1st Edition

Rotary Drilling and Blasting in Large Surface Mines

By Bhalchandra V. Gokhale Copyright 2011
    782 Pages
    by CRC Press

    748 Pages
    by CRC Press

    In large surface mining operations, drilling and blasting activities constitute more than 15% of the total costs. In order to optimize performance and minimize costs, a thorough knowledge of drill and blast operations is, therefore, extremely important.

    In this unique reference volume, rotary blasthole drilling and surface blasting, as applied in large surface mines, are comprehensively covered. Both new and classic concepts, techniques and methodologies are presented, supported by numerous illustrations and practical data. In 26 chapters, drilling, surface blasting, rock, rock mass, machinery, tools and accessories, compressors and air flushing, computing and practice are many other relevant subjects are treated; the first 16 chapters deal with rotary blasthole drilling, and the 10 next chapters with the concepts, theory and practice of blasting. Moreover, the 14 appendices provide vital technical and commercial data, to further support the reader to design, plan, execute, and calculate blasthole drilling operations.

    This volume is intended for professionals and technicians in mining, exploration, geological and mechanical engineering, who are involved with the design, planning, and execution of rotary drilling and blasting operations in surface mines.

    1 Surface Rock Excavation Scenario
    1.1 Introduction
    1.2 Need for Surface Rock Excavation
    1.4 Drill and Blast Operations
    1.5 Options to Drill and Blast
    1.6 Oilwell Drilling

    2 An Overview of Blasthole Drilling
    2.1 Introduction
    2.2 Basic Concepts of Drilling
    2.3 Peculiarities of Blasthole Drilling
    2.4 Comparison of Drilling Methods
    2.5 Choice of a Blasthole Drilling Method

    3 Properties of Rocks
    3.1 Introduction
    3.2 Earth and Its Interior
    3.3 Geological Cycle
    3.4 Formation of Rock Mass
    3.5 Soils, Rocks and Their Profile
    3.6 Occurrence of Minerals
    3.7 Rock Specimen Properties

    4 Brief History of Rotary Blasthole Drilling
    4.1 Introduction
    4.2 Era of Shot Hole Drilling
    4.3 Rotary Drilling
    4.4 Rotary Blasthole Drilling
    4.5 Truck Mounted Rotary Blasthole Drills

    5 Rotary Blasthole Drilling Bits
    5.1 Introduction
    5.2 Drag Bits
    5.3 Tricone Bits
    5.4 Dull Bit Analysis
    5.5 Bit Records
    5.6 Bit Failure Analysis and Remedy
    5.7 Discarding Drill Bits

    6 Rotary Blasthole Drilling Accessories
    6.1 Introduction
    6.2 Drill Pipes
    6.3 Stabilizers
    6.4 Crossover Subs
    6.5 Shock Absorbers
    6.6 Miscellaneous Accessories
    6.8 Miscellaneous Safety Items

    7 Rotary Blasthole Drills
    7.1 Introduction
    7.2 Assemblies in Rotary Blasthole Drills
    7.3 Types of Rotary Blasthole Drills
    7.4 Layouts of Rotary Blasthole Drills
    7.5 Details of Assemblies
    7.6 Extreme Cold Operation Devices
    7.7 Comparison of Types of Blasthole Drills

    8 Compressed Air and Air Compressors
    8.1 Introduction
    8.2 Compressed Air
    8.3 Flow of Compressed Air
    8.4 Compressors Used on Blasthole Drills
    8.5 Measurements of Compressed Air

    9 Mechanics of Rock Fracture Under a Drill Bit
    9.1 Introduction
    9.2 Rock Fracture in Drilling
    9.3 Basics Theory of Solid Fracture
    9.4 Fracture of Rock in Drilling
    9.5 Drillability of Rocks
    9.6 Estimation of Penetration Rate

    10 Flushing the Blasthole
    10.1 Introduction
    10.2 Why Compressed Air?
    10.3 Schematics of Flushing
    10.4 Formulation of Desired Bailing Velocity
    10.5 Formulation of Compressed Air Pressure
    10.6 Choosing a Drill Pipe
    10.7 Discarding a Drill Pipe
    10.8 Choosing Nozzles for Tricone Bits
    10.9 Choosing the Right Compressor

    11 Effect of Altitude and Severe Weather
    11.1 Introduction
    11.2 Atmosphere
    11.3 Effect of Scarce Air in Drilling
    11.4 Effect of Severe Weather

    12 Computers in Rotary Blasthole Drilling
    12.1 Introduction
    12.2 Drill Operation
    12.3 Modes of Blasthole Drill Computerization
    12.4 Drilling Knowledge Systems
    12.5 Positioning by GPS
    12.6 Computerized Drill System
    12.7 Hardware for Drill Computerization
    12.8 Advantages of Drill Computerization

