Rotary Drilling and Blasting in Large Surface Mines

Rotary Drilling and Blasting in Large Surface Mines......Page 2
Dedication......Page 6
Contents......Page 8
Foreword......Page 26
Preface......Page 28
Credits for illustrations......Page 32
1.2.1 Recovery of minerals or crushed rock......Page 36
1.3 STRENGTH OF ROCK MASS AND CLASSES......Page 38
1.4 DRILL AND BLAST OPERATIONS......Page 39
1.5.2 Machine digging......Page 42
1.5.3 Ripping......Page 43
1.5.4 Rock breaking......Page 46
1.6 OILWELL DRILLING......Page 47
2.1 INTRODUCTION......Page 50
2.2 BASIC CONCEPTS OF DRILLING......Page 51
2.3 PECULIARITIES OF BLASTHOLE DRILLING......Page 57
2.4 COMPARISON OF DRILLING METHODS......Page 58
2.5 CHOICE OF A BLASTHOLE DRILLING METHOD......Page 62
3.2 EARTH AND ITS INTERIOR......Page 66
3.3 GEOLOGICAL CYCLE......Page 69
3.3.1 Igneous rocks......Page 70
3.3.2 Sedimentary rocks......Page 71
3.3.3 Metamorphic rocks......Page 72
3.3.3.4 Impact metamorphism......Page 73
3.4.2 Plutonic structures......Page 75
3.5 SOILS, ROCKS AND THEIR PROFILE......Page 78
3.6 OCCURRENCE OF MINERALS......Page 79
3.7 ROCK SPECIMEN PROPERTIES......Page 81
3.7.2 Compressive strength......Page 82
3.7.3 Tensile strength......Page 85
3.7.4 Hardness......Page 87
3.7.4.1 Shore hardness......Page 88
3.7.6 Brittleness......Page 89
3.7.7 Coefficient of internal friction......Page 90
3.7.9.1 Cerchar abrasiveness test......Page 92
3.7.9.2 Miniature drill test......Page 93
3.7.9.3 Bit wear test......Page 95
4.2 ERA OF SHOT HOLE DRILLING......Page 96
4.3 ROTARY DRILLING......Page 98
4.4 ROTARY BLASTHOLE DRILLING......Page 106
4.5 TRUCK MOUNTED ROTARY BLASTHOLE DRILLS......Page 115
5.2.1 Blade bits......Page 118
5.2.3 Feed force and rotation of drag bits......Page 120
5.3 TRICONE BITS......Page 121
5.3.1 Types and nomenclature......Page 122
5.3.2.1.1 Air cooled tricone bits......Page 126
5.3.2.1.2 Sealed bearing bits......Page 129
5.3.2.3 Cone size......Page 130
5.3.2.4 Number of teeth......Page 133
5.3.2.5 Cone orientation......Page 134
5.3.3 Metallurgy......Page 135
5.3.3.1 Materials......Page 136
5.3.3.2 Heat treatment......Page 137
5.3.4 Summary of design features......Page 138
5.3.6 IADC code......Page 140
5.4 DULL BIT ANALYSIS......Page 142
5.4.1.3 Observation at final bit rejection......Page 143
5.5.1 General data......Page 144
5.5.5 Bit discard details......Page 146
5.6 BIT FAILURE ANALYSIS AND REMEDY......Page 147
5.7 DISCARDING DRILL BITS......Page 149
6.2 DRILL PIPES......Page 152
6.2.2 Fabricated drill pipes......Page 153
6.2.3 Choice of a drill pipe......Page 157
6.3 STABILIZERS......Page 158
6.3.1 Replaceable sleeve stabilizers......Page 160
6.3.3 Integral blade stabilizers......Page 161
6.3.4 Roller stabilizers......Page 162
6.5 SHOCK ABSORBERS......Page 163
6.5.1 External shock absorber......Page 165
6.5.2 In the hole shock absorbers......Page 167
6.6.3 Blasthole plugs......Page 169
6.6.5 Drill stem wrench......Page 171
6.6.7 Blasthole inclinometer......Page 172
6.6.8 Blasthole camera......Page 174
6.6.9 Feed force measuring kit......Page 176
6.6.10 Blasthole dewatering pump......Page 178
6.6.11 Recovery tools......Page 179
6.6.12 Blasthole sampler......Page 180
6.6.13 Laser measuring instruments......Page 182
6.7.5 Safety vest......Page 185
6.7.8 Face shield......Page 186
7.2 ASSEMBLIES IN ROTARY BLASTHOLE DRILLS......Page 188
7.2.1 Assembly placement......Page 190
7.3 TYPES OF ROTARY BLASTHOLE DRILLS......Page 191
7.3.1 Special purpose rotary blasthole drills......Page 192
7.3.2.2 Carrier mounted rotary blasthole drills......Page 195
7.3.2.3 Comparison of crawler vs. carrier......Page 196
