Weld joint type

Edge Joint

An edge joint lays two members face to face and welds along their common edge — a light-duty joint used to join flanges and sheet edges, not to carry load.

Edge joint cross-section Cross-section through a edge joint. Parallel members welded along a common edge
Cross-section through a edge joint.

Geometry and preparation

ConfigurationTwo parallel or nearly parallel members with their edges aligned, welded along that common edge.
Edge preparationUsually none. Thicker members may be bevelled into a V or J groove along the edge.
StrengthLow. The weld is not in the load path in any useful direction, so edge joints are used for sealing, alignment and light assembly rather than for transferring structural load.

Characteristics

  • Among the easiest joints to weld: the two edges sit right at the top of the puddle.
  • Frequently welded autogenously — fusing the edges together with no filler metal at all.
  • Not a load-bearing configuration; the weld carries very little in tension or shear.
  • Used to seal seams, join flanges and hold light assemblies in alignment.
  • On thin sheet, it is one of the few joints where a TIG torch alone with no filler gives a clean, finished result.

Weld types used on a edge joint

Where it is used

  • Sheet metal flanges and seams
  • Light enclosures and covers
  • Tanks and ducting where the joint seals rather than carries load
  • Assembly tacking and alignment

Edge Joint — common questions

Is an edge joint strong?

No. It is a light-duty configuration used for sealing, alignment and assembly. Where load has to be transferred, a butt, lap or T-joint is used instead.

Can you weld an edge joint without filler metal?

Yes — on thin sheet, the two edges can be fused autogenously with a TIG torch. It is one of the few joints where that works cleanly.

When would you use an edge joint?

Joining flanges, sealing sheet metal seams, and light assembly work where the weld holds parts in position rather than carrying structural load.

Does an edge joint need preparation?

Usually none. On thicker members the edge may be bevelled into a V or J groove so the weld reaches the full thickness rather than just fusing the top.

Other joint types