Day 1 Mining Methods and Ventilation Flashcards
Minimum Width w/c eart-moving eqpt can operate
Boxcut
Wedge of waste on the slope of orebody
Wedge
Index used in com profitability of different mining operations
Stripping Index
Instantaneous SR / Ore grade
Desired pH of soil
5.5 to 6.5
Number of significant figures to w/c measurements have been made
Resolution
Used to measure displacement thru boreholes
Multirod extensometer
How many components of stress in a 3D object
9
3 for ea axis
1 d stress measurement method in borehole
Flatjack
Hydraulic fracturing
2 D stress measurement in borehole
USBM gauge
3D stress measurement in borehole
CSIRO gauge
Stress that breaks majority of rock in blasting
Reflected Tensile wave
When there is a gap of air bet explosive and rock
Decoupled explosive
Tool for soft rock used by roadheaders
Drag pick
Used in TBM to cut harder rocks
Disc/Button Cutter
Failure due to discontinuities
Structural failure
What does a wedge in a timberset do
For better fit from roof to floor
Fxn of header in a timberset
So the prop can support a larger area of roof or floor
Desc Cable bolt
Two bolts connected by wire
Installed separately then wire is tensioned
Cause of Type 1 fracture
Overall stress dist
Cause of type 2 fracture
slip on pre-existing discon
Type 3 fracture cause
Local concentration of stress
Intact rock madeup of rock mass and discontinuities
Rockmass
Macroscopic features of rock such as Arrangement Position Fractures fold Faults
Structure
Void ratio =
Volume of voids/Vol of solid
Moisture content =
W-Wsolid / Wsolid
Rate w/c temp spreads thru body
Therma Diffusivity
Amount of heat transferred thru conduction
Thermal conductivity
Use in Tensile Strength test
Brazilian Test
Use for Triaxial strength test
Hoek Cell
Distance bet discontinuity surfaces
Separation
Rock classification
Predicting the load on steel arch support in tunneling
Terzaghi - Rock Load Classification
Relates Stand-up time to unsup span of rock mass
Lauffer Stand-up time Classification
Lauffer system became the basis for this
NATM
Deere’s RQD =
(total length drilled > 10 cm) / length drilled
3 parameter in Wickham’s Rock Structure Rating
A. Rock structure
B. Discontinuity Pattern
C. Groundwater Inflow
Created the RMR System
Bieniawski
Slope angle for Sands
37-45 deg
Slope angle for Massive rock
70 deg
Slope angle of Soills
30 - 40 deg
Other name for Toe Buttress
Retaining Walls
Found just above bedrock
Regolith
Alcohol in Nitric acid solution of metlas is called
Fulmates
Black powder coated with glycerin
3300 ft/sec
Combination of NG and Guncotton
Blasting Gelatin
One of its ingredient is wood pulp
Dynamite
Diff of Straight dynamites and Dynamite
Straight dynamite cont Ca/Mg Carbonate
Creates lots of CO
Alcohol subs for NG to make this
Low Freezing Dynamites
Dynamite that produces less fumes
Ammonia Dynamites
Boreholes filled with water and blasting gelatin abpplication
Geophys exploration
Blasting gelatin with AN as chief ingredient
Semi-gelatin
Dynamite with AN as chief ingredient
Low Density Dynamite
Used in quarrying
Quarry powder
Black powder that produces less smoke
Pellet powder
Compressed air at 10000psi used in coal mines
Airdox
Liquid Carbon Dioxide cjompressed at 2000 psi then detonated
Cardox
Just like Cardox but detoinated by Ammonia chloride and sodium nitrate
Hydrox
Provides high velocity shock to high explosives to initiate them
Detonators
Most common Detonator
Blasting cap
Used to initiate grp of explosives simultaneously
Delay detonators
Pushes itself into charge after ignitio
Miner’s Squib
It’s shell is ignited by an electric current
Electric Squib
Made by spinning yarn, hemp or jutearound a central core of black powder
Safety fuse
Detonating fuse that contains PETN as explosive substance
Primacord
Holes immediately below the perimeter holes at roof
