This is a common method for joining the cooper tubing.It is have been practice by all technical person around the world.Before we can brazing the cooper tubing,we must do the swagging process for make a diameter of cooper bigger than normal size.
Refer my last post about swagging.It is for ensure the joining process is strong and no leakage.Others method is using the cooper fitting or socket joint to make a joining process.Below illustration it is the cooper piping structure after done the swagging process and ready to brazing process.Make sure the swagging process is perfectly to get a best result of joining. read more