Thermocouple is a vulnerable device in resistance furnace. Reasonable selection and use can prolong its service life and save money.
Thermocouple is an important device in resistance furnace. It is necessary to measure the real-time temperature in the furnace in any experiment. Thermocouple has become the most widely used temperature sensing element in industrial production and scientific research because of its stable performance, accurate and reliable, simple structure, easy to use, wide range of temperature measurement, and remote signal transmission. But frequent use will also make its life loss faster. Reasonable selection of different materials of thermocouples and the increase of thermocouple protection tube is a very effective means.
The thermocouple protection tube has two main uses: one is to prevent mechanical damage; the other is to protect the thermocouple from chemical corrosion of the measured medium and from the harmful influence of oxidation or reduction atmosphere, so as to make the thermocouple as close to its best atmosphere as possible. Therefore, the thermocouple must be protected from bad atmosphere.
Thermocouple is the most widely used temperature sensor. The long-term stability, service life and other performance indicators of thermocouple are closely related to the protection tube. The damage rate of thermocouple directly depends on the performance of protective tube material.
Performance and selection
The protective tube can be divided into three types according to their materials:
1. Metal: high mechanical strength, good thermal conductivity, widely used.
2. Non metallic: mostly used in temperature measurement above 1000 ℃, good heat resistance, poor shock resistance and thermal conductivity.
3. Cermet: due to the high mechanical strength of metal materials, but not high temperature resistance; non-metallic materials high temperature resistance, but low mechanical strength. The cermet protective tube made by powder metallurgy has high temperature resistance and good mechanical strength. It has a good application prospect and can be widely used in the harsh environment of molten steel, hot metal and high temperature salt bath furnace.
It can be seen that the thermocouple in normal use mainly depends on the life of the protection tube, and its material selection determines the length of its life. Different materials can be selected according to the needs of the enterprise to ensure the normal production and measurement.
The thermocouples selected by our company are all domestic famous brand products, and the zirconium diboride thermocouple developed by our company has a measuring temperature of 2600 ℃. Such a high temperature requires the protection of thermocouple in the process of using resistance furnace.
On 2018-08-08 11:45:46
