WHEN MILLIMETRES MAKE THE DIFEERENCE

摘要

DISC CUTTERS ARE UBIQUITOUS in hard rock TBM tunnels; however, their performance is anything but. What can make the difference between frequent downtime to replace the discs and fast excavation with long-lasting cutters is often the small details. In fact, success can be a game of millimetres when it comes to disc cutters. Results that have borne out in the laboratory-a 508mm- (20-inch-) diameter cutter has 60 per cent more wear volume than a 483mm- (19-inch-) diameter cutter, for example-are being backed by more and more studies in the field. A difference like that can result in dramatic increases in cutter life, even in very hard rock. What's more than that, differences in processing of the tool steel between different manufacturers can further affect cutter life by reducing wear.