| 摘要 |
PURPOSE:To prevent gouging, etc. and to improve cutting property by cutting a hollow body by a laser beam from the outside periphery thereof while evacuating forcibly the gas in the hollow body. CONSTITUTION:The hollow body 2 is supported by a rotary supporting base 3 and is rotated by a motor 5 for rotation and a chuck 4. A laser nozzle 1 cuts the body 2 under rotation by a laser beam from the outside periphery thereof. A center gas for cutting (gaseous oxygen) is evacuated through a tube 9 for gas evacuation by a gas evacuation device 10. The gas 8 is made into the laminar flow state by the above-mentioned method, by which the cutting property of the hollow body such as pipe is improved. Gouging is eliminated and the dross 7 sticking to the hollow body after the cutting is discharged together with the gas 8. The sticking of the dross 7 is thus prevented. |
