1. Idle Time and Payload Variation
Reduction Using DMAIC Approach
For
Hanson Quarry
By
Gregory Meckes
Gregory Poole Equipment Company EMSolutions Analyst
Goutham Chandramouli
Graduate Student, IMSE at NCSU
EGR 590
Statistical Engineering using DMAIC
Dr. Timothy Clapp
2. The Six Sigma Methodology
•PROJECT CHARTER
•HIGH LEVEL PROCESS MAP
•VALUE STREAM MAPPING
DEFINE
•IDENTIFY DATA TO BE COLLECTED
•MEASUREMENT SYSTEM ANALYSIS
•BASELINE DATA
MEASURE
•CAUSE AND EFFECT DIAGRAM
•GRAPHICAL ANALYSIS OF BASELINE DATA
•ROOT CAUSE SUMARY LIST
ANALYZE
•RECOMMENDATIONS FOR ROOT CAUSE
ELIMINATION
•CREATE MOCK INTERFACE FOR FUTURE ANALYSIS
AND IDENTIFICATION
IMPROVE
•SCHEDEULES FOR CALIBRATION, MAINTENANCE
•TRAINING AND DEVELOPMENT PLAN
•TRACKING AND FEEDBACK SYSTEMS
CONTROL
3. DEFINEPROJECT CHARTER
Increase Utilization and Production
BUSINESS CASE OPPORTUNITY STATEMENT
With the ability to view TPMS data (currently on one machine for this
project at the quarry) which is not being utilized to its full potential,
will expose the current production tons per hour and the cycle time
data. The goal of the project will be to increase overall productivity by
optimizing payload capacity, identify cycle time inefficiencies, and
opportunities for production increases. The current tons per hour from
the primary crusher is 39.5 tons per hour. However, the capacity of
the CAT 773E trucks is 61 tons, but due to site constraints the target
payload will be 50 tons. In addition, the machine efficiency of the truck
BDA00258 was 60% for one weeks of data that calculated on idle time
and working time.
EMSolutions will assist in maintaining the lowest cost per hour for their
machines, increase customer satisfaction and brand loyalty.
In 2014, the idle time was 12,635 idle hours, which contributes to an
unnecessary cost. Identifying idle time variation for Hanson by 10% will result
in a significant savings from fuel costs while increasing production tons per
hour. Investments in hardware to monitor 10 other machines at their other
quarry sites will multiply this savings.
With an increase competition for EMSolutions there is a need to create value
and invest in future opportunities with Hanson.
At a Hanson Crabtree site the opportunity for increasing payload from a
current 39.5 tons per hour to the maximum allowable payload for the site due
to other conditions of 50 tons will result in estimated $5 per ton sold on the
yard. Following the completion of the analyses on payload management, load-
haul cycles, and the primary crushing, recommendations will be proposed in an
effort to better match production with customer demand.
Increase Tons per Hour from 138 TPH to 225 TPH.
GOAL STATEMENT PROJECT SCOPE
Y=f(x)
Reduce idle time based on a benchmark per machine during the
payload cycle and optimize cycle time that will result in an increase in
production and lower fuel burn per unit of material moved.
Calculate the current load-haul cycle and tons per hour for efficiency,
effectiveness and cost.
Y’s: Sales, Service and Parts Increase/Decrease, Component Life
Increase/Decrease, Tons per Hour
X’s: Site Layout, Payload Management, Scales, Operator
In Scope:
Operators, Equipment, Payload Scales, VIMS, TPMS, Jaw Crusher
Out of Scope: Competition, New Site
Start: Pit Loader
Stop: Crusher
PROJECT PLAN TEAM SELECTION
Identify the payload and cycle time to identify improvements at the
quarry site.