7.5.1.1 Carrier undercarriage......Page 198
7.5.1.2.1 Slewing crawler undercarriage......Page 201
7.5.1.2.3 Crawler track components......Page 204
TRACK PADS......Page 205
7.5.2 Assemblies in the upper group......Page 207
7.5.2.1 Main frame......Page 208
7.5.2.2 Leveling jacks......Page 209
7.5.2.3 Prime mover......Page 210
7.5.2.4 Compressor......Page 211
7.5.2.6 Bit lubricating system......Page 212
7.5.2.7 Automatic lubrication system......Page 213
7.5.2.10 Dust control system......Page 216
7.5.2.11 Operator's cab......Page 221
7.5.2.12 Driver's cab......Page 223
7.5.3 Assemblies in the mast group......Page 224
7.5.3.1 Mast......Page 225
7.5.3.4.1 Carousel pipe changers......Page 226
7.5.3.4.2 Single pipe changers......Page 229
7.5.3.6 Angle hole attachments......Page 231
7.5.3.7 Rotary head......Page 233
7.5.3.8.2 Hydraulic cylinder and wire rope......Page 235
7.5.3.8.4 Fixed sprockets and chain......Page 236
7.5.3.8.5 Rack and pinion with chain......Page 237
7.5.3.8.6 Chainless rack and pinion......Page 238
7.5.3.10 Tool handling jib......Page 239
7.5.4 Special purpose items......Page 240
7.5.4.2 Lighting......Page 241
7.5.4.3 Fast fuel fill system......Page 242
7.5.4.5 Fast retract system......Page 244
7.5.4.7 Fire extinguishers......Page 245
7.5.4.8 Automatic fire suppression system......Page 247
7.5.4.10 Automatic leveling system......Page 248
7.5.4.11 Remote propel control......Page 249
7.5.4.15 Video camera system......Page 250
7.6.1 Engine starting aid......Page 252
7.6.3 Double wall machinery house......Page 253
7.6.6 Other enclosures and heaters......Page 254
7.7 COMPARISON OF TYPES OF BLASTHOLE DRILLS......Page 255
8.2 COMPRESSED AIR......Page 258
8.2.1.2 Charles' law......Page 260
8.2.1.5 Poisson's law......Page 261
SOLUTION......Page 262
8.2.2 Power required for air compression......Page 263
8.3 FLOW OF COMPRESSED AIR......Page 266
8.3.1 Compressed air flow in steel pipes......Page 268
8.3.1.1.1 Harris formula......Page 274
8.3.2 Compressed air flow in hose pipes......Page 275
8.3.3 Compressed air flow in pipe fittings......Page 276
8.3.4 Effect of ups and downs in the flow path......Page 278
8.3.5 Effect of curvature in the flow path......Page 279
8.3.6 Compressed air flow through nozzles......Page 280
8.4 COMPRESSORS USED ON BLASTHOLE DRILLS......Page 282
8.4.1 Sliding vane rotary compressors......Page 283
8.4.2 Rotary screw compressors......Page 285
8.4.3.1 Load/ no load control......Page 289
8.4.3.3 Load/ No load and modulation control......Page 290
8.5 MEASUREMENTS OF COMPRESSED AIR......Page 291
9.2 ROCK FRACTURE IN DRILLING......Page 294
9.2.2.1.1 Crushing......Page 296
9.2.2.1.3 Scratching......Page 297
9.2.2.3 Chemical energy......Page 298
9.3 BASIC THEORY OF SOLID FRACTURE......Page 299
9.3.1 Mohr- Coulomb theory of shear failure......Page 300
9.3.2 Griffith theory of tensile failure......Page 302
9.4.1 Penetration of an indenter......Page 305
9.4.2 Penetration of a wedge......Page 307
9.4.3 Formation fracture below a drill bit......Page 309
9.4.4 Specific energy......Page 315
9.5 DRILLABILITY OF ROCKS......Page 316
9.6.1 Protodyakonov approach......Page 317
9.6.2 Paone and Bruce approach......Page 319
9.6.3 Bauer, Calder and Workman approach......Page 321
9.6.5 Microbit test approach......Page 324
9.6.6 Indenter test approach......Page 325
10.2 WHY COMPRESSED AIR?......Page 330
10.3 SCHEMATICS OF FLUSHING......Page 331
10.3.3 Drag force......Page 332
10.3.4 Terminal velocity......Page 333
10.3.5 Laws for settlement of particles in fluid......Page 334
10.4 FORMULATION OF DESIRED BAILING VELOCITY......Page 336
10.4.1 Size of fragments......Page 337
