When butt welding pipe, a backing ring is used to:

When performing butt welding on pipe, using a backing ring is primarily intended to align the pipe sections effectively. Proper alignment is critical to achieving a strong, continuous weld along the joint. The backing ring provides a physical support that helps maintain the correct distance and position between the two pipe ends during the welding process, ensuring that the weld bead can be applied uniformly.

While aligning the pipes, it also assists in creating a smoother and more consistent welding arc, which is essential for strong weld integrity. This alignment is particularly important in applications where the pipes will be subjected to various stresses and pressures, as misalignment can lead to weak spots that may fail over time.

The other functions of backing rings, such as reducing the amount of welding rod required or reinforcing the pipe joint, are not their main purposes. The backing ring's role in preventing welding gases from entering the pipeline is limited as well, with proper technique and equipment generally ensuring the prevention of such occurrences.