Observations and recommendations will take place from:
February 18
th
– March 1
th
: Pick a site and install hardware if necessary
March 1
st
– April 30
th
: Collect and analyze data
May 25: Make recommendations
Quarry Manager
Greg Meckes- Gregory Poole Equipment Company EMSolutions Analyst
Goutham Chandramouli- Graduate Student, NCSU
Shane Bailey- PSSR
Process Owner: Brett Mireau (EMSolutions Manager)
4. DEFINE
• The process of generating the aggregate
includes removing overburden, developing haul
roads, drilling and blasting of earth, excavation
of material, hauling material to the primary
crusher and then crushing the raw material into
optimal sizes for the customer.
• Most of the material at Hanson Crabtree is
granite which is a hard rock deposits, which
requires explosives and the goal is to fragment
the rock to a size suitable for loading and
transporting to the plant for further processing.
• The main elements of aggregate processing are
breaking the rock into smaller sizes or fractions
(if that is required), and then separating the
rock fragments into the different size particles
required by the customer. These sizes can range
from meters, e.g. large blocks for coastal
defenses, which would not go through the
crushing process, to fractions of a millimeter
where the particles may have gone through a
multi-stage crushing process to produce the
right size (and shape) of particle. (1)
Quarry Operations
9. Operational Definition of the KPI
KPI for Production from Hanson Aggregates
• Production Rate- Goal is 450 Tons per Hour and the current TPH is 270.
• Usually measured in Tons per Hour, month and year. Production rate is the amount of raw
material hauled to the crusher that can be produced. Alternatively, the amount of time it takes to
produce one unit of a saleable rock. Primary and Secondary Crusher has the capacity to crush 450
TPH.
• Equipment Utilization- (Production Time / Plant Operating Time) * 100
• Equipment utilization is defined as the percentage of Plant Operating Time during which
equipment is in production, and production is not prevented by equipment malfunction,
operating delays, or scheduled downtimes. Idle time should be zero, but there are conditions that
require idle time.
• Operational Availability- Uptime / Operating Cycle
• Operational availability is a measure of the average availability over a period of time and it
includes all experienced sources of downtime. Where the operating cycle is the overall time
period of operation being investigated and uptime is the total time the system was functioning
during the operating cycle.
MEASURE
10. Data Sources Product Link and Truck Production
Management System (TPMS)
Truck Production Management System
Uses strut pressure sensors and on-board computing to indicate overloading or under loading
Providing payload, load time, haul time and distance, return time and distance.
Prevents premature wear by reporting on overloading, Prevents profit losses resulting from under loading
External Lamps Indicate Current Payload: Payload Green light indicates continue loading, Flashing green
indicates one more load, Red light indicates loaded
Product Link Telematics Device- reports data into VisionLink, Equipment usage, GPS location, Fuel burn, and
idle time vs. working time.
MEASURE
11. Identify areas where we can reduce the idle time defects on site during the truck cycle times. Once we
identify these areas there will be a direct correlation to an increase in production rate tons per hour.
Based on our data we will analyze the data to identify where there are areas of improvements to
maximize the equipment utilization and increase production. We will identify where idle time events
(stopped loaded time, stopped empty time) occurred, how long, impact on production and opportunities to
increase production by tons per hour. Also, idle time impacts fuel cost, maintenance costs, warranty impact,
engine, component life span and salvage value.
These trucks weren't able to differentiate idle time and working time before we installed a switch and
movement based work definitions enabled. Therefore, there was no way to measure how efficient the trucks
actually were in terms of working and idling.
Current idle time from April 8th - 26th (15 operating days) on the one truck we are monitoring shown below
Idle Time Reduction Product Link
MEASURE
12. Possible Solutions for Problem
• Idle time- Policy for amount of acceptable time to leave truck running, prevent bunching at
crusher or pit loader, Queuing, Cycle time improvements and standard operating procedures.
• Lack of Communication- Truck exchange time training, Spotting communication with loader
operator when ready to load.
• Queuing and Spotting- Training!
• Haul road conditions- Superelevation, Inconsistent grade fixed to constant, Increase Haul Road
width and Visibility, Transmission shifting points with signs on road when and what gear to shift
to, Repair ditches.
