PELEDAKAN TAMBANG TERBUKA

Disajikan dalam :RAKER INTERNAL PT. BUMA

(11 - 12 Oktober 2004)

oleh :DEDY IRAWAN

DIVISI TAMBANG UMUMPT. DAHANA (PERSERO)

S A M A R I N D AKALIMANTAN TIMUR 2 0 0 4

MATERI PEMBORAN DAN PELEDAKAN

TEKNIK PELEDAKAN

TEKNIK PEMBORAN

EKONOMI PELEDAKAN

DAMPAK PELEDAKAN

SAFE BLASTING

MAJOR FACTORS INFLUENCING BLAST EFFICIENCYMAJOR FACTORS INFLUENCING BLAST EFFICIENCY

ATTITUDE

COMMUNICATION

BLAST DESIGN

GEOLOGICAL EFFECTS

ATTITUDE PAYING ATTENTION TO DETAILS

EACH OPERATION MUST BE COMPLETED AS PRECISELY AS POSSIBLE

TOTAL QUALITY MANAGEMENT (T.Q.M)

GROUP EFFORT

COMMUNICATIONCOMMUNICATION) SAFE BLASTING PRACTICES REQUIRE GOOD COMMUNICATION.

) COMMUNICATION BETWEEN MEMBERS OF SAME GROUP AND BETWEEN GROUPS.

) OPTIMUM BLAST DESIGNS DEPEND ON INPUT FROM EACH GROUP.

KEYS TO EFFICIENT BLAST KEYS TO EFFICIENT BLAST DESIGNDESIGN

UNIFORM ENERGY DISTRIBUTIONUNIFORM ENERGY DISTRIBUTION

APPROPRIATE ENERGY APPROPRIATE ENERGY

CONFINEMENTCONFINEMENT

PROPER ENERGY LEVELPROPER ENERGY LEVEL

ADJUSMENT OF DESIGN TO MEET -ADJUSMENT OF DESIGN TO MEET -

EXISTING CONDITIONSEXISTING CONDITIONS

APPROACH TO ACHIEVING OPTIMUMAPPROACH TO ACHIEVING OPTIMUMBLAST EFFIENCYBLAST EFFIENCY

BlastDesign

DesignRefinement

BenchPreparation

PerformanceEvaluation

PatternLayout

 Firing Drilling

BlastLoading

Optimum BlastOptimum BlastPerformancePerformance

O PTIM UMEXPLO SIVES

PERFO RM ANC EEXPLO SIVES EN ERG Y LEVEL

GEOLOGICAL EFFECTS  Blasting results are influenced more by rock properties than explosive properties.

Rock properties:Compressive strength >> Tensile strength

  Rock Structure: Rock fragmentation is primarily controlled

by bedding, jointing, and faulting. Smaller drill pattern minimize the adverse effects of bedding and

fractures but increase drill and blast costs.

Explosives with high gas production (ANFO) are appropriate for highly jointed or fractured rock.

The orientation of the free face to the joints sets is also a key consideration for fragmentation and wall control. 

W a t e r Static water Dynamic water Multiple priming is advised in wet blast hole

GEOLOGICAL EFFECTS

Dipping seams of factures into pit: unstable walls excessive backbreak

Dipping seams into rockmass: unbroken toe overhang potential

Joints parallel to free face: good wall control can be best orientation

Joints angled to free face: blocky face excessive end break

Simplified blocky rockmass  poor

fragmentationfree face zone

         

 expanded pattern prevents even energy distribution

  

uniformfragmentation

        

   tight pattern promotes even energy distribution

bench Spacing should be reduced

Presplit EvaluationPresplit Evaluation open pitopen pit

open pitopen pit

bench Spacing can be expanded

EXPLOSIVESEXPLOSIVES   Hard massive rock – High density explosive  Soft / Fractured rock – Low density explosive

  Explosive with high gas production (such as ANFO) for D isplacement are appropriate for highly jointed or fractured rock.  Water resistance  Chemical stability  Fume characteristics  Bulk ANFO :

Zero Oxygen Balance = 94.3% AN + 5.7% FO Over fuel mix, example: 92% AN + 8% FO Prod. 6% less energy CO Under fuel mix, example: 96% AN + 4% FO Prod. 18% less energy NO2 Increase sensitivity It’s generally better to over fuel ANFO rather than under fuel it.

