Pole position in welding technology

Paul Boughton

Franz Joachim Roßmann reports on how the latest welding technology is being used in modern motorbike production

For WP Performance Systems GmbH, success on the racetrack and the use of the most modern motorbike production methods go hand-in-hand.

No surprise then, that the company, one of Europe's largest manufacturers of motorbike chassis components, was among the first to test the MIG/MAG TPS/i power source from welding technology specialist Fronius. WP is now using more than a dozen devices from the TPS/i series for frame construction and exhaust manufacturing.

Josef Baier, production manager at WP, summarises his experiences of working with the latest welding power source from Fronius. “There is currently no comparable device on the market. That is why we always turn to the TPS/i when we need to satisfy a requirement such as guaranteed penetration, high welding speed or a totally spatter-free weld seam.”

The manufacturing specialist bases his opinion not just on the welds carried out himself, but also on the results of the widespread use of the devices in frame and exhaust manufacturing.

WP deems reliable penetration to be essential in the manufacture of motorbike frames. 98% of all the chassis welding is carried out by robots. However, the remaining 2% are in inaccessible locations and are welded by hand. “It is imperative that the required penetration is achieved reliably, even in out-of-position welding or in the case of longer stick outs”, explains Josef Baier. “This is where the penetration stabiliser of the TPS/i comes into its own.”

This feature regulates the arc extremely quickly and precisely to ensure that the penetration remains constant whenever the stick out may fluctuate.

Until now, spatter has been almost unavoidable when welding manually, even with the most advanced MIG/MAG devices. As the seams welded manually by WP during frame construction are very short, the company used to have to invest effort into cleaning them.

A fundamental change took place following the switch to TPS/i, as Josef Baier told us: “Now that we carry out the manual welding of the tubular sections of the motorbike frame exclusively with the TPS/i, we can say without any embellishment or exaggeration that the weld seams are spatter-free.”

A significant factor behind this achievement are the new LSC (Low Spatter Control) dip transfer arc characteristics which exhibit extremely high levels of arc stability.

LSC Root was specially developed for root passes. Its unique current profile ensures excellent root fusion and gap-bridging ability, especially welcome when it comes to exhausts, as the sheets used at WP are usually only a millimetre thick.

“With sheets this thin, there is always a danger that the weld seam will drop through,” notes Josef Baier. “Thanks to LSC Root, however, this is not a problem that we face.”

As with frame construction, WP never compromises on quality in the production of its exhaust systems. Josef Baier has therefore ensured that weld seams that are visible on the exhaust are always welded using a TPS/i device.

The new Fronius offering, with its higher root arc pressure and deposition rate is again to the fore in terms of welding speed, as Baier can confirm from practical experience: “With the TPS/i, our welders achieve a welding speed that is about 20% faster than before.”

With the production of frame and exhaust systems running at more than 120,000 per year, the acquisition by WP of modern welding systems pays for itself within a few months as a result of the practically non-existent reworking requirement and t higher levels of productivity.

Having installed the Fronius TPS/i at every workplace where spatter-free weld seams are required, Baier enjoys the full support of his employees, “Once they've tried it, our welders seem reluctant to use anything else.”