10.4.4 Roughness of fragments......Page 339
10.4.7 Inclination of the blasthole......Page 340
10.4.8 Quantity of water injection......Page 341
10.5 FORMULATION OF COMPRESSED AIR PRESSURE......Page 343
10.5.1 Oil injection......Page 344
10.6 CHOOSING A DRILL PIPE......Page 345
10.6.2 Drill pipe surface treatment......Page 346
10.6.3 Size and shape of drill cuttings......Page 348
10.6.5 Drill pipe wall thickness......Page 349
10.7 DISCARDING A DRILL PIPE......Page 352
10.8 CHOOSING NOZZLES FOR TRICONE BITS......Page 355
10.9 CHOOSING THE RIGHT COMPRESSOR......Page 361
11.2 ATMOSPHERE......Page 362
11.2.2 Effects of humidity on atmosphere......Page 364
11.3.1 Diesel engines......Page 365
11.3.2 Electric motors and transformers......Page 368
11.3.4 Air compressors......Page 370
11.3.5 Blasthole flushing......Page 371
11.4 EFFECT OF SEVERE WEATHER......Page 373
11.4.1 Stormy winds......Page 374
11.4.5 Extreme cold weather......Page 375
12.2 DRILL OPERATION......Page 378
12.2.3 Drilling and Pipe Handling......Page 379
12.3 MODES OF BLASTHOLE DRILL COMPUTERIZATION......Page 380
12.4.1 Formation logging units......Page 383
12.4.2 Analog Drilling Recorders......Page 384
12.4.3 Electronic drilling recorders......Page 385
12.5 POSITIONING BY GPS......Page 386
12.5.2 Movement of drill by using GPS......Page 388
12.6 COMPUTERIZED DRILL SYSTEMS......Page 389
12.6.1 Measurements while drilling......Page 390
12.6.1.1.1 Time......Page 391
12.6.1.1.6 Vibrations......Page 392
12.6.1.2.2 Blastability index......Page 393
12.6.2 Automation systems......Page 394
12.7.1 System unit......Page 397
12.7.3 Input device......Page 398
12.7.4 Software......Page 399
12.8 ADVANTAGES OF DRILL COMPUTERIZATION......Page 400
12.8.1 Advantages of drilling knowledge system......Page 401
12.8.3 Advantages of GPS positioning system......Page 404
12.8.4 Advantages of integrated mining system......Page 406
12.8.5.3 Centralizer damage prevention......Page 407
12.8.5.6 Breakout wrench damage prevention......Page 408
13.2 PRIMARY REQUIREMENTS OF THE DRILL......Page 410
13.3 SIZE AND WEIGHT OF THE DRILL......Page 411
13.4 ROTARY SPEED AND TORQUE......Page 413
13.5 FEED FORCE AND SPEED......Page 418
13.7 BREAKOUT TORQUE......Page 419
13.9 GROUND LOAD BEARING......Page 420
13.11 ENGINE POWER......Page 421
14.1 INTRODUCTION......Page 424
14.2 WORKING PATTERN OF A BLASTHOLE DRILL......Page 425
14.4.1 Purchase expenditure......Page 428
14.4.3 Salvage value......Page 431
14.4.4 Calculation of owning cost......Page 432
14.4.4.2 Multiple installments......Page 433
14.5.1 Cost of maintenance and repairs......Page 434
14.5.2 Cost of consumables......Page 435
14.5.2.2 Drill lubricants......Page 436
14.5.2.4 Water......Page 438
14.5.3 Cost of accessories and bits......Page 439
14.5.3.2 Tricone bits......Page 440
14.7 TOTAL BLASTHOLE DRILLING COST......Page 441
14.9 EXAMPLE OF COST ESTIMATION......Page 442
15.2 PRE PROCUREMENT CONSIDERATIONS......Page 454
15.2.2 What type of drill?......Page 455
15.3.1 Draft of specification for the drill......Page 456
15.3.2 Erection and commissioning of the drill......Page 457
15.3.4 Operation and maintenance training......Page 458
16.2 KNOWING THE ENVIRONMENT......Page 460
16.3 MOVING THE ROTARY BLASTHOLE DRILL......Page 461
16.5 OPERATING A ROTARY BLASTHOLE DRILL......Page 463
16.7 TRANSPORTING THE DRILL......Page 466
16.10 DRILLING RECORDS......Page 467
16.11 SAFETY PRECAUTIONS......Page 469
17.2 EXPLOSION PROCESS......Page 470
17.3 FORMATION OF A CRATER BY A BLAST......Page 472
17.4 BLAST FRAGMENTATION MECHANISM......Page 474
17.4.2 Radial cracking......Page 475
17.4.3 Circumferential cracking......Page 476
