Experimental investigation of cutting performance for cast iron pipe in utility tunnel

The aging of utility tunnels is accelerating, and the deterioration of essential internal facilities, such as pipelines, is becoming a serious issue. Pipe cutting is essential for replacing aging pipes. However, no system exists for use inside utility tunnels. This study investigated the pipe-cutting performance of waterjet cutters, laser cutters, and diamond wire saws according to the standardized energy. A literature review was conducted to examine the cutting performance of cast iron based on the energy input of each cutting technology, and the findings were experimentally validated. Cutting tests on 20 mm ductile cast iron specimens revealed that a waterjet cutter required an effective kinetic energy of 60 J for a complete cut. For the laser cutter, a complete cut of 20 mm ductile cast iron was achieved at a laser power of 3,000 W, which is the primary performance variable. The diamond wire saw demonstrated limited applicability for cutting metallic materials, making it difficult to verify the cutting performance based on the energy input, so further experiments were deemed necessary. Finally, the minimum energy input required for 20 mm cast iron cutting has been determined. Moreover, the technical limitations and challenges associated with the practical application and optimization of each cutting technologies within utility tunnels were discussed. These findings provide fundamental data for evaluating the cast iron cutting performance of technologies, thereby contributing to the future development of equipment for cutting aging pipes.