Premium
Tool wear in TBM hard rock drilling – backgrounds and special phenomena
Author(s) -
Ellecosta Peter,
Käsling Heiko,
Thuro Kurosch
Publication year - 2018
Publication title -
geomechanics and tunnelling
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.317
H-Index - 18
eISSN - 1865-7389
pISSN - 1865-7362
DOI - 10.1002/geot.201800006
Subject(s) - abrasive , drilling , tapering , tribology , fracture (geology) , bearing (navigation) , brittleness , cutting tool , geology , mechanical engineering , engineering , computer science , materials science , geotechnical engineering , metallurgy , artificial intelligence , computer graphics (images)
Abstract In hard rock TBM drilling, wear issues play a crucial role in the success of a tunnelling project. Thus, excavation tools must be selected carefully and be adapted to ground conditions. Wear‐related changes in the tools that occur over the course of the tools' operating lives must also be taken into account. This paper presents five basic types of macroscopic wear for cutter rings: (1) abrasive/normal wear, (2) tapering, (3) mushrooming, (4) brittle fracture of the cutter ring (special wear type 1) and (5) blockade of the roller bearing (special wear type 2). These basic wear types lead to distinct cutter ring shapes which allow deriving some fundamental characteristics of the interacting rock types. In addition, a microscopic analysis of the surfaces and associated metallographic sections from worn cutter tools has been performed. As a result, the tribological processes under the cutter, leading to tool wear, can be better understood. In summary, the investigations may contribute to a better understanding to make it easier to choose the proper TBM disc cutter for a distinct rock type in order to minimize the risk of tool‐related downtimes.