Thermocouple protection tube is mainly used to protect the metal wire inside the thermocouple, such as the ceramic thermocouple tubes and metal thermocouple tubes, to ensure the metal wire is not damaged by the environment.
The silicon nitride thermocouple protection tube, also called syalon tube, or sialon tube, maily used in the aluminun fountry or casiting, is characterized by non-infiltration with molten metal, high temperature resistance, corrosion resistance, oxidation resistance, and non-pollution.
In order to extend the service life of the thermocouple, please pay attention to as following mention.
1, Silicon nitride tube is a ceramic material fragile. In the transportation, installation, and dismantling, special attention should be paid to the thermocouple protection tube and can not be subjected to strong impact, so in the installation of the use of as light as possible to hold and to put.
2, Silicon nitride ceramic protection tube and metal material contact should be installed with temperature-resistant rubber pads or adhesive bonding, etc., to prevent damage to the silicon nitride protection tube.
3, Installed thermocouple whole piece of hot load, preheat to 300-500 ℃ before use, or cold loaded with the furnace with the slow warming, to achieve the purpose of extending the life.
4, Silicon nitride ceramic protection tube in the oxygen conditions of the maximum operating temperature ≤ 1400 ℃, to prevent oxidation affects its service life. Under vacuum or protective atmosphere, the maximum operating temperature is ≤1800℃.
5, Silicon nitride ceramic protection tube should be stored in a dry environment to prevent water on the silicon nitride ceramic performance.
6, Regular cleaning of surface aluminum oxide on the silicon nitride thermocouple protection tube. During the cleaning process, you need to use a well heated tool, do not use cool tools.
7, Remove the impurities attached to the surface of the silicon nitride thermocouple protection casing, it is best to protect the casing in a high temperature state.