• Payload Management- Loader bucket fill factor, Total payload, Payload calibrations, Standard
operating procedures, Tailgates, Training!
MEASURE
13. Measurement System Analysis
Can’t trust the historical data from the trucks because the system hasn’t been utilized for 10
years. The original data collected was actually from another quarry before the truck moved to the Crabtree
quarry. But we have some data from the actual site and used it as a model for our recommendations for
improvement.
Currently working on validating the data for accuracy. We plan to recharge the strut pressure on
the trucks and install new strut sensors. Ensure data accuracy by charging strut pressure in cylinders and new
strut sensors. Weekly verification by performing a simple calibration. Fix the external indicator lamps for
loader operator efficiency. Green light indicates continue loading. Flashing red indicates one more load. Red
light indicates loaded.
Operators would turn the payload system off, and didn’t know that we were collecting data.
Informed operators to not turn the switch to the off position.
MEASURE
14. The 988G loader has a Spade Rock Teeth
bucket which has a 8.33 yd3 heaped and 6.9
yd3 struck capacity.
Capacities MEASURE
15. MEASURE
• KPI’s listed in adjacent table
• Sparse data available from
current site
• Target for KPI’s chosen from
best 25% of data (excluding
outliers)
• These KPI’s are for 773E Haul
Trucks and 988G loader
Identifying and Establishing Benchmarks for KPI’s
(for Lehigh Hanson Crabtree Site)
All times in minutes and distances in miles
Benchmarks
Machine BDA00258
Ideal Cycle Count 38
Target Total Payload in Tons 1900
Target Avg Payload in Tons 50.00
Operating Hours Hr 8
Target Production Tons/Hr 224.30
Cycle Rate (1/Hr) 4.25
Avg. Travel Empty Time 3.65
Avg. Stopped Empty Time 1.17
Avg. Load Time 1.67
Avg. Stopped Loaded Time 0.28
Avg. Loaded Travel Time 5.9
Avg. Cycle Time 12.60
Avg. Travel Empty Dist 0.8
Avg. Loaded Travel Distance 0.70
Avg. Cycle Distance 1.5
16. Historical Data
1. Data retrieved from TPMS
2. Data cleansed
3. Data sampled for top % for benchmarking purposes
4. Observation
MEASURE
Machine Day
Cycle
Count
Total
Payload
Avg
Payload in
Tons
Target
Total
Payload in
Tons
Target Avg
Payload in
Tons
Operating
Hours
Hr
Production
Ton/Hr
Target
Production
Tons/Hr
Lost
Production
Cycle Rate
(1/Hr)
Avg. Travel
Empty Time
Avg.
Stopped
Empty
Time
BDA002
58
4/23/20
15
34 1333.85 39.23 1700 50.00 9.6 138.94 177.08 366.15 3.54 4.00 4.04
Avg. Load Time
Avg. Stopped
Loaded Time
Avg. Loaded
Travel Time
Avg.
Cycle
Time
Avg. Travel
Empty Dist
Avg. Loaded
Travel
Distance (mi)
Avg. Cycle
Distance
Total Runtime Idle Hours
Working
Hours
Idle
Percentage
2.48 0.75 5.87 16.86 0.8 0.66 1.46 9.55 2.71 6.84 40%
17. Graphs of Weekly Production Data for 773E ( Past
data for truck- BDA00258 )
MEASURE
Avg. Stopped Empty time constitutes close
to 24% of total cycle time.
Stopped Empty time is negative
contributor to productivity!