 P r i m e r s :

Primer diameter should closely match hole dia. Two primers are recommended for blasthole over 15 meters deep [ANFO] & 10 meters deep [Emulsion Blend].

  

 

 BASIC DRILL / BLAST DESIGNBASIC DRILL / BLAST DESIGN   

BENCH HEIGHTBENCH HEIGHT

BLASTHOLE DIAMETERBLASTHOLE DIAMETER

BURDENBURDEN

BURDEN STIFFNESS RATIOBURDEN STIFFNESS RATIO

SPACINGSPACING

SUBDRILLINGSUBDRILLING

STEMMINGSTEMMING

DECKING / AIR DECKINGDECKING / AIR DECKING

ANGLE DRILLINGANGLE DRILLING

TIMING DESIGN / DELAYTIMING DESIGN / DELAY   

SURFACE BLASTING GEOMETRY

 BENCH HEIGHTIf the height is not predetermined :

BH (m) >> Blasthole Dia. (mm) / 15

BLASTHOLE DIAMETERTo achieve excellent energy distribution :

DIA (mm) = Bench Height (m) x 8

If charge diameter is less than the blast hole diameter, the “decoupling effect” must be taken into account.As blasthole diameters increase the cost of drilling, loading & explosive generally decrease.Smaller blast holes distribute the explosive energy better than large blast holes.

BURDENBurden (m) are normally equal the charge diameter (mm) x (20 – 35).Initial Burden Estimation Guide (see table)

BURDEN STIFFNESS RATIO

Equal to the Bench height divided by burden<< 2 : stiff and poor fragmentation.2 – 3.5 : good fragmentation.>> 3.5 : excellent fragmentation.

BSR can be improved by using smaller hole diameter or greater bench height.

  

 

 

 

 

 

  

 

  

 

Decoupling Effect on Detonation Pressure

% reduction in wet Diameter of ExplosiveBlastholes equals Diameter of Blasthole

% reduction in dry Diameter of ExplosiveBlastholes equals Diameter of Blasthole

Example : the detonation pressure of a 127 mm diameter explosive in a 165 mm diameter blasthole will be reduced by 38% in a wet hole and 49% in a dry hole.

Initial Burden Dimension

Explosive Density x 2 + 1.8 x Explosive Diameter

Rock Density 84

= 1-

= 1-

1.8

2.6

Burden (m) =

SPACINGNormally ranges from (1 to 1.8) x BurdenOptimum energy distribution:S = 1.15 x BPattern is laid out in “Staggered”

SUBDRILLINGNormally ranges from ( 0.3 to 0.5 ) x Burdenor ranges from (8 – 12) x Hole diameterto much Sub drilling produces “ExcessiveGround Vibration”Less Sub drilling produces “Excessive toe”To improve fragmentation the blast hole primershould be placed at grade level.

DECKING / AIR DECKINGMinimum decking for dry holes:Deck = hole diameter x 6Minimum decking for wet holes:Deck = hole diameter x 12Air decking can reduce the amount of explosivesto achieve good results by efficiently utilising the available explosive energy.

UNIFORM ENERGY DISTRIBUTION       Square Square, Staggered

Pattern Pattern            

S = B S = B  

Slighty Rectangular RectangularStaggered Pattern Staggered Pattern

    

   

S = B x 1.15 S = B x 1.5

Decking AlternativesDry Hole Wet Hole Air Deck

Deck = hole diameter x 6 deck = hole diameter x 12

Stemming

Explosives

Deck

Explosives

Stemming

Explosives

Deck

Explosives

Stemming

Plug

Air Deck

Explosives

S T E M M I N GNormally ranges from (20 to 30) x Hole dia.or equal to 0.7 x Burden.

