TPT May 2008

T ube & P ipe W elding: T rends & P rogress

New generation of pulsed YAG lasers

Rofin, Germany, has launched StarPulse, a new generation of pulsed YAG rod lasers with power ratings ranging from 40 to 500W, which introduce a number of new product technologies. For laser welding of highly reflective materials like copper or aluminium and materials with high melting temperatures, high pulse peak powers are required. The StarPulse lasers provide high peak powers

up to 20kW. Welding of components with high thermal conductivity can be achieved with large welding depths and high process speeds. The control of the StarPulse lasers is based on Rofin’s new RCU control unit. The RCU achieves power control with the Double Closed Loop TM method. The double closed loop guarantees pulse- to-pulse stability and intra-pulse control

 Simple and efficient operation via touch panel

independent of back reflections from the workpiece. With precisely controlled laser pulses down to a few mJ of pulse energy, welding of extremely thin wires (diameters down to 50 μ m and smaller) used in the medical device and electronics industry, or seam welding of the finest thin-walled metal parts is possible. The Double Closed Loop allows optimal adjustment of the so called Shadow technology – a quasi cw-welding – to the user’s process. The entire weld seam is produced by a single laser pulse at a high feed rate. The benefits of this method, which is particularly suitable for micro and fine mechanics products, are reduced thermal strain and higher process stability, compared to spot welding. The graphical display of the measured pulse on the Real Time Application Monitor™ allows online control of each pulse. This feature is beneficial for processing alloys

 StarPulse provides welding via pulse-to-pulse stability

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M ay 2008

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