Structure of thermocouple
From the principle of thermocouple temperature measurement, in addition to the two thermoelectrode materials, the basic thermocouple must be made into a measuring end and a reference end at both ends of the thermal electrode according to requirements, commonly known as "hot end" and "cold end". This is the so-called "two ends".
According to the different uses of thermocouples, there are four types of hot end insulation type, multi-branch insulation type, shell type and outcrop type, and the cold end has two methods: sealed and unsealed.
A thermocouple is generally composed of five parts. Two thermal electrodes (or wire) are the central part of the thermocouple (the first part of the temperature measuring element). The other parts are opened around it. In order to accurately transmit the measured temperature signal, an insulating material must be used to ensure reliable insulation between the two parts of the two hot electrodes except the two ends and between them and the outside world (the second part of the insulating material); in order to maintain the insulating material and Coupling wire, extending the service life of thermocouples, generally also designed with maintenance sleeves (part three maintenance tube); in order to facilitate the installation and use of wiring, at the same time to adapt to various applications, generally also designed with the fourth part of the wiring installation and fifth Partially mounted fixtures. These are the so-called "Five Parts". According to different uses, the basic thermocouple (that is, the thermocouple core) that can measure the temperature, there is no maintenance tube and no fixtures are installed. The assembled thermocouple is mainly composed of a junction box, a maintenance tube, an insulating sleeve, a terminal, and a thermal electrode, and is equipped with various installation and fixing devices.