What is the effect of using nitrogen in the piping during a brazing operation?

Using nitrogen in the piping during a brazing operation is primarily beneficial because it prevents copper oxide formation. When brazing, the extreme temperatures can cause copper to oxidize, leading to the creation of copper oxide on the surface of the metal. This oxide layer can significantly impair the quality of the brazed joint by preventing proper adhesion of the filler metal, which can lead to weak joints that may fail under stress.

By flushing the piping with nitrogen, a non-oxidizing gas, the oxygen that would typically contribute to oxidation is displaced. This controlled atmosphere allows for cleaner surfaces to be joined, resulting in stronger and more reliable connections in the piping system. Thus, utilizing nitrogen is a critical step in ensuring that the integrity of the joint is maintained during the brazing process.