Soldering

Soldering refers to a group of joining processes that produces the coalescence of materials by heating them to the soldering temperature in the presence of a soldering filler metal having a liquidus below 840°F (450°C) and below the solidus of the base metal, i.e. without melting of the base metal.

The soldering filler metal can be used to seal the joint, but should not be expected to provide a mechanically strong joint or carry the structural load. Mechanical strength needs to be provided for by another means of reinforcement, such as lock seaming, riveting, spot welding, or bolting. Visual inspection is usually sufficient for evaluating the quality of a soldered joint.

The soldered metal should be smooth and continuous; lumps or other visual discontinuities are indicative of insufficient heat. Holes are most likely caused by contamination or overheating, and can result in leaks.