Crushed rock confine explosive energyBetter than drill cuttings.

Wet blast holes require more stemming forconfinement than dry blast holes.

Relative Confinement (RC):>> 1.4 : Confine<< 1.4 : Fly rock & stemming ejection

Vertical Energy Distribution (VED):Charge length divided by Bench height>> 80% to produce uniformfragmentation

To improve VED : Reduce charge dia. orIncrease Bench height. Then recalculateBurden and stemming dimensions.

To calculate the relative confinement find the value that represents the stem length and charge diameter. Next

divide the value by the absolute bulk strenght of the explosives. For example, with a charge diameter of 150 mm

and a stem length of 4 m the corresponding value = 6200. Assuming that ANFO with an ABS of 3200 is the

explosives used, the relative cinfinement will equal 6200 divided by by 3200 or 1.94. Generally if the relative confinement is greater than 1.4 the cinfinement will be adequate if the value is less than 1.4 flyrock and steming

ejection may occur.

RELATIVE STEMMING CONFINEMENT CALCULATION Charge Diameter (mm)

50 60 70 80 90 100 125 150 175 200 225 250 275 300 325 3501.00 4,800 4,100 3,600 3,225 2,933 2,700 2,280 2,000 1,800 1,650 1,533 1,440 1,364 1,300 1,246 1,200 1.25 5,850 4,975 4,350 3,881 3,517 3,225 2,700 2,350 2,100 1,913 1,767 1,650 1,555 1,475 1,408 1,350 1.50 6,900 5,850 5,100 4,538 4,100 3,750 3,120 2,700 2,400 2,175 2,000 1,860 1,745 1,650 1,569 1,500 1.75 7,950 6,725 5,850 5,194 4,683 4,275 3,540 3,050 2,700 2,438 2,233 2,070 1,936 1,825 1,731 1,650 2.00 9,000 7,600 6,600 5,850 5,267 4,800 3,960 3,400 3,000 2,700 2,467 2,280 2,127 2,000 1,892 1,800 2.25 10,050 8,475 7,350 6,506 5,850 5,325 4,380 3,750 3,300 2,963 2,700 2,490 2,318 2,175 2,054 1,950 2.50 11,100 9,350 8,100 7,163 6,433 5,850 4,800 4,100 3,600 3,225 2,933 2,700 2,509 2,350 2,215 2,100 2.75 12,150 10,225 8,850 7,819 7,017 6,375 5,220 4,450 3,900 3,488 3,167 2,910 2,700 2,525 2,377 2,250 3.00 13,200 11,100 9,600 8,475 7,600 6,900 5,640 4,800 4,200 3,750 3,400 3,120 2,891 2,700 2,538 2,400 3.25 14,250 11,975 10,350 9,131 8,183 7,425 6,060 5,150 4,500 4,013 3,633 3,330 3,082 2,875 2,700 2,550 3.50 15,300 12,850 11,100 9,788 8,767 7,950 6,480 5,500 4,800 4,275 3,867 3,540 3,273 3,050 2,862 2,700 3.75 16,350 13,725 11,850 10,444 9,350 8,475 6,900 5,850 5,100 4,538 4,100 3,750 3,464 3,225 3,023 2,850 4.00 17,400 14,600 12,600 11,100 9,933 9,000 7,320 6,200 5,400 4,800 4,333 3,960 3,655 3,400 3,185 3,000 4.25 18,450 15,475 13,350 11,756 10,517 9,525 7,740 6,550 5,700 5,063 4,567 4,170 3,845 3,575 3,346 3,150 4.75 20,550 17,225 14,850 13,069 11,683 10,575 8,580 7,250 6,300 5,588 5,033 4,590 4,227 3,925 3,669 3,450 5.00 21,600 18,100 15,600 13,725 12,267 11,100 9,000 7,600 6,600 5,850 5,267 4,800 4,418 4,100 3,831 3,600 5.50 23,700 19,850 17,100 15,038 13,433 12,150 9,840 8,300 7,200 6,375 5,733 5,220 4,800 4,450 4,154 3,900 6.00 25,800 21,600 18,600 16,350 14,600 13,200 10,680 9,000 7,800 6,900 6,200 5,640 5,182 4,800 4,477 4,200 6.50 27,900 23,350 20,100 17,663 15,767 14,250 11,520 9,700 8,400 7,425 6,667 6,060 5,564 5,150 4,800 4,500 7.00 30,000 25,100 21,600 18,975 16,933 15,300 12,360 10,400 9,000 7,950 7,133 6,480 5,945 5,500 5,123 4,800 7.50 32,100 26,850 23,100 20,288 18,100 16,350 13,200 11,100 9,600 8,475 7,600 6,900 6,327 5,850 5,446 5,100 8.00 34,200 28,600 24,600 21,600 19,267 17,400 14,040 11,800 10,200 9,000 8,067 7,320 6,709 6,200 5,769 5,400 8.50 36,300 30,350 26,100 22,913 20,433 18,450 14,880 12,500 10,800 9,525 8,533 7,740 7,091 6,550 6,092 5,700 9.00 38,400 32,100 27,600 24,225 21,600 19,500 15,720 13,200 11,400 10,050 9,000 8,160 7,473 6,900 6,415 6,000 9.50 40,500 33,850 29,100 25,538 22,767 20,550 16,560 13,900 12,000 10,575 9,467 8,580 7,855 7,250 6,738 6,300