Shoulder hole
Holes adjaccent to permeter holes
Easer
- Blastholes ablong bottom of developed round
- Use to create smooth floor
- Contains explosives
Lifter
Group of blastholes around one or more uncharged holes
Burn Cut
Main explosive in a detonator
Base Charge
Equivalent to detonation by detonatino velocity
Brisance
Enlargening a hole using small explosive
Springing
Chambering
Bullying
Perimeter hole fired after main charge
Cushion Blasting
Explosive with large amt of oxidizers dissolved in water droplets surr by an immiscible fuel
Emulsion
Cordlike fused with and external flame
Used to light a series of safety fuses
Ignitacord
Used to hold down flying material
Mat
Charge that det bef intended
Premature
Small porous sphere of AN that can absorb fuel oil
6%
Temporary explosive storage at blast size
Powder chest
What are Reliever
Same as Easer
Prevents accidental det of cap due to stray current
Shunt
Hole drilled slightly downward from horizontal into floor
Snake hole
Fired during main blasting but at a high delay
Smooth blasting
Shokck from first charge detonates the succeeding rounds
Propagation Blasting
Diff of Downline and Trunkline
Downline - cord down the hole
Trunkline - Connects grp of downlines
What are Boosters
Known as Primer
Provide adequiate initiaino of charge
Also known as blockholing
Pop blasting
Also known as Mudcapping
Blistering/Plastering
4 to 6 holes converging to a point
Pyramid cut
4 to 6 holes converge an vert line
V cut
Wedge cut
Like V cut but only at one side
Drag cut
OSH TLV of CO2
5000 ppm
Lower limit of Oxygen
20%
TLV of CO
50ppm
TLV of NO2
5 ppm
TLV of NO
25 ppm
TLV of SO2
5 ppm
TLV H2S
10 ppm
TLV NH3
50 ppm
From distillation of coal
Mostly Methane
Fire Damp
Mixture of CO2 and N2
From oxidation of coal
Name given to CO2 also
Black Damp
Product of fires and smoke
CO2 and NH4
Choke damp
Mixture of gasses after a fire
After damp
Any mixture of CO2 and CH4
Can be flammable
Illawarra Bottom Gas
Lethal conc of CO
White Damp
High conc. of H2S
Stinkdamp
Indicates spontaneous combustinon
Odor of Benzene
Fire Stink
CO and H
Formed from extinquishing coal fire
Flammable
Water gas
Explosive range of CH4
5-15 %
Explosive range of CO
12.5-74%
Explosive range of H2S
4-44 %
Explosive range of H2
4-74 %
Used to measure high velocity air
5-50 m/s
Pitot-static tube
for Measuring low air velocites
0.05 m/s isg
Hot Wire Anenometer
Shows air flow dist
for lower velocities
Smoke tube
Most useful air vel meas. instrument
Vane Anemometer
For very quick spot survey
Velometer
Free air axial flow fan is
Not confined
Tube axial flow fan is
Impeller is confined
Vane Axial flow fan is
Tube axial with guide vanes
Max # of blades for part fan
Solidity
Higher the solidity, the…
Higher pressure
Longer blades means
high airflow
What is a volute
Section of fan casing where air flows after leaving impeller
Other name for Regulators
System damper
Same Q, additive pressure
Series fans
Q is additive, pressure is the same
Parallel fans
Used to reduce shock loss at fans
Fan Diffuser
Best outlet to inlet ratio
4:1
AQ Diam
27 mm
BQ diam
36.5 mm
NQ diam
47.6 mm
NQ2 diam
50.5 mm
NX diam
54.7 mm
HQ diam
63.5 mm
PQ diam
85 mm
Fleet angle
1 - 1.5 deg
Wire rope for 3200 ft and over
locked-out coil
Coal mining support
Rock bolts spaced so their combined capacity is equal to deadweight of strata that may fall
Suspension
Coal mining support
Bolting only planes of weaknesses
Keying effect
Coal mining support
Rock bolts reinforce the rock that it becomes part of the support structure
UG diam holes
1-4 in
Surface Diam holes
6 - 18 in
Explosives produce toxic fumes when
fuel shortage
Stull stoping dip
45 to 50 deg
TLV of H
4 %
Grade of backfilled subsidence area for drainage
6%
Extremely close spacing of discontinuities
60-200 mm
Pit slope for gravel
30 - 37 degv
CH4 TLV
1%
