Wear of Rock Cutting Tools

Preface -- 1 Introduction -- 2 Rock cutting theories -- 3 Possible wear mechanisms at the wear-flat of rock cutting tools -- 3.1 Introduction -- 3.2 Wear type classifications -- 3.2.1 The motion category classification -- 3.2.2 The wear mechanism classification -- 3.3 Wear mechanisms relevant to rock cutting tools -- 3.3.1 Abrasive wear -- 3.3.2 Adhesive wear -- 3.3.3 Sliding wear -- 3.3.4 Total wear due to sliding motion contact -- 4 Wear mode hypothesis -- 4.1 Introduction -- 4.2 Cutting forces -- 4.2.1 Influences of rock material properties on cutting forces -- 4.2.2 Influences of rock mass properties on cutting forces -- 4.2.3 The influence of some operating condition factors on cutting forces -- 4.3 Rock relief strength -- 4.3.1 The influence of rock material strengin properties on relief strength -- 4.3.2 The influence of the geometry of the relief on relief strength -- 4.3.3 Hardness of the mineral grains -- 4.4 Wear mode prevalence -- 5 Rock cutting tests to study wear -- 5.1 Introduction -- 5.2 The scraping test -- 6 Rock properties with respect to wear -- 6.1 Introduction -- 6.1.1 Rock property based rock cutting wear index values -- 6.1.2 Some considerations on the non-intrinsic rock property parameters -- 7 Experiments -- 7.1 Introduction -- 7.2 Scraping test experiments -- 8 Chisels used in the experiments -- 8.1 Introduction -- 8.2 Chisel material -- 8.3 Chisel shape -- 8.4 Thermocouple -- 9 Properties of rock types used in the experiments -- 9.1 Rock material properties -- 9.1.1 Interpretation of the measured and derived rock properties -- 9.2 Rock sample preparation -- 10 Test results on artificial rock (mortar) -- 10.1 Repeatability and the effect of groove spacing -- 10.1.1 Effect of spacing of the grooves, sawn into the rock disc -- 10.1.2 Repeatability of the experiments, with respect to the amount of wear -- 10.2 Scraping test experiments on mortar at constant cutting velocity -- 10.2.1 Experiments on mortar composition I -- 10.2.2 Results of experiments on three mortars of different strength -- 10.2.3 Results of experiments on four mortars of different grain size -- 10.2.4 Results of experiments on three mortars of different volume percentage of abrasive grains -- 10.2.5 Results of experiments on two mortars of different shape of the quartz grains -- 10.2.6 Results of experiments on mortars of different mineral content -- 10.3 Specific wear equations based upon scraping test experiments on morta -- 10.4 Scraping test experiments on mortar with varying cutting velocity -- 10.4.1 Experiments on mortar composition 8 -- 10.4.2 Experiments on different mortars -- 10.5 Comments on the experiments on artificial rock (mortar) -- 11 Test results on natural rock types -- 11.1 Introduction -- 11.2 Experimental results -- 11.2.1 Experiments on sandstones -- 11.2.2 Experiments on limestones -- 11.2.3 Correlation of test results obtained in experiments on artificial or natural rock -- 11.3 Comments on the experiments on natural rock -- 12 Relation of the scraping tests with rock cutting projects in practice -- 12.1 Description of the T-850 rock cutting trencher -- 12.2 Calculation of the feed of a single bit of the T-850 rock cutting trencher -- 12.3 The specific wear in the schnarrtanne granite and the oberdorfer sandstone, predicted on the basis of results from the scraping test experiments -- 12.4 Comparison of the field results with the experimental results -- 13 Conclusions -- 14 Closing remarks and recommendations -- Nomenclature -- List of abbreviations and symbols -- References -- Appendix I: Comparison of porosity values determined by different methods -- Appendix II: Petrographic descripitions -- Appendix III: Momentary cutting forces in tests on Elb-sandstone D.