Tungsten rhenium thermocouple is 1931 by the Goedecke (Ge DS g) first developed, the most successful of refractory metal thermocouples 60-70 years to develop a tungsten-rhenium thermocouples features are: high melting point hot wire ( 3300 ℃), low vapor pressure, easily oxidized; in a non-oxidizing atmosphere EMF good chemical stability, high sensitivity, the most important is cheap.
. 1, tungsten-rhenium thermocouples included in the national standard classification of tungsten rhenium thermocouples in two ways:
A, tungsten, rhenium, tungsten, rhenium 5- 26, its positive nominal composition containing tungsten 95% rhenium 5%, negative nominal composition containing tungsten 74% rhenium 26% sub-degree No. WRe5-WRe26, shorthand: W-Re5 / 26.
B, tungsten, rhenium, tungsten, rhenium 3- 25, its positive nominal composition containing tungsten 97% rhenium 3%, negative nominal composition containing tungsten 75% rhenium 25% sub-degree No. WRe3-WRe25, shorthand: W-Re3 / 25.
2, tungsten-rhenium thermocouples used currently measured temperatures above 1600 ℃, the use of non-contact method, however, the error of the method is large, such as a contact rule can accurately measure the real temperature in the high temperature thermoelectric Even in the most expensive and precious metal thermocouple temperature only below 1800 ℃, and tungsten-rhenium thermocouple temperature upper limit is not only high, but also good stability, therefore, tungsten-rhenium thermocouples in metallurgy, building materials, aerospace, aviation and nuclear energy and other industries have been widely used rich resources of tungsten, tungsten-rhenium thermocouples cheap price, you can partially replace the precious metal thermocouples, it is in the field of high-temperature test promising temperature materials.
3, use temperature of the highest temperature it can reach 2800 ℃, however, when higher than 2300 ℃, the data dispersion. Therefore, the temperature is preferably about 2000 ℃.
4, using the atmosphere. Tungsten-rhenium thermocouples easily oxidized, suitable for use in an inert or dry hydrogen, or with a dense protective tube and oxygen cut off in order to use it. Not be used for carbon-containing atmosphere (eg containing use hydrocarbon atmosphere, temperatures in excess of 1000 ℃ that is subject to corrosion). tungsten or tungsten rhenium easy atmosphere in the carbon to form stable carbides, resulting in lower sensitivity and cause brittle fracture, the presence of hydrogen in the case, It will accelerate the carbonation.
5, tungsten-rhenium thermocouples antioxidant. The issue has been the subject of concern by scholars at home and abroad, and is committed to study and solve. I am using the international advanced making technology, successfully developed a high temperature and high pressure fabricated W-Re thermocouples, temperature range of the product is 0 ~ 1800 ℃, widely used in metallurgy, coking, chemical furnace, heat treatment, glass and other industries, it has a high precision, low price and stable performance, the atmosphere is not limited by the working environment etc., is the ideal product instead of platinum and rhodium thermocouple. I produced the W-Re thermocouple in Zhuzhou Cemented Carbide factory has Zigong Cemented Carbide factory and Shenyang Branch of the instrument, and other units, widely used, its performance has reached abroad . similar products of its technical indicators are as follows:
1, index number: W-Re3 / 25, W-Re5 / 26
2, temperature range: 0 ~ 1800 ℃
3, temperature measurement accuracy: (± 1% t; (± 0.5% t
4, time constant: ≥180 s
5, insulation resistance:) 5MΩ
6, Size: 30050075010001100 (mm)
Steel tungsten-rhenium thermocouple is designed for rapid measurement of molten steel, iron and other metals melt temperature was designed and manufactured, and it has some volume, fast response, high accuracy, low price of its technical indicators are as follows:
1, the maximum temperature temperature: 1800 ℃
2, temperature measurement accuracy: ≤ 0.5% t
3, Insulation resistance: ≥30 MΩ
4, measuring success rate: ≥98%
5, reaction time: (5 s
Special Note: Currently, I produced the W-Re thermocouple divided into three categories, one is the use of fine ceramic protective tube, and the other is pure molybdenum protective tube, and then a class that is tungsten protective tube ceramic tube specifications: diameter Ф8, Ф10, Ф12, Ф14, Ф16, length 300 ~ 1100mm, this type of thermocouple working atmosphere without limitation can be used in any climate and long-term, temperature range is 0 ~ 1800 ℃; the molybdenum and tungsten tube tube specifications: diameter Ф6, Ф8, Ф10mm, length 500 ~ 700mm, such thermocouples can only be in a vacuum, reducing or inert gas protection of the environment and long-term work, preferably at a temperature of molybdenum tube is 1800 ℃ below the long-term use, short-term use temperatures up to 2000 ℃; As long tungsten tube is able to work at 2100 ℃, but difficult to process so that its price is very expensive according to our preferences appropriate for your thermocouple.