The role of the thermocouple vacuum connector

Thermocouples are the most common temperature measuring elements. They are widely used in industry due to their wide temperature measurement range, high temperature measurement accuracy, simple structure and low cost. However, how to accurately measure temperature in a vacuum chamber is a more difficult problem. Why do you say that?

Vacuum is a relatively special environment. The temperature distribution of the same thermal field in a vacuum and in the atmosphere will be very different. Since the gas in a vacuum is very thin, heat exchange is mainly completed through heat conduction and thermal radiation. Thermocouples are a contact temperature measurement method. The temperature probe needs to be well fixed to the object to be measured to ensure that the temperature probe can quickly and accurately respond to temperature changes.

The difficulty lies in how to ensure the flexible arrangement of the temperature probe and the airtightness of the vacuum chamber. We already know that thermocouples can be classified into many thermocouples with different graduation numbers based on the different positive and negative electrode materials. Then the corresponding thermocouple vacuum connector lead must also use matching materials, which is a difficulty; how to quickly connect the thermocouple wire to the connector, especially when there are many temperature probes in the vacuum chamber, how to arrange and wire? This is the second difficulty.