What is Welding?

Welding is a joining process in which metals, or sometimes plastics, are heated, melted and mixed to produce a joint with properties similar to those of the materials being joined.

Welding is the most economical and efficient way to join metals permanently. It is the only way of joining two or more pieces of metal to make them act as a single piece. Most commonly, workpieces are welded by melting both of them and adding more molten metal or plastic to form a pool that cools to form a strong joint.

The energy to form the joint between metal workpieces most often comes from a flame (e.g. oxy-acetylene) or an electric arc. Most welding involves ferrous-based metals such as steel and stainless steel. Welding covers a temperature range of 1500º F - 3000º F. Weld joints are usually stronger or as strong as the base metals being joined. There are many ways to make a weld and many different kinds of welds.

Some processes cause sparks and others do not even require extra heat. Welding can be done anywhere… outdoors or indoors, underwater and in outer space. Metals can also be cut or separated by a flame or an electric arc, or removed by "gouging" with an electric arc.

Brazing is the joining of metals with a filler metal having a melting point above 450°C (842°F), but below the melting point of base metals. Soldering is the joining of metals using a filler metal with a melting point below 450°C (842°F). The joined metals can be different metals. The "filler" metals commonly used are lead-tin alloys.