However, I have noted that in areas where building-trade unions aren't as strong, classes are being taught more frequently by industry people with little or no apprenticeship training and who may be long on service skills but who are generally weak when it comes to proper piping practices. And this is having an effect on the reliability of the equipment. What am I talking about?
What does the flow of dry nitrogen do when brazing? Well, if there is no oxygen inside the lines, there is no oxidation, so no corrosion is formed. In addition, dry nitrogen keeps moisture-laden air out of the lines during installation, making the dehydration (evacuation) process go much faster.