23%
24%
15%4%
34%
Cycle Time- Components
Avg. Travel Empty Time
Avg. Stopped Empty
Time
Avg. Load Time
Avg. Stopped Loaded
Time
Avg. Loaded Travel Time
175.75
96.14
102.10
157.22
173.10 176.63
159.76
168.25
124.92
0.00
50.00
100.00
150.00
200.00
250.00
7 8 9 10 11 12 13 14 15
PayloadTPH
Hour of the Day
Production TPH
Target= 224.30 TPH
19. Cycle Time
and
Payload
Variation
Loader Operator
Truck operator
Site Condition Equipment Condition
Improper Approach Angle
Incorrect Pass Count
Fill Factor
Wrong Gear Selection
Improper Queuing
Improper Spotting
Excessive braking
Too many speed reducers
Poor maintenance
Poor base
construction
High Rolling
resistance
Tires
Improper Pressure
Worn/Damaged
Poor Maintenance
Poor Drive
Train
Poor Maintenance
Poor Lubrication
Availability and
Utilization
Grade
Consistency
Passing Room
Bench height
Pit Floor Condition
Cause and Effect Diagram for Payload and Cycle Time
Variations
ANALYZE
20. Correlation Amongst Various KPI’s
• Correlation between ‘Cycle time’ and
‘Stopped Empty Time’
• Interestingly, Cycle time has
strongest correlation (r= 0.5509) with
Stopped Empty Time which is a
negative contributor to productivity
ANALYZE
21. ANALYZE
• Regression- To check for statistical
significance and effect of various factors
over Cycle Time using regression
• Regression seems to be fitting suspiciously
to well!
• This is because, all the effects that have
been declared as statistically significant
are nothing but all the Various times that
linearly sum up to Cycle Time
• Using variations of regression too seem to
deliver similar results
• Hence Regression is not a good tool to
validate our conclusions from correlation
Regression to Find Statistical Significance of Effects on
Cycle Time
23. Queuing and Spotting
Spotting= Maneuvering the truck under the loader
to begin the loading process
Queuing= Amount of time the trucks have to wait
while another truck is loaded/dumping
• Stopped Empty Time distribution is shown
beside
• Fitting a Non-Normal Distribution (as is clearly
seen from the histogram)
• Performed capability analysis with Upper Spec
Limit of 2 minutes (Benchmark= 1.71 minutes)
• 56% of observations are above USL
• Indicates inefficient Queuing and Spotting
practices or Bottle neck of loading capacity at
the Loader
ANALYZE
Capability Analysis done
just to find the % of data
above an USL, as this is
Non-Normal data
24. Root Causes for Increased Stopped Empty Time
• Currently, the operator of the pit loader was spotting
trucks at a 70-80 degree angle that increases loading
time
• Thus the loader operator now must load the truck in
an ‘H’ pattern that increases the loading time, which
increases cycle time and causes queuing
• Although, the loader is in the correct position it is up
to the truck operator to ensure they are in the proper
location.
• The ability to differentiate the stopped empty time for
the productivity of trucks in an attempt to account for
productivity lost when the trucks queue at a loader
will come later when new hardware is installed.
However, while onsite I noticed that 2 minutes of
queuing occurred too often causing the second truck
to wait the amount of loading time for the other truck
being loaded.
ANALYZE
25. Analysis on KPI data (Past data)
ANALYZE
Capability analysis
on payload data
• A whole week’s data is
selected and analyzed
• Payload distribution is
lest skewed with mean
of 48 tons (Target=50)
• Load time distribution
is right skewed with
mean of 2 minutes
(Target=1.7 minutes)
• This shows low loading
efficiency
Capability analysis
on Load time
26. Correlation of Payload vs. Load Time and Distance
• Payload correlation with
other KPI’s such as Load
Time, Load Travel Time, and
Load Travel Distance is
studied
• Most importantly, correlation
with Payload (in tons) and
Load Time (in minutes)
• As seen before in the
distributions of Payload and
Load Time, the correlation is
also weak (r=0.0046)
• This shows that even in cases
when Load Time is high,
Payload does not seem to
increase, indicating LOSS in
Productivity
ANALYZE
27. ANALYZE
• Loaded travel distance is
constant, not considering
the few extreme values
• However loaded travel
time seems to be
exceeding USL (selected to
be 3 standard deviations
above mean) 15% of the
times
• This indicates a problem
with haul road conditions/
poor driver skill/poor truck
condition as a probable
root cause
Loaded Travel Time and Loaded Travel Distance
Comparing the
Distributions of Loaded
travel time (min) and Haul
distance (Miles)
28. Load Placement and Sideboards vs Tailgate
Currently the loader operator is loading the trucks heavily on the left side of the truck. It is vital to
get accurate information on payload data via TPMS to keep the loads at a 66%-33%
distribution, which calculates the payload by strut pressure increases.
