hi Topheavy,With cylindrical/ circumferential welding you can...

hi Topheavy,
With cylindrical/ circumferential welding you can have it on arm that allows for up and down on different diameters.

For longitudinal welding you just run welding head along a track.
So it does allow for flexibility.

We do approx 2.5mtr dia circumferential weld (over 7mtr long) in about 18 minutes with one pass.
welds are 100% x-rayed.
To do this by hand is days of work as has to be done internally and externally which requires grinding into weld from other side for clear root, confined space entry etc and pretty much always requires rework and a second round of x-ray’s which is quite expensive.
We also do straight welds on track but that is relatively simple.