Automotive supplier single-sources 360 welding robots

Citation

(2002), "Automotive supplier single-sources 360 welding robots", Industrial Robot, Vol. 29 No. 3. https://doi.org/10.1108/ir.2002.04929cab.012

Automotive supplier single-sources 360 welding robots

Automotive supplier single-sources 360 welding robots

Keywords: Robots, Welding

The latest £1.6 million order for 68 robots and manipulators placed on Motoman Robotics (UK) by first tier automotive supplier, TKA Chassis Tallent, Newton Aycliffe, brings the total number of Motoman welding robots on site to more than 360. It is by far the largest number of robots operating under one roof in the UK outside car plants. About 80 percent are for arc welding with the remainder devoted to spot welding applications (Plate 6).

Overall, Motoman robotic welding systems are known for their reliability. Mean time between failure is 60,000 hours provided that routine maintenance procedures are followed. Tallent has achieved this level of reliability from cells which have been triple shifted for more than ten years, despite metal inert gas (MIG) arc welding being one of the most harsh operating environments for a robot owing to the high levels of spatter, fumes and electrical noise.

Plate 6 One of the 360 Motoman welding robots in action at the Newton Aycliffe factory of TKS Chassis Tallent

Quality levels achieved by Tallent are remarkably high, thanks in part to the company's investment in effective washing of pressings and in blanking tools for trimming components to close tolerances prior to robotic welding. Maximum joint gap is precisely maintained at half wire diameter, typically 0.5mm, and positional accuracy at the welding tip is +0.8mm with ±0.5mm repeatability. This obviates the need for seam tracking, which would impose an unacceptable time penalty in this highly competitive, mass production environment.

The history of Tallent's supply of chassis components into the automotive industry is impressive and has gone hand in hand with a rolling programme of investment in Motoman robotic welding cells. Dating back to the Ford Sierra rear suspension arm project in 1982, business with automotive OEMs soon gathered pace with two more MIG cells installed the following year for welding Maestro and Montego sub-frames. Production of Jaguar's rear suspension wishbone followed two years later.

Then in 1987 the six-axis robot was introduced by Motoman, sporting the additional facility of arm rotation, allowing more complex welding routines to be performed. One spot welding robot and five MIG cells were installed for producing the Nissan Bluebird front suspension arm. The turnkey system including tooling, welding equipment and programs was put together and tested at Motoman Robotics (UK) in Banbury prior to installation at Newton Aycliffe. In the same year, Ford asked Tallent to take over welding of the Transit rear axle, hitherto made in house, and further turnkey MIG cells comprising five robots were purchased.

A succession of robotic welding installations followed in the early 1990s, starting with a £2 million, 22-robot spot and MIG installation for welding the sub frame and front suspension link of the Metro (subsequently renamed the Rover 100). Then in 1992, 16 MIG welding robots went in to a cell integrated by Pico for production of the Nissan Micra rear axle. At the same time, the first 100kg robots were delivered by Motoman to form a twin cell for spot welding Honda Civic and Rover 200 Series rear suspension arms. At the time they were the heaviest spot welds made by robots operating in the UK and were powered by 250kVA transformers.

The next year saw the phased introduction of 24 MIG welding robots for producing the rear axles for two popular Ford models, the Fiesta and Escort.

For further information contact Mike Wilkins, Sales Director, Arc & Cutting Systems, Motoman Robotics (UK) Ltd, 1 Swan Industrial Estate, Banbury, Oxfordshire OX16 8DJ, UK. Tel: 01295 272755; Fax: 01295 267127.