10.00 42,600 35,600 30,600 26,850 23,933 21,600 17,400 14,600 12,600 11,100 9,933 9,000 8,236 7,600 7,062 6,600 10.50 44,700 37,350 32,100 28,163 25,100 22,650 18,240 15,300 13,200 11,625 10,400 9,420 8,618 7,950 7,385 6,900 11.00 46,800 39,100 33,600 29,475 26,267 23,700 19,080 16,000 13,800 12,150 10,867 9,840 9,000 8,300 7,708 7,200 11.50 48,900 40,850 35,100 30,788

Ste

m L

eng

th (

m)

StemLength

ChargeDiameter

BASIC BLAST DESIGN      

Relative Confinement (RC)Calculation

(Stem Length x 210,000) + (Charge Diameter x 600)

RC = (Charge Energy ABS x Charge Diameter)

  Example 1 :Charge Diameter 152 mm

Charge Energy ABS 3167 j/ccStemming Length 3.7 m

Relative Confinement 1.80typically well confined

 Example 2 :Charge Diameter 152 mm

Charge Energy ABS 3167 j/gStemming Length 2.1 m

 Relative Confinement 1.11poorly confined

 Explosives Absolute Bulk Strength Calculation

Explosives Density (g/cc)

0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 1.05 1.1 1.15 1.2 1.25 1.3 1.35

2,500 1,500 1,625 1,750 1,875 2,000 2,125 2,250 2,375 2,500 2,625 2,750 2,875 3,000 3,125 3,250 3,375

2,550 1,530 1,658 1,785 1,913 2,040 2,168 2,295 2,423 2,550 2,678 2,805 2,933 3,060 3,188 3,315 3,443

2,600 1,560 1,690 1,820 1,950 2,080 2,210 2,340 2,470 2,600 2,730 2,860 2,990 3,120 3,250 3,380 3,510

2,650 1,590 1,723 1,855 1,988 2,120 2,253 2,385 2,518 2,650 2,783 2,915 3,048 3,180 3,313 3,445 3,578

2,700 1,620 1,755 1,890 2,025 2,160 2,295 2,430 2,565 2,700 2,835 2,970 3,105 3,240 3,375 3,510 3,645

2,750 1,650 1,788 1,925 2,063 2,200 2,338 2,475 2,613 2,750 2,888 3,025 3,163 3,300 3,438 3,575 3,713

2,800 1,680 1,820 1,960 2,100 2,240 2,380 2,520 2,660 2,800 2,940 3,080 3,220 3,360 3,500 3,640 3,780

2,850 1,710 1,853 1,995 2,138 2,280 2,423 2,565 2,708 2,850 2,993 3,135 3,278 3,420 3,563 3,705 3,848

