Projection welding

Projection welding corresponds in principle to spot welding, whereby one or more elevations (welding projections), are introduced into one of the components, to be connected. These projections then rest on the welded parts. Planar copper electrodes will be used, as compared to spot welding.

During the current flow, the projection partially fuses, pushes the material of the projection in another component and forms a connection with this. Another variation of projection welding is the use of natural projection, for example, for the welding of grids (so-called cross-wire welding). Thereby, current flows through the contact points of the mutually intersecting metal rods, with heating and welding occurring at these locations.

Advantages

The advantages of projection welding are related to the reduced electrode wear and to the simultaneous welding of several projections. Given the division of the welding current, between several projections, the welding current source must be able to supply a higher current, corresponding to the number of projections.

The high currents required for projection welding represent a specialty of Harms & Wende. The several hundred kA of current, using inverter technology, represent technical pioneering achievements of the Harms & Wende development. This also applies to the monitoring of projection welding, through specially-developed monitoring functions.

Error patterns for projection welding – safely detected with PQS