    13 Concepts for Rotary Blasthole Drill Design
    13.1 Introduction
    13.2 Primary Requirements of the Drill
    13.3 Size and Weight of the Drill
    13.4 Rotary Speed and Torque
    13.5 Feed Force and Speed
    13.6 Pullout Force and Speed
    13.7 Breakout Torque
    13.8 Hydraulic Leveling Jacks
    13.9 Ground Load Bearing
    13.10 Compressor Discharge and Pressure
    13.11 Engine Power

    14 Cost Analysis of Rotary Blasthole Drilling
    14.1 Introduction
    14.2 Working Pattern of a Blasthole Drill
    14.3 Factors Related to Blasthole Drilling Cost
    14.4 Owning Cost
    14.5 Operating Cost
    14.6 Overhead Cost
    14.7 Total Blasthole Drilling Cost
    14.8 General Considerations in Cost Estimation
    14.9 Example of Cost Estimation

    15 Procurement of Rotary Blasthole Drills
    15.1 Introduction
    15.2 Pre Procurement Considerations
    15.3 Procurement Methodology

    16 Tips for Operating Rotary Blasthole Drills
    16.1 Introduction
    16.2 Knowing the Environment
    16.3 Moving the Rotary Blasthole Drill
    16.4 Setting Up the Rotary Blasthole Drill
    16.5 Operating a Rotary Blasthole Drill
    16.6 Controlling Dust Emission
    16.7 Transporting the Drill
    16.8 Maintaining Activities
    16.9 Periodical Check Ups
    16.10 Drilling Records
    16.11 Safety Precautions

    17 Mechanics of Blast Fragmentation
    17.1 Introduction
    17.2 Explosion Process
    17.3 Formation of a Crater by a Blast
    17.4 Blast Fragmentation Mechanism

    18 Properties of Explosives
    18.1 Introduction
    18.2 Explosives
    18.3 Properties of Explosives

    19 Thermochemistry of Explosives
    19.1 Introduction
    19.2 Chemical Nature of Explosives
    19.3 Reactions of Explosive Chemicals

    20 Explosives - Their History and Composition
    20.1 Introduction
    20.2 Brief History of Explosives
    20.3 Types of Explosives in a Blasthole
    20.4 Explosive Mixes Used in Mine Blasts

    21 Tests on Explosives
    21.1 Introduction
    21.2 Tests for Measurements of VOD
    21.3 Tests for Measurement of Strength
    21.4 Tests for Measurement of Sensitivity
    21.5 Tests Related to Storage of Explosive
    21.6 Miscellaneous Tests

    22 Blasting Consumable and Accessories
    22.1 Introduction
    22.2 Blasting Consumables
    22.3 Blasting Accessories
    22.4 Blasting Tools and Miscellaneous Items

    23 Hazards to and from Blasting
    23.1 Introduction
    23.2 Hazards to Blasting Process
    23.3 Hazards of Blasting Process

    24 Properties of Rock Masses
    24.1 Introduction
    24.2 Rock Specimen Properties and Blasting
    24.3 Properties of Rock Masses and Blasting

    25 Methods and Patterns of Charging Blastholes

    25.1 Introduction
    25.2 Mechanized Blasthole Charging System
    25.3 Blasthole Charging Pattern
    25.4 Drilling and Firing Patterns

    26 Design of a Surface Blast
    26.1 Introduction
    26.2 Blastholes in a Mine Bench
    26.3 Types of Blasting in Surface Mines
    26.4 What is Involved in Design of a Blast
    26.5 Calculation of Burden
    26.6 Relationship of Blasthole Parameters
    26.7 Design of Conventional Surface Blast
    26.8 Design of Other Types of Blasts

    Appendix No. Appendix Title Page Nos.
    Appendix 1 Properties of Atmospheric Air at High Altitudes
    Appendix 2 Air Properties at Various Temperatures
    Appendix 3 Bailing Velocities in Blasthole Annulus
    Appendix 4 Air Pressure Loss in Steel Pipes
    Appendix 5 Air Pressure Loss in Hose Pipes
    Appendix 6 Air Pressure Loss in Pipe Fittings
    Appendix 7 A Note on Tungsten Carbide and Other Hard Metals
    Appendix 8 Scales of Hardness - Measurements and their Conversion
    Appendix 9 Manufacturers of Rotary Blasthole Drilling Equipment
    Appendix 10 Details of Rotary Blasthole Drills Manufactured Worldwide
    Appendix 11 Details of Drill Pipes Used for Rotary Blasthole Drilling
    Appendix 12 Details of Stabilizers and Other Miscellaneous Items
    Appendix 13 Details of Shock Absorbers
    Appendix 14 Properties of Some Rocks

    Bibliography, Index

    Bibliography, Index

    Biography

    Bhalchandra V. Gokhale is an experienced professional who has worked both in practice, on mine construction and foundation works, and on the technological side of blasthole drilling equipment. Through this book, he shares his extensive knowledge of the technological aspects of drilling, mining and construction equipment and their application.