2,900 1,740 1,885 2,030 2,175 2,320 2,465 2,610 2,755 2,900 3,045 3,190 3,335 3,480 3,625 3,770 3,915

2,950 1,770 1,918 2,065 2,213 2,360 2,508 2,655 2,803 2,950 3,098 3,245 3,393 3,540 3,688 3,835 3,983

3,000 1,800 1,950 2,100 2,250 2,400 2,550 2,700 2,850 3,000 3,150 3,300 3,450 3,600 3,750 3,900 4,050

3,100 1,860 2,015 2,170 2,325 2,480 2,635 2,790 2,945 3,100 3,255 3,410 3,565 3,720 3,875 4,030 4,185

3,200 1,920 2,080 2,240 2,400 2,560 2,720 2,880 3,040 3,200 3,360 3,520 3,680 3,840 4,000 4,160 4,320

3,300 1,980 2,145 2,310 2,475 2,640 2,805 2,970 3,135 3,300 3,465 3,630 3,795 3,960 4,125 4,290 4,455

3,400 2,040 2,210 2,380 2,550 2,720 2,890 3,060 3,230 3,400 3,570 3,740 3,910 4,080 4,250 4,420 4,590

3,500 2,100 2,275 2,450 2,625 2,800 2,975 3,150 3,325 3,500 3,675 3,850 4,025 4,200 4,375 4,550 4,725

3,600 2,160 2,340 2,520 2,700 2,880 3,060 3,240 3,420 3,600 3,780 3,960 4,140 4,320 4,500 4,680 4,860

3,700 2,220 2,405 2,590 2,775 2,960 3,145 3,330 3,515 3,700 3,885 4,070 4,255 4,440 4,625 4,810 4,995

3,800 2,280 2,470 2,660 2,850 3,040 3,230 3,420 3,610 3,800 3,990 4,180 4,370 4,560 4,750 4,940 5,130

3,900 2,340 2,535 2,730 2,925 3,120 3,315 3,510 3,705 3,900 4,095 4,290 4,485 4,680 4,875 5,070 5,265

4,000 2,400 2,600 2,800 3,000 3,200 3,400 3,600 3,800 4,000 4,200 4,400 4,600 4,800 5,000 5,200 5,400

4,150 2,490 2,698 2,905 3,113 3,320 3,528 3,735 3,943 4,150 4,358 4,565 4,773 4,980 5,188 5,395 5,603

4,300 2,580 2,795 3,010 3,225 3,440 3,655 3,870 4,085 4,300 4,515 4,730 4,945 5,160 5,375 5,590 5,805

4,450 2,670 2,893 3,115 3,338 3,560 3,783 4,005 4,228 4,450 4,673 4,895 5,118 5,340 5,563 5,785 6,008

4,600 2,760 2,990 3,220 3,450 3,680 3,910 4,140 4,370 4,600 4,830 5,060 5,290 5,520 5,750 5,980 6,210

4,750 2,850 3,088 3,325 3,563 3,800 4,038 4,275 4,513 4,750 4,988 5,225 5,463 5,700 5,938 6,175 6,413

4,900 2,940 3,185 3,430 3,675 3,920 4,165 4,410 4,655 4,900 5,145 5,390 5,635 5,880 6,125 6,370 6,615

Efficient Blasting Techniques - Dyno Wesfarmers - Blast Dynamics © 1995Basic Blast Design - Page 7

AW

S

(kl/g

)

Bench Height 10 mCharge Diameter 311 mBurden 10 mStiffness Ratio 1Stemming 7 mVert. Energy Dist. 30%

Bench Height 10 mCharge Diameter 145 mBurden 5 mStiffness Ratio 2Stemming 3.5 mVert. Energy Dist. 65%

Bench Height 10 mCharge Diameter 92 mBurden 3.3 mStiffness Ratio 3Stemming 2.3 mVert. Energy Dist. 77% Note : the energy factor isthe same for each example

      

1     

Poor Energy Distribution       

2    

Fair Energy Distribution    

  3     

Good Energy Distribution

ENERGY DISTRIBUTION

  Step #2Place small explosives deck in hard zone. If downhole delays are used the deck should be fired 25 ms before the main charge.