This correlates to reduced cycle time due to transmission torque placed at less loaded areas while
hauling, machine stability, spillage causing support equipment to clean haul road, component
life impact of frame, suspension and tires.
Due to the steep grade of 20% for 1,000 feet when exiting the pit on the west ramp we have a
potential for material spilling out if the operator loads to much material to the rear. Therefore,
the operator is limited to the amount of material he can place on the trucks.
ANALYZE
29. Loader Bucket Fill Factor
The productivity of the loader is defined by the bucket size, capacity and fill factor. Also, the
loader cycle time is dependent upon the time required to fill the bucket and then transfer into the
haul truck. This is tied to the number of passes or buckets of material to fill the haul truck.
Based on the bucket size of 8.33 yd3 and material density on average of 1.5 tons yd3 the
bucket should contain 12.5 tons per pass. With a total pass count of 5 the payload transferred to
the truck should be 62.5 tons, and at a 4 pass count should achieve 50 tons. A rule of thumb is that
if the remaining truck capacity is greater than one third of the loader bucket then you should make
an additional pass. In our case, we should make 5 passes to achieve the rated payload, yet we are
not achieving the rated payload at the current pass count. Fill factors on wheel loaders are
affected by bucket penetration, breakout force, rack back angle, bucket profile and ground
engaging tools such as bucket teeth.
ANALYZE
30. Haul Road Conditions
Haul Road Conditions Variables that directly Impact Cycle Time
Rolling Resistance (RR) is a measure of the force that must be overcome to roll or pull a wheel over the
ground. It is affected by ground conditions and load — the deeper a wheel sinks into the ground, the
higher the rolling resistance. At Hanson Crabtree a 2% base resistance is used for estimating.
Grade Resistance is a measure of the force that must be overcome to move a machine over unfavorable
grades (uphill).
Steepest portion of grade is approximately 1,000 feet while loaded, the total grade is 20%, which reduces
the total payload, and the grade is very inconsistent. This is correlated to the longer loaded cycle times
and inconsistent automatic gear shifting.
Road width has an impact because we noticed that some previous cycles there were imprints of truck tires
on the berms.
Drainage issues on the haul road where there is no defined ditches.
Visibility issues that are safety concerns when the empty truck returns and enters the switchback.
ANALYZE
31. Superelevation at Switchbacks
The switchback when returning from the dump event has a turning radius is 200 feet with no
percent grade for superelevation. The fact that there is a reduced visibility in the turn makes it
difficult to maintain speed and know if it safe to enter the haul road. The switchback when
exiting the pit area and entering the haul road has a 300 foot turning radius with minimal
existing grade.
Negotiating curves can generate high lateral tire forces. These forces contribute to reduced
traveling speed, high tire wear and ply separation. Superelevating the curve helps eliminate
these forces. The amount of superelevation depends on the curve’s radius and the speed at
which it is negotiated. Superelevated curves should be maintained in good tractive conditions.
ANALYZE
32. Cycle Time: Visibility at Switchbacks
Another issue that we found onsite is the limited
visibility of the 137 Ton trucks traveling empty
on the return route to the pit loader. This
presents a safety issue, which mines are
federally regulated by MSHA, so the trucks have
to almost come to a complete stop when
entering the two way pit road at the
switchback.
This directly impacts the cycle time of these trucks
when returning to the pit loader and potential
to have to wait until the loaded truck exits the
main haul road.
Return route from crusher entering haul road
Exiting loading area entering haul road
ANALYZE
34. Solutions Identified and Validated
Payload- Increase fill factor of loader to allow additional payload per pass to reach optimal target.
