The 6kW CO2 slab laser was showcased at the Schweissen und Schneiden exhibition in Essen, Germany, performing high speed laser-spot welding of automotive seat backs. The new Remote Welding System ('RWS') was one of the highlights among the exhibits. It now has a larger working space. The system features the Rofin DC 060 W, a CO2 Slab laser, with an average output power of 6kW.
At the trade show, passenger vehicle seat backs were welded live using the system. The RWS is capable of implementing highly flexible, multiple spot welds at high speeds within a large work area.
Version diversity in the welding geometry is unlimited. Based on simple programming, all requirements such as circles, dots, lines, waves or any other forms, can be met in a short time, The laser beam of the RWS is expanded with a telescope focused inside the workspace by optics at a focal distance of up to 2m to enable processing in a large work area.
The coordinates of the X and Y axis are controlled through a rotating mirror and focal point positioning occurs through these optics in the Z axis via the assembly on a linear motion slide. An additional traverse movement of this mirror along the Y axis expands the work area. Rapid traverse motion between individual processing points, known as rapid move, enables high -speed multiple spot weld applications.
Compared to conventional spot welding, these rapid moves provide substantial reductions in cycle times. The rapid move concept enhances machine availability and process optimisation. The system has an edge over conventional processes which use mechanical axle drives and numerous spot welding guns. The system can achieve nearly 20 million welding cycles at more than 300km of weld joint lengths in a three shift operation, without necessitating the replacement of typical system wear parts.
Optimisation of the production process is achieved in terms of time and cost with the option to undertake an x-amount of joint versions, eliminating the need for adjusting and clamping operations and due to the high speed.
The RWS will be showcased at the trade show in combination with a diffusion-cooled CO2 Slab laser from Rofin's DC series, the Rofin DC 060 W, which is a laser with good beam quality. A high energy density must be especially guaranteed for very long focal distances. Only high power outputs at high beam quality (<5mm x mrad) enable the economically logical use of wide-range remote welding. The term remote is obtained from the great distance between the work piece and the optical components.
The lasers of the DC product family possess a perfect fundamental mode structure over the entire performance range, producing an energy density even at great focus distances, which contribute to the high welding speeds.
A working range of 2.9 x 1.8 x 1.0m therefore results at a focusing distance of 2000mm. A compact version will be showcased at the trade show, since the low dimensions of the laser head of the DC 060 W enable a placement above the processing cell. Thus, a complete system is generated with minimal space requirements, suitable for the processing of larger components or assemblies. Particularly in the field of Automotive vehicle body manufacturing (body in white), designs require increased accessibility during processing. Welding positions are made possible by the flexible positioning capability of the laser beam, which resistance spot welding cannot achieve.
The product is available from Laser Resources .