What are the welding methods at the end of the thermocouple?
Toner toner welding type K thermocouple welding device similar to arc welding, the difference is not connected with one pole of a power supply is connected, but Sheng graphite crucible carbon, the other pole connected by welding thermocouple. When welding, insert the thermoelectric pole into the graphite powder and weld it in a few seconds. This welding method is more convenient than arc welding, but it is easy to cause thermoelectric brittle fracture. This method is suitable for welding low metal thermocouples.
Salt welding type K thermocouple in the beaker into the sodium chloride solution into the platinum wire in aqueous solution as an electrode, and the electrode heat as another electrode. When soldering, contact the top of the thermocouple with the solution slightly, switch on the power supply and switch off the power quickly after the arc is started. This welding method is suitable for welding 0.03mm-0.3mm thermocouples with finer welding diameter.
Welding type K thermocouple using gas welding, should be very heated and dipped in the top heat flux (such as nickel chromium nickel silicon thermocouple flux is four boric acid and sodium sand half mixture), then placed thermode acetylene or hydrogen flame, to melt into a ball out rapidly after, immediately placed in hot water wash the residue on the welding point. This method is easy to operate and widely used. Welding for low metal thermocouples.
Argon arc welding type K thermocouple argon arc welding equipment consists of 5 parts, such as DC welding power supply, high frequency oscillator, welding gun, welding power supply and clamp. When welding, the cerium tungsten wire extending out of the welding nozzle is used as the negative electrode, and the welding thermocouple is fixed on the fixture as an anode. When the poles by high frequency and high voltage when the arc ignition function, using thyristor voltage control, arc intensity, under the protection of argon to cerium tungsten and generating arc discharge between welding thermocouple, high temperature generated by the arc melting end of the thermocouple wire into a ball. In order to facilitate the alignment of the thermocouple with the electrode, the work fixture and the welding torch can move in both horizontal and vertical directions. The welding torch is equipped with cerium tungsten electrode of diameter 1mm and 1.5mm, which is used for welding thermocouples of different diameters.
