Small to medium fabrications in batches too short for a conventional cell but too repetitive to enjoy welding by hand - frames, brackets, enclosures, tanks and weldments in tens rather than thousands. The practical test is whether a simple fixture can present the part consistently and whether the joints fall inside the arm's reach from one setup.

For a straightforward linear or circular joint, minutes. The operator hand-guides the arm to the start and end points, sets a schedule, and runs it. Complex multi-pass work, weaving patterns and parts needing several approach angles take longer, and are where the time advantage over pendant teaching narrows.

Not usually for the robot motion itself, provided the collaborative application passes a risk assessment covering speed, force and the torch as a sharp hot tool. You do still need protection from the arc: welding screens or curtains against radiation, and fume extraction. Treat the guarding question as being about the process, not the arm.

Predominantly GMAW with solid or flux-cored wire, because continuous feed suits automation and the power sources are compact. Cobot TIG packages exist and are used on thin stainless and aluminium where appearance matters, accepting slower travel. The power source is normally matched and communicating with the arm rather than a generic machine.

That is a large part of the appeal. Cart-mounted systems are wheeled to the work, clamped or levelled, and recalibrated to the fixture. Programs stored against a fixture reference can be recalled after the move. Repeatability depends entirely on re-establishing the same relation between arm and part, which is what the reference and fixture provide.

The same as any taught robot: it welds where it was told, not where the joint is. Consistent gap and part placement matter more than with a manual welder, who compensates continuously. Some systems offer touch sensing or through-arc tracking to absorb variation, and simple, positive-location fixturing solves most of the rest.

It does not replace the judgement a welder brings to fit-up, repair and one-off work, and it still needs someone to load, fixture and inspect. What it adds is consistent arc time on repetitive joints, freeing a skilled welder for work that needs skill. Shops generally report it as capacity relief rather than headcount reduction.