The molybdenum spot welding head is composed of two pieces of conductive metal bonded together. The centers of the two pieces of metal are insulated. As long as there is a contact at the tip, this contact constitutes a small resistance. The bottom of the welding head is flat and lubricated. When operating the machine, when the molybdenum spot welding head is pressed on the enameled wire by pneumatic means or with a foot pedal, the pressure will continue to increase. When the reaction force of the enameled wire on the welding head reaches the set welding pressure, it will Trigger a pulse current, the current time is very short, generally between a few milliseconds to ten milliseconds, about tens to more than one hundred amperes, the current flows from the bottom of the welding head, and there is a contact resistance at the tip of the welding head. The contact resistance will generate heat and sparks, this heat can remove the varnish of the enameled wire and a large amount of the heat will be transferred to the copper wire inside the enameled wire superior, a part of the current will from the bottom end of the welding head through the burned-out copper wire, the copper wire itself also heating, the copper wire in a short period of time before the temperature reaches the melting point of the melting state, under the action of pressure and metal underneath to from a new nugget, so that the enameled wire is connected with the metal.
2024