The tungsten rhenium thermocouple was first developed by Goedeke in 1931 and was the most successful refractory metal thermocouple developed in the 1960s and 1970s. The characteristics of tungsten rhenium thermocouple are: high melting point of the thermocouple wire (3300 ℃), low vapor pressure, and easy oxidation; Good chemical stability in non oxidizing atmosphere. High electromotive force and sensitivity, mainly due to its affordable price.
1. Classification of tungsten rhenium thermocouples. There are two types of tungsten rhenium thermocouples included in China's national standards:
A、 Tungsten rhenium 5-tungsten rhenium 26 has a nominal positive electrode composition of 95% tungsten and 5% rhenium, and a nominal negative electrode composition of 74% tungsten and 26% rhenium. The division number is WRe5-WRe26, abbreviated as W-Re5/26.
B、 Tungsten rhenium 3-tungsten rhenium 25, its positive electrode nominal composition is 97% tungsten and 3% rhenium, and the negative electrode nominal composition is 75% tungsten and 25% rhenium. The division number is WRe3-WRe25, abbreviated as W-Re3/25.
2. The use of tungsten rhenium thermocouples. At present, non-contact methods are commonly used to measure temperatures above 1600 ℃. However, this method has significant errors, and using contact methods can accurately measure the true temperature. In high-temperature thermocouples, precious metal thermocouples are expensive and can only reach a maximum temperature below 1800 ℃, while tungsten rhenium thermocouples not only have a high temperature limit but also good stability. Therefore, tungsten rhenium thermocouples are widely used in metallurgy, building materials, aerospace, aviation, and nuclear energy industries. China has abundant tungsten resources, and tungsten rhenium thermocouples are cheap and can partially replace precious metal thermocouples. They are a promising temperature measurement material in the field of high-temperature testing.
3. Use temperature. Its maximum operating temperature can reach 2800 ℃, but data dispersion occurs above 2300 ℃. Therefore, it is best to use at a temperature of around 2000 ℃.
4. Use environmental atmosphere. Tungsten rhenium thermoelectric dipoles are prone to oxidation and are suitable for use in inert or dry hydrogen gas, or with dense protective tubes to isolate them from oxygen before use. Cannot be used in a carbon containing atmosphere (such as in an atmosphere containing hydrocarbons, where corrosion occurs at temperatures exceeding 1000 ℃). Tungsten or tungsten rhenium is prone to generate stable carbides in a carbon containing atmosphere, which can reduce its sensitivity and cause brittle fracture. In the presence of hydrogen gas, it can accelerate carbonization.
5. Tungsten rhenium thermocouple is resistant to oxidation. This issue has always been a topic of concern for scholars both domestically and internationally, and they are committed to researching and solving it. Our company has adopted advanced international manufacturing technology and successfully developed a prefabricated high-temperature and high-pressure W-Re thermocouple. The temperature measurement range of this product is 0-1800 ℃, and it is widely used in metallurgy, coking, chemical kilns, heat treatment, glass and other industries. It has the advantages of high accuracy, low price, stable performance, and is not limited by the working environment and atmosphere. It is an ideal product to replace platinum rhodium thermocouples. The W-Re thermocouple produced by our company has been widely used in units such as Zhuzhou Hard Alloy Factory, Zigong Hard Alloy Factory, and Shenyang Zhongke Instrument, and its performance has reached the level of similar foreign products. Its technical indicators are as follows:
1. Division number: W-Re3/25，W-Re5/26
2. Temperature measurement range: 0-1800 ℃
3. Temperature measurement accuracy:< ± 1% t；< ± 0.5% t
4. Time constant: ≥ 180 s
5. Insulation resistance:> 5MΩ
6. Specifications and dimensions: 30050075010001100 (mm)
Special note: Currently, the W-Re thermocouples produced by our company are divided into four categories,

1. The fine ceramic protective tube used in this type of thermocouple is not limited by the working environment and can be used for a long time in any atmosphere, with a temperature measurement range of 0-1800 ℃;

2. Pure molybdenum protective tube, suitable for long-term use in vacuum, reducing or inert gas protection environments, preferably at temperatures below 1800 ℃, with short-term use temperatures up to 2000 ℃;

3. Tungsten protective tube can work for a long time at 2100 ℃, but it is difficult to process, resulting in a very expensive price;

4. Inconel600 alloy casing. This type of thermocouple can only work for a long time in a vacuum, oxidizing, or inert gas protected environment, suitable for a temperature range of up to 1150 degrees. It has strong oxidizing properties at high temperatures, and hydrogen usually makes it brittle, making it extremely sensitive to sulfur corrosion

Please select the thermocouple that is suitable for you based on our parameters.
Ordering instructions:
1. Indicate the thermocouple model, graduation number, and operating temperature.
2. Diameter and length of thermocouple protection tube.
3. Fasteners and flange devices, provide dimensions.

4. Non standard products can be produced according to user requirements in addition to standard products