Resistance Projection Welding
Resistance projection welding is a welding process where the current flow is concentrated through pre-formed projections on one joint partner. This allows simultaneous welding of multiple points.
Physical-Chemical Mechanism of Action
The current flow through the weld projections creates local hot spots that melt the metal near the projection. The molten materials are then pressed together and form a solid joint.
Metallurgical Relevance & Risks in Welding
The localization of current flow can lead to uneven heat distribution, causing stresses and potential cracks in the material. Incorrect projection positioning can result in insufficient welding in certain areas.
Workshop Practice & Instructions
Ensure that the projections are correctly positioned and the current flow is evenly distributed. The heating time should be set so that the material is sufficiently welded without building up too much stress. A typical heating time is 1 to 2 seconds per projection.