Puddle Welds -

1. Definition and Basic Concept A puddle weld is a welding process used to join two or more overlapping metal components, typically sheets or plates, by depositing weld metal into a pre-drilled or pre-punched hole in the top layer(s). The weld penetrates through the hole and fuses with the bottom layer, creating a solid, localized connection.

The term "puddle" refers to the molten weld pool that forms in the hole, which solidifies to form the joint. Unlike continuous seam welding, puddle welds are intermittent, circular connections. puddle welds

| Parameter | Typical Value / Rule | |-----------|----------------------| | Hole diameter (D) | Equal to the thickness of the top plate (t), but not less than 8 mm (5/16") for structural steel. For thin sheet, often 5–8 mm. | | Minimum hole diameter | Should be at least the thickness of the top plate + 1.6 mm (1/16") to allow access. | | Maximum hole diameter | Should not exceed 2.5 × thickness of the top plate, or the weld pool becomes too large to control. | | Plate thickness range | Best for top plates ≤ 10 mm (3/8"). For thicker top plates, bevel the hole edge. | | Spacing between welds | Typically 4× to 6× the hole diameter center-to-center. | | Edge distance | At least 1.5× hole diameter from the edge of the sheet. | The term "puddle" refers to the molten weld