The copper It is a metal that brings together a variety of advantages (low cost, light, malleable, safe, easy to join, corrosion resistant) and is widely used in water, heating and cooling installations in residential and commercial buildings.
Like the welding of other metals, for the union of copper tubes or pipes The gas welding process with two techniques available, depending on conditions and application: soft (or conventional) welding and brazing. The soft soldering it is the most suitable for plumbing (or plumbing) and gas installations; the brazing It is the standard technique in the refrigeration and air conditioning sector.
In the techniques of soft soldering Y strong the parts to be welded do not melt, therefore a filler material (usually alloys based on tin, copper, lead, silver or zinc, depending on the technique and application) and the heat to melt this filler metal -whose magnitude depends on the technique used- can be generated by gas or electricity.
The gas welding uses a flame provided by a torch that melts the filler material and allows it to be conducted by capillary action to the surfaces to be welded, which have been previously coated with a flux suitable. The torch fuel is usually acetylene-oxygen, propane-oxygen or one gas and air mixture. In cases where the presence of an open flame is dangerous (eg gas pipes) the necessary heat can be generated by tools that work with electric resistance and that use electrodes.
Except for the differences that distinguish the soft soldering of the brazing (composition of filler material, type and composition of flux, and magnitude of heat required to melt filler material) both techniques are applied in the same way to solder copper pipes and require a series of Steps in common.
Those steps are detailed in the following table:
The two videos that follow put all these steps into practice with great clarity in the explanations, both for the soft soldering as the brazing from copper tubes or pipes, and provide helpful tips for hobbyists and beginners.