2. Dragline setup
Highwall Crest
Highwall Toe
Lowwall berm
Lowwall Crest
Lowwall Toe
Coal edge
KEY
Spoil Toe
Spoil
Cable boat
DL Cable
LV Park up
Direction of dig
DL boom radius + 30m
DL boom radius
Exclusion zone
BLOCK
TOP OF COALDe coaled
area
Call up Sign
4. Dragline Planning Process
1. It starts with Review of the recons of the previous strips considering the
below points.
• Dragline performance in the last strip – Prime, Rehandle, KPIs.
• Geological conditions – model variations with actual survey.
• Geological disturbances – faults, folds, intrusions, etc.
• Geotechnical structures – joint planes, highwall & lowwall stability,
failures, if any.
• Water management – low points, sump & pump locations.
• Drill and blast access.
• Coal access.
• Light vehicle access & cable access.
• Cable interactions.
• Dragline dig sequence.
• Spoil fit issues.
• Floor treatment – Ex. Floor blasting, Tuff push, etc
• Dragline entry and exit into the pit.
• Cast profiles.
5. Dragline Planning Process
2. Review the Geo-technical design parameters for highwall and lowwall for
angles and identify the potential areas of concerns. The general profile of
the dragline is as shown below.
TOPO Dragline designPrime
10m
10m
370
700
Presplit highwall
Highwall angle
HWC
HWT
CE LWT
LWC ST
SC
ST
370
Lowwall angle Spoil angle
SPOIL
Lowwall berm
SC
Max dump height=45m
Max dig depth=45m
Dragline horizon
HWC – Highwall Crest
HWT – Highwall Toe
CE – Coal Edge
LWT – Lowwall Toe
LWC – Lowwall Crest
ST – Spoil Toe
SC – Spoil Crest
LEGEND
6. Dragline Planning Process
2. Take the coal edge from the previous strip on floor of coal and offset it by 3m
and then normalise the line. If seam thick ness is more than 5m then reduce
the offset distance. As the seam thickness is 10m in this mine, so there is no
offset from the floor Coal edge. Hence normalise the coal edge line to get rid
of all the kinks in the line before projecting up to lowwall crest.
Coal edge line on Floor of Coal – As indicated by Survey
3m-Offset
Normalised line
without many kinks
Project this line
Project this line with Lowwall batter angle to a certain RL initially, may be 100m
high from the current coal edge RL. Then create a triangle surface (call
LW_37Batter) with these two lines to generate the Lowwall batter profile,
which will be used later to create Lowwall Toe & Crest lines.
PLAN SECTION
HWT-FloorofCoal
Coaledge-FOC
Offsetline-normalised
ProjectedtocertainRL
370
LW batter angle
Highwall Toe line on FOC- mostly taken from the medium term designs
Strip width=60m
7. Dragline Planning Process
3. Project the highwall Toe to the current Topo with the highwall batter angle. The
highwall batter angle is recommended by the Geo-tech analysis with a minimum
factor of safety 1.2. In a highly faulted areas, it is recommended to have a softwall
batter of 45 degrees rather than a presplit wall with 65 or 70 degree batter. Do the
same for endwall.
4. As the dragline exposes to top of coal so create the highwall toe line on TOC
and also take the coal edge line of the previous strip on the lowwall side from the
actual survey. Create the contours of the top of coal within this polygon.
SECTION
HWT
HWCHWC
CE
TOPO
Softwall – 450
Presplit wall – 650 to 700
CE
Previous strip
highwall
8. Dragline Planning Process
5. Offset the Coal edge line on TOC by 50m towards lowwall and create a triangle
using CE-TOC and offset line which will intersect with the lowwall batter profile
created earlier. The intersection of these two triangles will give you the lowwall toe
line.
HWC
HWT - TOC
TOC Contours
CE - TOC
CE - FOC
CE – TOC – Offset by 50m
Triangle with CE-TOC and 50m offset line
Triangle with CE-TOC and 50m offset line
Lowwall batter profile
SECTION
HWC
HWT - TOC
CE - TOC
CE - FOC
CE – TOC – Offset by 50m
Triangle with line-1 & 2 (Surface-2)
LWT Line
Intersection between Surface -1 & 2 will
give the Lowwall Toe line.