Payload and Cycle Time- Install rear tailgates to allow for additional payload without spillage up
the steep haul road in order to meet production of 450 Tons per Hour and reduce the loading
cycle time by removing side boards that were added to increase payload.
Cycle Time- Haul road has a 20% grade exiting the pit and has inconsistent grade changes along
the road, so we plan to re-grade the haul road to a continuous grade.
Cycle Time- The return from dump and exiting the pit onto the beginning of haul road have
switchbacks that are not superelevated to allow for faster turns, so we plant to re-grade to have a
4% grade at top bank.
Cycle Time- Visibility issues entering the haul road from the return. We recommend installing a
stop light based system to allow trucks to know if it is safe to enter.
Cycle Time- Truck Exchange Queuing and Spotting- Ensure that the loader operator is in constant
communication with the trucks. Also, correct training and tracking the times for loading, queuing
and spotting.
IMPROVE
35. Bucket Fill Factor 988G Loader & 773E Haul Truck
Loader operator currently utilizing a 5 pass loading technique, yet based on our data we see that the
average payload is only 40 tons. Based on the data, we see that the average fill factor is around 64%, which is 8
tons per pass, so the current tons per hour production is 141 TPH. Given that we have 90% operator efficiency
and 100% availability.
With operator training we will ensure that the operator is correctly filling the bucket. Take the time to load
the first pass full. This may help if any additional passes are under-loaded. Also, we will decrease the wait to load
time by ensuring the trucks stay on their cycle by holding one truck up 2 minutes if they bunch.
Our recommendation, it to increase the bucket fill factor to 80%, which will increase to 50 tons per cycle.
The 5 cycles per hour at 50 tons would equal 225 tons per hour, which will equate to an increase of 58%.
Based on a 9 hour day, less one hour for brake, setup and maintenance time, there is a possibility to achieve 36.5
cycles in a day.
Therefore, the total production for one day would increase from 1,134 to 1794 tons produced per day,
which is a difference of 659 tons per day, 3,297 tons per week and 171,472 tons per year.
Based on an average sales price of finished product at $22, Hanson Crabtree could have an additional sales stock
inventory of $3,772,396 by increasing the payload of the trucks with tailgates, bucket fill factor and operator
training.
IMPROVE
36. Fleet Production and Cost Analysis on Fill Factor and
cycle time improvements. This will be our benchmark for
the study. This is where how will need the required KPI.
IMPROVE
37. IMPROVE: Load Placement and Sideboards vs Tailgate
Currently the loader operator is loading the trucks heavily on the left side of the truck and to the front due to road
conditions exiting the pit and high sideboards that require the loader to raise the bucket higher which increases
cycle time and loading time.
One recommendation to remove the existing sideboards, which were added to increase payload capacity, but it seems
to be working against them. The loading height of the truck with sideboards is 3971 mm and the loader has a max
lift with 45 degree dump of 4079 mm. If we remove the sideboards and decrease the loading height then we will
see a decrease in loading time, queuing time and a more efficient cycle time.
Due to the steep grade when exiting the pit we have a potential for material spilling out if the operator loads to much
material to the rear. Our recommendation is to install tailgates to increase the payload capacity, decrease the
potential for support equipment to clean debris that fall out of the truck while traveling up the steep grade, and
increase the loading time for the loader because of the height limits.
The installation of tailgates will allow for the payload to increase from 40 tons to 50 tons per haul.
• Establish a load placement pattern, first bucket back, then front, then center.
• Center load above hoist cylinders and along body centerline
• Always target 66% - 33% load split on front/rear axles.
IMPROVE
38. Haul Road Conditions
Haul Road Conditions Variables that Impact Cycle Time
Based on our analysis of the truck cycle time the average loaded travel time is 6.03 minutes. After improvements are made
to the haul road we should see a reduction of loaded travel time. The current grade going up the west bank is
approximately 20% that exceeds Cat recommendations of 12%.
