 ℃. Molybdenum and tungsten tube specifications are: Ф diameter 6, 8, Ф Ф 10 mm, 500 ~ 700 mm in length, the thermocouple in a vacuum, reduction or inert gas protection of the environment medium and long term work, molybdenum tube is the best long-term use under the temperature under 1800 ℃, short-term use temperature to 2000 ℃; As for the tungsten tube can long-term work under 2100 ℃, but it is hard to processing and its price is very expensive. Please choose according to our parameters suitable for your thermocouple.