Lowwall
Toe
1 2
Section line
9. Dragline Planning Process
SECTION
HWC
HWT - TOC
CE - TOC
CE - FOC
LWT
Project the HWT-TOC line 90
degrees at a distance equal to
max dig depth of DL = 45m
Offset this line by 200m towards lowwall
Triangle surface with line-1 & 2 (Surface-2)
1 2
Intersection between Surface -1 & 2 will
give the Lowwall Crest line.
Lowwall
Crest
6. To create the lowwall crest line, project the Highwall Toe line at 90 degrees
vertical to an height equal to maximum dig depth of the dragline which is 45m in
this case and offset it by 200m towards lowwall. Generate the triangle with these
two lines and create an intersection line between this triangle and lowwall batter
profile to give you the lowwall crest line.
10. Dragline Planning Process
7. Then the remaining portion of the design process is to create the spoil.
1. Offset the lowwall crest line by 10m towards lowwall (which is the lowwall berm width,
it is different for different mines as recommended by the geo-tech analysis) which is
the spoil toe line.
2. Project this line at Spoil batter angle (which is 37 degrees – natural angle of repose,
this is also given by Geo-tech) to the maximum dump height of the dragline which is
45m in this case which gives the spoil crest line.
3. Then offset this line by 10m towards lowwall to give you the flat top of spoil &
4. Project down at 37 degrees to the topo to complete the design.
SECTION
HWC
TOPO
CE
HWT
LWC
ST
SC SC
ST
LWT
1
2
3
4
11. Sample Dragline design
HWC
HWT - TOC
CE - TOC
LWT
LWC
ST
SC
SC
ST
SOFTWALL – 450
HIGHWALL BATTER PRESPLIT WALL – 700
HIGHWALL BATTER
LOWEST
POINT
Create the triangle file from the design and find out the prime and spoil volumes
for each block to do the spoil balance.
At this stage get the Geo-tech approval of the design before start working on
sections and 3d-dig for the sequence and schedule.
12. ● The dragline horizon in this cross section can be calculated using the following
formula:
𝑆𝑝𝑜𝑖𝑙 𝐴𝑟𝑒𝑎
1.25
÷ 𝑆𝑡𝑟𝑖𝑝 𝑊𝑖𝑑𝑡ℎ = 𝐷𝑟𝑎𝑔𝑙𝑖𝑛𝑒 𝐻𝑜𝑟𝑖𝑧𝑜𝑛
Dragline horizon - Volumes
Dragline Horizon
Strip Width
Spoil Area
Pre-strip
A
B
A = Prime = Topo – Design surface (find out for each block, this is in bcm)
B = Spoil = Design surface – Topo
(find out for each block, this is in lcm. Divide by swell to convert to bcm)
13. Spoil Balance
Fill the spoil balance sheet with Prime, Spoil room, Top of coal RLs, Seam dips,
Highwall, Lowwall batters, lowwall berm width, Spoil strike lengths, etc. Which
populates the spoil fit condition in each block. Then play with the Key, elevated
and double elevated bench elevations to make the spoil to fit. Sample sheet is
shown below.
Based on the bench
elevations decide the
sequence of digging and
ramp locations between the
benches. Think of the cable
and LV access all the time.
14. Range Diagrams
Based on the spoil balance sheet, cut the sections in each block for every 100m
to find out the approximate cast volumes, dozer push volumes, dragline prime
and rehandle volumes. As this is based on the 2D plane, it is difficult to predict
the rehandles in cases like rolling the bridges and crossing the central ramps,
etc.
15. Range Diagrams
Range diagrams can be done using different software like Vulcan, Minescape,
Drag sim, etc. A sample range diagram done using Minescape is shown below.
16. 3d-dig – Dig Pack & Schedule
1. Based on spoil balance and Range diagrams adjust the lowwall crest elevations for the
design and build the new spoil from this changed lowwall crest line.
2. Export the Pre dig DTM with Pre-strip removed, dragline design, Coal seam roof & floor
into DXF format and then import all of them into 3d-dig.