17.4.6 Cracking by flexure......Page 477
17.4.8 Separation of beds......Page 479
18.2 EXPLOSIVES......Page 480
18.3.1 Velocity of detonation......Page 484
18.3.2 Detonation pressure......Page 486
18.3.4.1 Weight and bulk strength......Page 487
18.3.7 Sensitivity......Page 488
18.3.7.4 Sensitivity to detonator strength......Page 489
18.3.10 Charging density......Page 490
18.3.11 Toxic fumes......Page 491
18.3.12 Water resistance......Page 493
18.3.14 Storage life......Page 494
18.3.17 Minimum hole diameter......Page 495
19.3 REACTIONS OF EXPLOSIVE CHEMICALS......Page 498
19.3.1 Oxygen balance......Page 500
19.3.2 Volume of products of explosion......Page 502
19.3.3 Heat of explosion......Page 503
19.3.4 Strength of explosive......Page 504
20.2 BRIEF HISTORY OF EXPLOSIVES......Page 506
20.3 TYPES OF EXPLOSIVES IN A BLASTHOLE......Page 508
20.3.1 Detonator ( Blasting cap)......Page 509
20.3.4 Main explosive......Page 510
20.3.4.3 Ammonium nitrate......Page 512
20.3.4.4 Sodium Nitrate......Page 513
20.4.1 Dry blasting agents......Page 514
20.4.1.1 Poured ANFO......Page 519
20.4.2 Slurry......Page 520
20.4.2.2 Cartridged slurry......Page 521
20.4.3 Emulsions......Page 522
20.4.4.1 Granular dynamite......Page 523
20.4.4.2 Gelatin dynamite......Page 524
21.2 TESTS FOR MEASUREMENTS OF VOD......Page 528
21.2.2 Chronograph method......Page 529
21.2.5 Optical measurement method......Page 530
21.3 TESTS FOR MEASUREMENT OF STRENGTH......Page 531
21.3.4 Plate dent test......Page 532
21.3.5 Traulz lead block test......Page 533
21.3.6 Cylinder compression test......Page 534
21.4.2 Heat resistance test......Page 535
21.4.5 Friction sensitivity test......Page 537
21.5.2 Internal ignition test......Page 538
21.6.1 Critical diameter test......Page 539
21.6.4 Koenen test......Page 540
22.2 BLASTING CONSUMABLES......Page 542
22.2.1.1 Safety fuse for transmitting fire......Page 544
22.2.1.3 Detonating cord for transmitting detonation......Page 545
22.2.1.4 Detonating cord for transmitting shock......Page 546
22.2.2.1 Delay element......Page 547
22.2.2.2 Electric detonators......Page 548
22.2.2.3 Non- electric detonators......Page 551
22.2.2.4 Electronic detonators......Page 553
22.3.1.2 Blaster's ohmmeter......Page 554
22.3.2 Initiating instruments......Page 555
22.3.2.2 Electric detonation initiator......Page 556
22.3.2.4 Capacitor discharge type blast initiator......Page 557
22.3.2.7 Hercudet system initiator......Page 558
22.3.3.2 Burden measuring instrument......Page 560
22.3.3.3 Seismograph......Page 562
22.3.3.4 VOD meter......Page 563
22.4 BLASTING TOOLS AND MISCELLANEOUS ITEMS......Page 564
23.2.1 Presence of ground structure......Page 568
23.3 HAZARDS OF BLASTING PROCESS......Page 569
23.3.1.2 Faulty electric blasting circuits......Page 570
23.3.1.5 Unnoticed ground water inflow......Page 571
23.3.2.1 Nature of ground vibration waves......Page 572
23.3.2.2.1 Langefors formula......Page 574
23.3.2.2.2 Scaled distance formula......Page 575
23.3.2.3 Damage by ground vibrations......Page 576
23.3.3 Air blast......Page 580
23.3.3.1 Prediction of air blast pressure......Page 581
23.3.3.2 Damage by air blast pressure......Page 582
23.3.4 Fly rocks......Page 584
23.3.5 Air pollution......Page 585
23.3.6 Environmental changes......Page 587
24.2 ROCK SPECIMEN PROPERTIES AND BLASTING......Page 588
24.2.2 Influence of rock density on blasting......Page 589
24.3 PROPERTIES OF ROCK MASSES AND BLASTING......Page 590
24.3.2 Folds, unconformities and bedding planes......Page 591
24.3.2.2 Shooting against the dip......Page 593
24.3.2.3 Shooting along the strike......Page 594
