Full-scale linear cutting experiments with a conical cutter for simulating different cutting patterns

This study aims at comparing experimentally single, double, and triple spiral (scroll) cutting patterns for improving performance prediction models based on linear cutting tests. Full-scale linear cutting tests are performed by using a heavy duty conical cutting tool used mostly with roadheaders, shearers, continuous miners, and surface miners. The tests are performed at line spacing of 25 mm and varying cutting depths per revolution by using a travertine sample, which is considered as ductile and soft. Comparison criteria are average normal, cutting, and side forces, specific energy, and yield. Preliminary results indicate that normal forces increase highly with increasing spiral number, which is important for thrust limitation of miners, while cutting force and specific energy increase slightly. Results indicate that it is better to use lower number of spirals for soft and ductile rocks. However, additional tests are continuing to generalize the results including different types and strengths of rocks.