1.Machined annular projections
Typically, an annular 'V' projection is machined in a solid component to achieve, just prior to welding, line contact with the component to which it is to be welded. In the early stages of welding, the projection concentrates force and current into a small contact area. Uniformity of projection shape and height is essential for achieving consistent weld quality.
60° included angle cone
Suitable where sheet is thick enough to support electrode force and prevent stud protruding through lower surface. This design gives stronger welds than a shallow cone.
150° included angle cone
Achievable weld area is only up to about 90% of the stud cross-section.
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FAQ: What projection profile suits projection welding?
Best practice guide: Resistance welding of sheet metals. Please note that the guide does not cover projection welding in detail, but basic information to supplement this FAQ is available at the end of section 3.