BMW Mini production uses tactile laser welding

Oxford, UK - BMW's Mini plant is receiving the bulk of a 2012 to 2015 spend of 750 M pounds - also shared with the pressings factory in Swindon and engine facility at Hams Hall - primarily to produce the redesigned hatchback and Clubman versions, according to an article by Graeme Roberts, a news editor of just-auto.com.

The one-time Pressed Steel plant at Cowley, which BMW bills as Plant Oxford, has received a new body shop and upgrades to quality processes and the paint shop. Plant Swindon - also a former Pressed Steel factory - has introduced three new body manufacturing tricks and generally improved productivity.

Tactile laser welding is used to make the bonnet from eight pressed parts. The bonnet's outer panel is bent to touch the mating flange on the inner panel and joining uses a fine weld wire on the laser. Panels were previously roller-hemmed together with adhesive and seam sealer, but there was always the possibility of a void forming that could allow condensation to develop. A remote laser can produce long continuous joints of greater precision, a process quicker than spot welding and a group first.

Up to five different door designs can now be produced in the same production cell by the same set of robots using a new fixture holding system. A new linear change system for switching the tooling from one model to another has also increased efficiency.

Mini Cooper S Photo courtesy of BMW