Cap Rock

  Step #3Drill satellite holes between production holes and if possible load into hard zone.

          reduce

Step #1Increase charge length while maintaining explosives confinement and or reduce the pattern size.

STEPS TO IMPROVE TOP BREAKAGE

incr

ease

Cap Rock

Cap Rock

ANGLE DRILLINGADVANTAGES>> Better energy distribution>> Reduced over break>> Better floor control>> Improve high wall stability

DISADVANTAGES>> Requires attention to drill set-up>> Generally shorter bit life>> Greater hole deviation>> Higher drilling cost per meter>> Require expert drillers>> Require wider drill benches

Normally : 10 – 18 Degree

Requires “Profiling Technique” for fresh wall.

ADVANTAGES OF ANGLE DRILLING

  POORFRAGMENTATION    USEFUL ENERGY 

   WASTED ENERGY

POOR FRAGMENTATION

Potential For Flyrock Potential For Boulder

IMPROPER DRILLING

CORRECT DRILLING

HOLE DEVIATION ON MINING OPERATION

MINING OPERATIONSMINING OPERATIONS EXAMPLES OF EFFECTS OF

HOLE DEVIATIONS

EXAMPLES OF EFFECTS OF

HOLE DEVIATIONSExtra drilling, rods, bits, coupling, man-hours and delay.Extra drilling, rods, bits, coupling, man-hours and delay.

Extra explosives, man-hours and delay.Extra explosives, man-hours and delay.

Build-ups, hang-ups, poor fragmentation, ore loss, hoh dilution and pillar weakening.Build-ups, hang-ups, poor fragmentation, ore loss, hoh dilution and pillar weakening.

Handling of unwanted rock material, accelerated wear of loaders, conveyors etc., choking of ore passes, grizzley work, chute boxes runaways and haulage spillage.

Handling of unwanted rock material, accelerated wear of loaders, conveyors etc., choking of ore passes, grizzley work, chute boxes runaways and haulage spillage.

Extra support, extra drilling for support and man-hour.Extra support, extra drilling for support and man-hour.

Accelerated wear of crushers, extra crushing and delays.Accelerated wear of crushers, extra crushing and delays.

Extra hoisting and delaysExtra hoisting and delays

Extra grinding/milling and loss of metalExtra grinding/milling and loss of metal

Total CostsTotal Costs

DrillingDrilling

ChargingCharging

BlastingBlasting

Rock SupportRock Support

Mucking/Lashing, Loading and

Transportation

Mucking/Lashing, Loading and

Transportation

CrushingCrushing

HoistingHoisting

Mineral DressingMineral Dressing

Planned OperationalPlanned Operational Extra Operational CostsExtra Operational Costs

TIMING DESIGN / DELAY   PURPOSE 

The blast’s performance will be reduced if the explosive has too little or too much delay time.

Reduce ground vibration. Delay sequencing will not overcome improper blast design

(confinement, energy distribution large toe, etc.). 

FRAGMENTATION REQUIRED

Optimum fragmentation in massive rock occurs when one hole is detonated per delay and the the delay between holes in a row is – 40 ms.

The delay between rows should be at least 2 to 3 times the delay between holes in a row. 

MUCKPILE DISPLACEMENT

Short delay intervals (<25 ms) between holes in a row reduce fragmentation but improve displacement. Longer delay intervals (> 100 ms) are required between rows to maximize displacement. The type of excavator will often determine the degree of displacement required which will dictate the delay interval between rows of blast holes.

WALL CONTROL  To short of delay intervals between holes in a row and between rows can cause excessive over break. If the delay between blast holes in the back row is less than 42 ms, the charges can act together to damage the back wall. Too short of delay interval between rows (<35 ms) can promote back break due to over confinement.

TIMING DESIGN / DELAY (cont.)

