The use of laser techniques such as CO2-laser-GMA-hybrid longitudinal or spiral welding have been investigated for the production of pipes in a variety of steel grades. In such applications the robustness, mobility and high degree of freedom offered by fibre delivery, gives the fibre laser advantages over the CO2 laser, yet it has not been widely used to date.
Here we present results for fibre laser-GMA-hybrid welding of pipe steel as a way of welding 14 mm thick section X70 material with the maximum of 8 kW laser power available. Two different wire electrodes were tested for their suitability in this application.
The equipment comprised a fibre laser source, a welding head combined with a welding torch and a welding source with a wire feed unit. Details of equipment and materials can be found in the highlighted box opposite and figure 1 shows the arrangement. For these tests the pipe material was supplied in plate form.