Welding joints vary widely but can be traced back to a few basic joint types.  Typically we hear terms like fillet weld, butt weld, lap weld or corner weld.  These are all all joints but within these there are variations.  Below we outline the joints and provide a graphical representation.  These joint types are categorized by how the plates come together, and further subcategorized by joint preparation.

BUTT JOINTS

Butt joints consist of placing two plates side by side and joining to create a single piece.  When plate thickness increases, or full penetration is desired, the plates are beveled. These are referred to as groove welds.  Beveling increases the amount of filler metal needed but insures higher strength and proper penetration.

TEE JOINTS (FILLET WELDS)

The tee joint has variations when a one of the pieces is beveled. As with butt welds, the bevel is used to achieved deeper or full penetration.  It also requires less weld for equal strength on heavier sections.

CORNER WELDS

Corner welds are used to joint plates at 90 degree angles.  Depending on material thickness it can be a straight butt weld, a lap weld, a fillet weld, or a groove weld.

LAP WELDS

Lap welds are  similar to fillet welds but the the size of the fillet typically reaches the top of one of the pieces.

EDGE WELDS