BASIC TIMING DESIGN

Select the time between holes in a row based on one third to one half the

time between rows. Delay intervals between holes in a row less than 3 ms per meter of

spacing are not recommended due to air blast and fragmentationconsiderations.

Delay intervals between rows less than 6 ms per of burden can causestemming ejection, fly rock, and excessive back break.

Multiple row blast (> 4 rows) use longer intervals in back rows. Bottom delay has generally the shortest delay and delay between

decks inthe same hole should range 10 to 50 ms (For Deck Loading).

Range Of Delay Intervals Between Rows General Consideration

Massive Structure

Blocky Structure

Highly Jointed Structure

Weak Seams, Slip Planes

Water Filled Blastholes

Explosives Density > 1.3

Compact Muckpile

Loose Muckpile

Spread Out Muckpile

Improved Fragmentation

Limit Back Break

Control Flyrock

Minimize Airblast

Minimize Ground Vibration

0 3 6 9 12 15 18 21 24 27 30 33 36

Delay Interval (milliseconds per metre of burden)

Blast Timing andDesign Configuration

O p tim umDe la y

Se q ue nc e 

Simplicity

 

Cost

Site Sensitivity

 

Fragmentation

MuckpileDisplaceme

nt

WallControl

WaterConditions

ExplosivesUsed

 

Geology

 

Safety

Row by Row Pattern

Delay configuration (ms timing shown)

PI

Nominal firing times

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

100 100 100 100 100 100 100 100

100 100 100 100 100 100 100 100

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙200 209 218 227 236 245 254 263

100 109 118 127 136 145 154 163

0 9 18 27 36 45 54 63

9 9 9 9 9 9 9

Echelon Pattern

Delay configuration (ms timing shown)

PI

Nominal firing times

42 42 42 42 42 42 42

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙102 144 186 228 270 312 354 396

51 93 135 177 219 261 303 345

0 42 84 126 168 210 252 294

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

9 9 9 9 9 9 9

9 9 9 9 9 9 9

42

42

Zig Zag Pattern

Delay configuration (ms timing shown)

PI

Nominal firing times

17

17

17

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙219 202 185 168 210 227 244 261

135 118 101 84 126 143 160 177

52 34 17 0 42 59 76 92

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

17

17

17

17

17

17

42

42

42

42

42

17

17

17

17

17

17

17

17

17

Diamond Pattern

Delay configuration (ms timing shown)

Nominal firing times

25 25 25 25 17 17 17

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙219 202 185 168 210 227 244 261

100 75 50 25 0 17 34 51

167 142 117 92 67 76 93 110

∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙ ∙

42 42 42 42 42 42

42 42 42 42 42 42

25

25 17

17

PI

PT. TRUMIX BETON BLASTING PLAN - BENCH : 7QUARRY DIVISION NONEL FIRING SYSTEMDRILL & BLAST SECTION scale 1 : 200

BENCH-6 BLASTING MACHINE

ELECTRIC DETONATOR

BENCH-7

Note : Trunk Line Delay 17 ms - 6 meters

Trunk Line Delay 65 ms - 6 meters

Crest

Toe

Drill Holes

PLAN ACTUAL PLAN ACTUAL ITEMS PLAN ACTUALDiameter (inches) 4 4 Angle (degree) 10 10 Inhole Delay No.7 30 30 Fragmentation : GoodSpacing (meters) 5.3 5.3 Digable Volume (BCMs) 15,526 15,526 Inhole Delay No.8 15 15 Displacement : GoodBurden (meters) 4.2 4.2 ANFO (Kgs) 4,025 3,950 Trunk Line Delay 17 ms 15 15 Complaint - Fly Rock : -No of Holes 45 45 Pow ergel Magnum (Kgs) 45 80 Trunk Line Delay 65 ms 29 29 - Ground Vibration : -Depth (meters) see table see table Pow der Factor (Kg/BCM) 0.262 0.260 Electric Detonator 2 2 : Other : Back Break behind C1-C3Sub-drill (meters) 1.5 1.5 Date : Approved by :

ITEM ITEMS EVALUATION

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