This was a poor design from the beginning that the current manager has little control over. However, we can establish a
constant grade going up the haul road that should improve cycle time. Steepest portion of grade is approximately
1,000 feet while loaded, and the grade is very inconsistent. With the use of rear tailgates we will be able to haul more
material to the plant.
Recommendations related to improved haul road conditions of smooth, constant grades will:
• Minimize transmission shifts
• Maintain higher average speed
• Reduce spillage
• Reduce fuel consumption
• Allow more constant braking effort on returns
IMPROVE
39. Superelevation at Switchbacks
To reduce the return time and haul time from exiting the pit to enter the haul road, which is 200 feet and the
switchback when returning from a load is 100 feet, so we recommend super elevating the turns to maintain speed
at a 4% grade. Once, the road is fixed we should see a decrease in cycle time.
This is most important at the point when exiting the pit to maintain speed gained while exiting the pit.
• Employ superelevation to maintain consistent truck speeds
• Strive for consistent truck speed for optimal performance
• Recognize that poorly designed curves produce slower cycle times and higher overall costs
• Considers widths and clearances
Entering the haul
road (after loading)
Entering haul road
(after dumping)
IMPROVE
40. Cycle Time: Visibility at Switchbacks
This directly impacts the cycle time of these trucks when
returning to the pit loader and potential to have to wait
until the loaded truck exits the main haul road.
Our recommendation is to install sensors with a stop light at (2)
on the main haul road. At (3) the stop light shows yellow
and (4). when a truck has exited both sensors then the
stop light will show Green. When a truck is entering the
return from the crusher to the pit it will show yellow when
the truck passes (2).
Not only will this increase the safety while these heavy trucks
travel down the haul roads, but this has potential to
significantly reduce the total cycle time.
IMPROVE
41. Truck Exchange Time with Queuing and Spotting
Spotting correctly will impact the loading time and cycle time for the trucks. Some of our recommendations for the loader
are: Spot trucks close to the material—in the pocket you dug filling the last truck, if possible—at an angle that gives the
loader a tight V pattern. Tires should roll about 1½ revolutions in each direction. You want only enough travel time to
raise the bucket over the truck's sideboards and drop it back to the loading floor. Speed cycle times by setting the throttle
at high idle, the transmission in first gear, and using the neutralizer pedal. A “V” pattern loading method will reduce the
wheel revolutions and optimize the hydraulic cycle time that will decrease the loading time.
Spotting for the trucks is related to truck exchange time and will decrease the cycle time and loading time. Some of our
recommendations are: when another truck is being loaded enter the loading zone, keep the loader on your driver side
when applicable, pull up to the closest point to keep the loaded truck at a 30 degree angle and 100 feet away from it
ready to pull forward and placed into reverse to spot the loader.
Based on Caterpillar mining.cat.com site “Exchange Time is the elapsed time from when the loaded truck receives its last
pass until the next truck receives its first loading pass. Ideally, a good exchange time is 0.7 minutes, or 42 seconds. An
acceptable time would be 0.9 minutes or 54 seconds.
IMPROVE
43. Plans for Control Phase and Way Forward
• Ensure implementation of proposed
Improvements after Client agrees with
conclusions derived from support data
• Finish Calibrations of measuring
instruments
• Set-up a Calibration schedule and
integrate it with preventive maintenance
Schedule
• Begin weekly downloads and reports for
the customer
• Setup master report format and generator
to facilitate above step
• Roadblocks might come from operators
• For the site we will clarify roles and
responsibilities
• Daily Toolbox Talks with operators
• Establish metrics and personal incentives
• Regular review and updating of displayed
key metrics to align with business goals
• Display daily, weekly and monthly
performance targets in the shop
• Monitor and measure progress against
metrics
• Maintain ongoing communication and
resolution of challenges
• Open communication for feedback
• Training operators with CAT personnel
• Validate projected returns
• Horizontal Deployment to other
equipment and sites
CONTROL