3. Create the approximate blast profile in 3d-dig from the sections and blast the material
with the historical swell factor of the area and then start digging using dragline with a
dig swell of 5%.
4. Follow the sequence discussed during the spoil balance step and finish the dig.
5. Export the volumes (lcm) from 3d-dig and convert them to bcm to make a schedule with
the given dragline KPIs. Supply the schedule to the medium term scheduler.
EP07 - DL Micro Schedule 17-Mar-16
Blocks Design Extra
Volume Delay D N D N D N D N D N D N D N D
17 17 18 18 19 19 20 20 21 21 22 22 23 23 24
DL Walk in to the main pass dig2,734,192 2,734,192 0 - 1 0 0.0 17-Mar AM 17-Mar AM 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 WALK 0 0 - 1 0 1.0 1.0 17-Mar AM 17-Mar PM 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 13 KEY 82,017 82,017 2,200 9.41 1 41,387 4.0 17-Mar PM 19-Mar AM 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0
DE01 12 KEY 115,026 115,026 2,200 9.41 1 41,387 5.6 19-Mar AM 22-Mar AM 0 0 0 0 0 1 1 1 1 1 1 0 0 0 0
DE01 11 KEY 18,309 18,309 2,200 9.41 1 41,387 0.9 22-Mar AM 22-Mar PM 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0
DE01 11 KEY 119,942 119,942 2,200 9.41 1 41,387 5.8 22-Mar PM 25-Mar PM 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1
DE01 10 KEY 61,154 61,154 2,200 9.41 1 41,387 3.0 25-Mar PM 27-Mar AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 WALK - 0 0 - 1 0 1.0 1.0 27-Mar AM 27-Mar PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 13 BLKS 60,987 60,987 2,400 9.41 1 45,149 2.7 27-Mar PM 28-Mar PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 12 BLKS 115,214 115,214 2,400 9.41 1 45,149 5.1 28-Mar PM 31-Mar AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 11 BLKS 179,376 179,376 2,400 9.41 1 45,149 7.9 31-Mar AM 4-Apr AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 10 BLKS 20,205 20,205 2,400 9.41 1 45,149 0.9 4-Apr AM 4-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 9 OHAND 29,035 29,035 2,200 9.41 1 41,387 1.4 4-Apr PM 5-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 10 OHAND 64,959 64,959 2,200 9.41 1 41,387 3.1 5-Apr PM 7-Apr AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 WALK - 0 0 - 1 0 1.0 1.0 7-Apr AM 7-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 10 KEY 70,976 70,976 2,200 9.41 1 41,387 3.4 7-Apr PM 9-Apr AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 9 KEY 120,140 120,140 2,200 9.41 1 41,387 5.8 9-Apr AM 12-Apr AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 8 KEY 124,754 124,754 2,200 9.41 1 41,387 6.0 12-Apr AM 15-Apr AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 7 KEY 27,548 27,548 2,200 9.41 1 41,387 1.3 15-Apr AM 15-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 WALK - 0 0 - 1 0 1.0 1.0 15-Apr PM 16-Apr AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 10 BLKS 158,808 158,808 2,400 9.41 1 45,149 7.0 16-Apr AM 19-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 9 BLKS 175,458 175,458 2,400 9.41 1 45,149 7.8 19-Apr PM 23-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 8 BLKS 64,493 64,493 2,400 9.41 1 45,149 2.9 23-Apr PM 25-Apr AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 DELAY - 0 0 - 1 0 0.5 0.5 25-Apr AM 25-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 7 KEY 142,541 142,541 2,200 9.41 1 41,387 6.9 25-Apr PM 28-Apr PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 6 KEY 93,369 93,369 2,200 9.41 1 41,387 4.5 28-Apr PM 1-May AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 6 OHAND 8,711 8,711 2,200 9.41 1 41,387 0.4 1-May AM 1-May AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 5 OHAND 56,735 56,735 2,200 9.41 1 41,387 2.7 1-May AM 2-May PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 4 OHAND 79,089 79,089 2,200 9.41 1 41,387 3.8 2-May PM 4-May PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 DELAY - 0 0 - 1 0 0.5 0.5 4-May PM 4-May PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 4 KEY 98,412 98,412 2,200 9.41 1 41,387 4.8 4-May PM 7-May AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 5 KEY 157,313 157,313 2,200 9.41 1 41,387 7.6 7-May AM 11-May AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 6 KEY 61,187 61,187 2,200 9.41 1 41,387 3.0 11-May AM 12-May PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 WALK - 0 0 - 1 0 1.0 1.0 12-May PM 13-May AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 8 BLKS 54,428 54,428 2,400 9.41 1 45,149 2.4 13-May AM 14-May AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 7 BLKS 106,578 106,578 2,400 9.41 1 45,149 4.7 14-May AM 16-May PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 6 BLKS 150,998 150,998 2,400 9.41 1 45,149 6.7 16-May PM 20-May AM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
DE01 5 BLKS 116,430 116,430 2,400 9.41 1 45,149 5.2 20-May AM 22-May PM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
S S M
Week-12
bcm/day
Duration
(Shifts)
Start date End date
T FType
(K/T/B)
Left
Vol.(bcm)
Rate
(bcm/hr)
Op.
