This document discusses various rock drilling methods. It defines rock drilling and lists its objectives such as exploration and production. The document then classifies and describes several drilling methods - auger drilling, reverse circulation drilling, diamond core drilling, air core drilling, jumper bar drilling, jack hammer drilling, churn drilling, direct push rig, hydraulic rotary drilling, and sonic drilling. It provides details on the working principles, advantages, and limitations of each method.

1. -BY
UMASANKAR.U
ANNAMLAI UNIVERSITY

2. 1. Definition
2. Objective of rock drilling
3. Classification of drilling
4. Brief description for each drilling
methods
5. Drilling accessories

4.  Exploration drilling for sample collected to
estimate the quality and quantity of the mineral
reserve
 Locates and defines economic mineralization
 Production drilling-in the mining cycle drilling
performed for the placement of the explosives
 To generate under earth transportations and to
allow locomotives
 In quarrying dimensions stone is freed by
cutting channeling.

5.  Auger drilling
 Reverse Circulation drilling
 Diamond core drilling
 Air core drilling
 Jumper bar drilling
 Jack hammer drilling
 Churn drilling
 Direct push rig
 Hydraulic rotary drilling
 Sonic drilling

6. Drilling is done with the “helical screw”
Hallow stem auger-softer ground
Solid fight auger-harder ground
Geo chemical sampling at un consolidated material
Portable
Cheap & fast method
Uncontaminated samples
But poor penetration

8.  It’s similar to the air core drilling
 “High pressure fluid forced down outer pipe
and returns chips to surface up inner pipe”
 Geochemical sampling in hard and soft rocks
 Samples(rock chips) of fresh rock in large amount
rock
 Moderately priced & relatively cheap
 Quick & un contaminated
 Sample will contaminate below the water table

10.  Diamond drilling utilizes “diamond impregnated
drill bits” that attached in the end of the hallow drill
rods.
 To get cylindrical core samples.
 It give whole rock sample and more geological
information.
 Un contaminated high quality samples
 It can penetrate great depth.
 But expensive and slow method and small sample
size water supply also required .

12.  Hardened steel or tungsten blades are used to
drill
 Three blades arranged around the drill bit
 The rods are hallow and contain inner tube
 That sits inside the hallow rod barrel
 Drill cuttings removed by injection of
compressed air
 Geo chemical sampling into bed rock & it
produce small chunks of cored rock
 More costly & slower than RAB method
 Minimal contamination but small sample size

14.  There are manually operate drill used for
making blast holes in stone and road material
 The drill is consist of 1 -1.5 inch in diameter
and length between 2ft to 4ft
 Percussion is given by striking the drill
manually by hammer
 The sludge removed from the hole with a
scoop periodically
 The drill made of high carbon manganese steel
bar

15.  In mechanized mining pneumatic drills are
worked by compressed air
 The principle involved is same that of
manually operate jumper bar
 A popular variation of compressed air drill is
jack hammer
 The air pressure of the drill is 800-1000 lbs per
square inch

17.  A portable drill rig using a bit fashioned on a
massive steel cylinder that is alternatively lifted
and dropped to a hole in earth and rock
 It used to drill into soft carbonate rocks of lead
and zinc in hosted regions to extract bulk
samples of ore
 A large version of churn drill is used in oil
drilling is known as cable tool drilling

19.  This technology is pushing or hammering without
rotating the drill string
 It’s not mean the drilling but it achieves the same
result –a bore hole
 It’s limited and drilling in un consolidated rock
 & very soft material
 The speed and depth of penetration dependent on
the soil type & weight of the power of rig
 It can produce a large number of high quality of
samples quickly and cheaply
 Least penetration

21.  Oil well drilling utilizes tri cone ;carbide
embedded; fixed diamond impregnated drill
bits
 “bentonite & barite” infused drilling muds to
use to lubricate ;cool & clean the drill bit and
control down hole pressure and stabilize the
wall of the borehole
 it can pollute water and also causes dangerous
fire risks
 So redundant safety systems & highly trained
personnel are required to be implemented

23.  It’s works by sending high frequency resonant
vibrations down the drill string to the drill bit
 Vibrations may also be generated within the drill
head
 The frequency generated between 50 and 120 htz
(cycle per second)
 Depend and varied by the operator
 Resonance magnifies the amplitude of the drill bit
 An internal spring system isolates these vibrational
forces from the rest of the drill rig