The characteristics of tungsten-rhenium thermocouple are: hot electrode wire melting point is high (3300℃), steam pressure, easy oxidation; Good chemical stability in non - oxidizing atmosphere. High electromotive force, high sensitivity, and mainly cheap.

At present, non-contact method is often used to measure the temperature above 1600℃. However, the error of this method is large. For example, the contact rule can accurately measure the real temperature. In high temperature thermocouple, precious metal thermocouple is expensive and z.u high temperature can only be below 1800℃, and tungsten-rhenium thermocouple not only high temperature, and good stability, therefore, tungsten-rhenium thermocouple in metallurgy, building materials, aerospace, aviation and nuclear energy and other industries are widely used. Our country's tungsten resource is rich, the price of tungsten rhenium thermocouple is cheap, and can partially replace the precious metal thermocouple (platinum-rhodium thermocouple), it is the promising temperature measurement material in the high temperature test field. Its z.u high use temperature can reach 2800℃, however, above 2300℃, data dispersion. Therefore, the use of temperature z.u is good about 2000℃.

Tungsten-rhenium thermocouples are easily oxidized and are suitable for use in inert or dry hydrogen, or with dense protective tubes to isolate it from oxygen. Can not be used in the atmosphere containing carbon (such as in the atmosphere containing hydrocarbons, the temperature above 1000℃ will be corroded). Tungsten or tungsten-rhenium tends to form stable carbides in carbon-containing atmospheres, which reduces its sensitivity and causes brittle breakage, and accelerates carbonization in the presence of hydrogen.

The problem of tungsten-rhenium thermocouple oxidation resistance has always been concerned by scholars at home and abroad, and is committed to research and solution. Prefabricated high temperature and high pressure tungsten-rhenium thermocouple, the product temperature range is 0 ~ 1800℃, widely used in metallurgy, coking, chemical kiln, heat treatment, glass and other industries, it has high precision, low price, stable performance, not limited by the working environment atmosphere and other advantages, is an ideal product to replace platinum rhodium thermocouple. Our company's production of tungsten rhenium thermocouple has been widely used in many units, its performance has reached the level of similar foreign products. Its technical indicators are as follows:

1. Indexing 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: 300,500,750,1000,1100 (mm)

Tungsten-rhenium rapid temperature measuring thermocouple in molten steel is designed and manufactured for measuring the temperature of molten steel, liquid iron and other metal melts. It has the advantages of small volume, fast thermal response, high accuracy and low price. Its technical indicators are as follows:

1, z.u high temperature measurement temperature: 1800℃

2, temperature measurement accuracy :≤ 0.5%

3, insulation resistance :≥30 MΩ

4, measurement rate :≥98%

5. Reaction time: < 5 s

At present, the tungsten-rhenium thermocouple produced by our company is divided into three categories:

One is the use of fine ceramic protective tube. The specifications of the ceramic tube are: diameter of 8, 10, 12, 14, 16, length of 300~1100mm, this kind of thermocouple is not limited by the working environment atmosphere can be used in any atmosphere for a long time, the temperature range is 0~1800℃

The other type is pure molybdenum protective tube. Molybdenum tube and tungsten tube specifications: diameter of 6, 8, with a diameter of 10mm, length of 500~700mm, this thermocouple can only work in vacuum, reduction or inert gas protection environment for a long time, molybdenum tube z.u is best in the temperature below 1800℃ long-term use, short-term use temperature can reach 2000℃;

And then there's the tungsten tube. As for the tungsten tube, it can work at 2100℃ for a long time, but it is difficult to process, making it very expensive.