24.4.2 Classification by index......Page 595
24.4.2.1 RQD based classification......Page 597
24.4.2.2 RMR based classification......Page 598
24.4.3 BI index based classification......Page 599
24.4.3.1 Index proposed by Hansen ( 1968)......Page 600
24.4.3.5 Index proposed by Lilly ( 1986)......Page 601
24.4.3.7 Index proposed by Gupta ( 1990)......Page 603
24.4.3.9 Index proposed by Han, Weiya and Shouvi ( 2000)......Page 604
25.2 MECHANIZED BLASTHOLE CHARGING SYSTEM......Page 606
25.2.1 Trucks for loading ANFO or heavy ANFO......Page 607
25.2.2 Trucks for loading slurry or emulsion......Page 608
25.2.3 Safety features of bulk delivery system......Page 609
25.3 BLASTHOLE CHARGING PATTERN......Page 610
25.3.1 Type and placement of primer......Page 611
25.3.2 Direction of propagation of detonation......Page 615
25.3.2.1 Top priming......Page 616
25.3.2.3 Multi point priming......Page 617
25.3.4 Air decking......Page 618
25.3.5.2 Heavy water seepage in blasthole......Page 621
25.3.5.4 Cavities in the rock mass......Page 622
25.4 DRILLING AND FIRING PATTERNS......Page 623
25.4.1 Drilling patterns......Page 624
25.4.2.1 " V" Pattern......Page 627
25.4.2.4 Channel delay pattern......Page 628
25.4.2.5 Sinking hole pattern......Page 630
26.2 BLASTHOLES IN A MINE BENCH......Page 632
26.3.1 Conventional bench blasting......Page 633
26.3.4 Presplitting......Page 634
26.3.5 Snake hole blasting......Page 636
26.4.1 Powder factor......Page 638
26.4.3 Number of free faces......Page 639
26.4.4.1 Desired rate of production......Page 640
26.4.4.4 Presence of geological structures......Page 641
26.4.5.1 Combination of shovel and dumper......Page 644
26.4.5.2 Walking dragline......Page 645
26.4.5.3 Combination of wheel loader and dumper......Page 646
26.4.6 Blasthole inclination......Page 647
26.4.7 Burden......Page 651
26.4.8 Blasthole spacing......Page 652
26.4.9 Subdrilling......Page 653
26.4.11 Size of the blast......Page 655
Pearse ( 1955)......Page 656
Langefors and Kihlstrom ( 1963)......Page 657
Lopez Jemino ( 1980)......Page 658
Konya and Walters ( 1972 and 1983)......Page 659
Burden to blasthole diameter relationship......Page 660
Stemming to burden relationship......Page 661
26.7 DESIGN OF CONVENTIONAL SURFACE BLAST......Page 662
Solution 1......Page 664
26.8.2 Snake hole blasting......Page 665
26.8.3 Cast blasting......Page 667
Example 2......Page 669
Solution 2......Page 670
Appendix 1 Properties of atmospheric airat high altitudes......Page 674
Appendix 2 Air properties at various temperatures......Page 678
Appendix 3 Bailing velocities in blasthole annulus......Page 682
Appendix 4 Air pressure loss in steel pipes......Page 686
Appendix 5 Air pressure loss in hose pipes......Page 692
Appendix 6 Air pressure loss in pipe fittings......Page 695
PLACE OF TUNGSTEN CARBIDE IN SUPERHARD MATERIALS......Page 701
GENERAL INFORMATION ON TUNGSTEN CARBIDE......Page 702
MANUFACTURE OF TUNGSTEN CARBIDE INSERTS......Page 703
Sintering......Page 704
Grinding......Page 705
TUNGSTEN CARBIDE INSERTS FOR DRILLING BITS......Page 706
Appendix 8 Scales of hardness – Measurements and their conversion......Page 708
Appendix 9 Manufacturers of rotary blasthole drilling equipment......Page 712
Appendix 10 Details of rotary blasthole drills manufactured all over the world......Page 720
Appendix 11 Details of drill pipes used for rotary blasthole drilling......Page 726
Appendix 12 Details of stabilizers and other miscellaneous items......Page 732
Appendix 13 Details of shock absorbers......Page 740
Appendix 14 Properties of some rocks......Page 742
Appendix 15 Bibliography......Page 750
Index......Page 770