Before soldering the thermocouple measuring end, the tip of the soldered hot electrode should be twisted or twisted at the top.
(1) Gas welding method: first twist the top of the hot electrode into a twist shape, then slightly heat and pry the flux, then use the acetylene flame to melt the measuring end into a spherical shape, and then quickly remove the measuring end from the flame and then put it into the hot water. This method is simple to operate and therefore has a wide application.
(2) Arc welding method: Arc welding uses a high temperature arc to melt the measuring end of the thermocouple into a spherical shape. Commonly used are AC arc welding and DC arc welding. AC arc welding is commonly used to weld base metal thermocouples. Before soldering, solder the solder on the top of the hot electrode. After soldering, remove the solder from the solder joint. DC arc welding is commonly used to weld precious metal thermocouples.
(3) Butt welding: Align the tops of the hot electrodes, add some pressure, and then turn on the power to melt the contact surfaces together. This welding method is more convenient.
(4) DC argon arc welding: DC argon arc welding is an ideal method for welding thermocouples developed in recent years. Usually, the DC argon arc welding thermocouple welding machine is protected by argon gas, high frequency arc ignition, DC welding, and can be butt welded. It is composed of power supply, DC welding power source 1, welding torch 2, high frequency oscillator 3, butt welding power supply and fixture 4, etc. This welding device is characterized by convenient use, fast welding speed and no contamination. Without any air holes, the soldering end points are bright and beautiful, and can be used in one machine. It can weld a variety of metal materials and a variety of thermocouples of different specifications. Thermocouples choose Jack for thermocouples.
(5), salt bath welding method: the welding device consists of a pressure regulator (3-5kW), graphite crucible and welding clips. As the power source-electrode, the hot electrode is soldered as the other electrode. Before welding, the oxide of the surface of the hot electrode is cleaned and twisted into a twisted shape. The carbon rod is placed on the ruthenium chloride, the power is turned on to melt the ruthenium chloride, and the thermocouple hot electrode is chlorinated. The crucible melts slightly after contact with the arc to be removed, and the cerium chloride particles on the measuring end and the hot electrode are washed with hot water.
If you want to know more information, you can click this link.