1. Spot welding
Solder mask machine
Spot welding is a resistance welding method in which the weldment is assembled into a lap joint and pressed between two cylindrical electrodes, and the base metal is melted by resistance heat to form a welding point. Spot welding is mainly used for thin plate welding. The process of spot welding:
1. Pre-press to ensure good contact between workpieces.
2. Power on to form a nugget and a plastic ring at the weld.
3. Power-off forging, so that the nugget is cooled and crystallized under the continuous action of pressure, forming a densely organized, no shrinkage, crack-free solder joint.
2. Seam welding
The process of seam welding is similar to spot welding, except that the cylindrical electrode is replaced by a rotating disc-shaped roller electrode, and the weldment is assembled into a lap or butt joint and placed between the two roller electrodes. The roller presses the weldment and rotates. Continuous or intermittent power transmission to form a continuous welding seam resistance welding method.
Seam welding is mainly used for welding structures with relatively regular welds and requiring sealing, and the plate thickness is generally below 3mm.
3. Butt welding
Butt welding is a resistance welding method that welds the weldment along the entire contact surface.
Fourth, projection welding
Projection welding is a process of pre-processing one or more protruding points on the bonding surface of a workpiece, making it contact with the surface of another workpiece and heating it with electricity, and then pressing down to make these contact points form solder joints. Resistance welding method. Projection welding is a variant of spot welding and is mainly used for welding stampings of mild steel and low alloy steel. The most suitable thickness of plate projection welding is 0.5~4mm, and spot welding should be used when it is less than 0.25mm. With the development of the automobile industry, high-productivity projection welding has been widely used in the manufacture of auto parts. Projection welding is also widely used in wire, pipe and other connections.
