How should the ends of pipes be prepared for joining during silver brazing?

For successful silver brazing, preparing the ends of pipes properly is crucial. The practice of rounding the ends of the pipes with an expander ensures that they fit together snugly and uniformly. This preparation helps establish a consistent gap between the two surfaces that will be joined, which is essential for the effective flow of the filler metal during the brazing process. Rounded edges can help minimize stress concentrations and improve the overall strength and integrity of the joint.

When pipe ends are rounded, it also facilitates better heat distribution and allows the filler metal to penetrate effectively into the joint, creating a strong bond. Therefore, using an expander to round the pipe ends is a vital step in preparing them for brazing, supporting the formation of robust and reliable connections.