Hrs/Shift
# Eq.
T W
17. Wall Plan
1. Prepare a wall plan with all the information showing the plan, sections, volumes, check
list, dig sequence, faults, low spots, coal access and Sign-off. Make copies one for
machine, one for production and one for tech-services. Sample wall plan is given below.
18. Exporting the design into Titronics
1. Export the design into DXF under ACTIVE layer name.
2. Export the triangle file of the design into DXF with FINAL layer name.
3. Export other lines like block lines, text, chop line, misfires, sump location, etc into DXF
under STATIC layer name.
4. Create a long section line along highwall toe. The RL of this line should be at the lowest
RL of the design. Export this line into DXF with CENTRELINELONG layer name.
5. Create a cross section line in the centre of the design. The RL of the line should be
more than the maximum RL of the design, i.e. this line should be above the design
triangle. Export this line into DXF with CENTRELINECROSS layer name.
6. Open the Leica translator and open the ACTIVE dxf file first. Then overlay all other dxf
files on top of this. Don’t save it as dozer file, if you save it first as dozer file then all the
layers in Leica translator will be copied under one layer and if you create map file after
this then dragline doesn’t distinguish between the different layers. Hence, create a map
file first then create the dozer file.
7. When you create the map file the text becomes horizontal, which will be rectified by
editing the map file in notepad and replace the number besides “P” with the actual
angle read from the design software. The text in the map file will be saved in the last, so
edit for each text with correct text angle and then save.
8. Upload the file into IMS (Titronics) and check with the machine for both plan view and
section view.
19. Execution of the dig
1. Conduct the pre-dig meeting and discuss the plan with the operators to get
the inputs and sequence modifications.
2. Make pit tour on the first day of each crew start to explain the plan for the
week and any short term changes and sequence modifications and discuss
the alternate options to improve the performance.
3. Take lots of photos and create a diary to record all the events in the dig, which
will be useful for the next dig in the same location for better planning and
execution. Learn from the mistakes you made.
4. Involve the operators in the planning process for the next dig and plan for the
next dig while the current dig is under execution to make the plan more robust
and pool proof.
5. Communicate with the other team members about the progress and share the
experiences.
20. Things to monitor for dragline to follow
1. Do not rip into coal with dragline teeth.
2. Take assistance of dozer in cleaning the top of coal to minimise
the coal loss.
3. Do not over dig or under cut highwall outside the design limits.
4. Expose the coal edge and lowwall toe without forming the skew-
ramps at the base of the lowwall.
5. Always maintain the lowwall berm as per the design.
6. Follow the bench elevations as indicated in the dig pack.
7. Always maintain the LV access to dragline and away from it.
21. Reconciliation
1. After the dig is finished, prepare reconciliation sheet comparing the plan Vs
actuals listing
1. KPIs
2. Prime and Rehandle volumes.
3. Coal tonnes & losses.
4. Blasting data.
5. Geo-technical issues.
6. Water management issues.
7. Highwall and lowwall profiles.
8. Major delays.
2. Request drill and blast for the floor treatment, if required.