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, high sensitivity, mainly due to its affordable price.

At present, non-contact methods are commonly used to measure temperatures above 1600 ℃. However, this method has a large error, and using the contact method can accurately measure the true temperature. In high-temperature thermocouples, precious metal thermocouples are expensive and can only reach temperatures below 1800 ℃. However, tungsten rhenium thermocouples not only have a high temperature measurement limit, but also have good stability. Therefore, tungsten rhenium thermocouples are widely used in industries such as metallurgy, building materials, aerospace, aviation, and nuclear energy. China has abundant tungsten resources, and tungsten rhenium thermocouples are cheap and can partially replace precious metal thermocouples (platinum rhodium thermocouples). They are a promising temperature measurement material in the field of high temperature testing. Its high operating temperature can reach 2800 ℃, but data dispersion occurs above 2300 ℃. Therefore, it is recommended to use a temperature of around 2000 ℃.

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.

The issue of oxidation resistance of tungsten rhenium thermocouples has always been a topic of concern for scholars at home and abroad, and efforts have been made to study and solve it. Prefabricated high-temperature and high-pressure tungsten rhenium thermocouple, with a temperature measurement range of 0-1800 ℃, 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 tungsten rhenium thermocouple produced by our company has been widely used in many units, and its performance has reached the level of 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:>5M Ω

6. Specifications and dimensions: 30050075010001100 (mm)

The tungsten rhenium molten steel rapid temperature measurement thermocouple is designed and manufactured specifically for measuring the temperature of molten steel, molten iron, and other metal melts. It has the advantages of small size, fast thermal response speed, high accuracy, and low price. Its technical indicators are as follows:

1. Z.ui high temperature measurement temperature: 1800 ℃

2. Temperature measurement accuracy: ≤ 0.5%

3. Insulation resistance: ≥ 30 M Ω

4. Measurement rate: ≥ 98%

5. Response time:<5 seconds

At present, the tungsten rhenium thermocouples produced by our company are divided into three categories:

One type is the use of fine ceramic protective tubes The specifications of ceramic tubes include: diameter of Ø 8, Ø 10, Ø 12, Ø 14, Ø 16, length of 300-1100mm. These thermocouples are not limited by the working environment and can be used in any atmosphere for a long time. The temperature measurement range is 0-1800 ℃

The other type is pure molybdenum protective tube The specifications of molybdenum and tungsten tubes include: diameter of Ø 6, Ø 8, Ø 10mm, length of 500~700mm. This type of thermocouple can only work for a long time in a vacuum, reducing or inert gas protection environment. Molybdenum tubes should be used for a long time at temperatures below 1800 ℃, and short-term use temperatures can reach 2000 ℃;

Another type is tungsten protective tube As for tungsten tubes, they can work for a long time at 2100 ℃, but they are difficult to process, making them very expensive.