KTM automates TIG welding of motorcycle frame parts

Citation

(2009), "KTM automates TIG welding of motorcycle frame parts", Industrial Robot, Vol. 36 No. 2. https://doi.org/10.1108/ir.2009.04936baf.003

KTM automates TIG welding of motorcycle frame parts

Article Type: Mini features From: Industrial Robot: An International Journal, Volume 36, Issue 2

Automation of the production processes has always been one of the most pressing and important objectives for metal-working companies. KTM, the motorcycle manufacturer based in Mattighofen, Austria, has found a solution for joining frame sections for its sought-after new product, the RC8. This solution offers a 90 per cent degree of automation. With regard to strength, independent test engineers have declared themselves satisfied with the results, which also meet the strict criteria of both the commercial managers at KTM and the motorcycling fraternity. The various technical experts have responded positively to the MagicWave 4000 system from Fronius (Figure 2).

Figure 2 A robot uses a MagicWave 4000 system to weld fillet seams and single-V butt seams with 2 mm gaps for motorcycle frames at KTM

The RC8 road bike is one of KTM’s latest and most successful models. Not only do the weld seams need to be strong, but they also need to look good too. All the joins in the RC8 frame are therefore tungsten inert gas (TIG)-welded. The traditional rippled TIG weld seam conveys the sense of prestige and quality that end customers are always looking for. However, the high-seam quality that TIG welding provides does have one drawback: relatively low productivity. This is generally some two-thirds below that achieved using the more modern metal active gas (MAG) welding methods.

KTM’s technical experts have devoted three years to this development project, and the end result is 90 per cent automation of frame production. They eventually made good a significant amount of the productivity shortcomings of TIG compared with the MAG process. Since the start of 2008, the robot welding plant where the RC8 frames are welded has been working at full capacity on a three-shift system.

Josef Baier, Production Manager at KTM, reports: “This way we can produce particularly fine, clean TIG seams. The components used are 1.2 mm sheets and tubing made from a type of material designated 25 CrMo4. Our welding system of choice is MagicWave from Fronius”.

A special in-house developed pallet feeding system feeds the subassemblies to the ABB robot until the frame is complete. The effective throat thickness of the fillet and single-V butt welds is 2 mm, and the gaps to be bridged are 2 mm wide. The “heart and soul” of the racing machine, which consists of joined tubing sections, can withstand the mechanical and dynamic stress of being driven on a road or around a motocross track.

The reason that TIG welding is so successful from a technical point of view is its virtually perfect weld toe.

The “pulses” that are typical of the TIG method cause the filler material to melt on in the form of a series of scallops. The use in TIG pulse welding of the relatively high, but accurately controlled heat input, allows gaps to be bridged effectively and perfect roots to be achieved. Fusion at the start and end of a seam is greatly improved, especially when welding tubes.