Laser Systems Europe
Type: Zeitschriftenaufsatz (non-reviewed)
In addition to conventional welding, laser-arc hybrid welding processes have recently been used in the maritime sector for existing joining tasks. In the area of high steel plate thicknesses exceeding 12mm, however, no new welding processes have been established in recent decades, leaving considerable need for innovative, efficient joining technologies. The introduction of a high-power diode laser beam source with an optical output power of up to 60kW (LDF 60.000-200, Laserline) creates promise for using new, robust laser welding processes for high-quality joints in the thick sheet range up to 30mm at high speeds. Such processes are now being developed through close cooperation between industrial and scientific partners. In tandem with developing such processes, a concept for ensuring laser safety has to be determined that will adequately protect personnel in the vicinity of the operation. In particular, the strong scattered radiation from the laser process zone has to be considered in order to be able to comply with the exposure limit values not only for the eye, but also for the skin, according to Directive 2006/25/EC. The extent and spatial distribution of the scattered radiation emission has therefore been determined, and the thermal load of the vicinity of the process zone estimated4 using a simple mathematical model, yielding distance-dependent average temperatures of the material of the local shielding. Here we have derived and provided recommendations for the design of the protective enclosure.