Any weld that can be economically automated should be. Several years ago I worked a project to help a supplier implement automated orbital tube welding for an aerospace product. There were two of these welds per part, and 8 parts per airplane, for an airplane that was being produced at around 50 per month. So they needed to make about 800 welds per month, about 37 per day. Including setup, each manual weld took around 15 minute, so over 9 hours of welding the exact same setup over and over, while being exposed to hot surfaces, UV light, and welding gasses. That's no job for a human.