| 摘要 |
PROBLEM TO BE SOLVED: To execute underwater laser cutting on a cutting object having irregularity on a surface.SOLUTION: A separate distance up to an area of generating the scattered light of an effective range measuring laser L2 from a nozzle 8, is detected by a test for emitting the effective range measuring laser L2 and injecting assist gas G from the nozzle 8 of a laser torch 2. Data of relating a stand-off value set based on its separate distance, the water depth for executing underwater laser cutting work, a diameter of the nozzle 8, pressure and a flow rate of the assist gas G supplied to the laser torch 2 from assist gas supply means 5, is prestored in a database 23 of a control device 7. When executing underwater laser cutting, a preset value of the pressure and the flow rate of the assist gas G supplied to the laser torch 2 is called out of the database 23 based on the water depth for arranging a cutting object W and a stand-off condition, and the assist gas G is supplied to the laser torch 2 by its pressure and flow rate.SELECTED DRAWING: Figure 1 |
