I am mining engineer with 28 years experience and am currently a Director for Mining Intelligence and Benchmarking at PwC. Opinions here are my own.
Showing posts with label dragline. Show all posts
Showing posts with label dragline. Show all posts
Monday, 3 December 2012
GBIData.com Loading Unit Full Sample Report
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rope shovel
Thursday, 29 November 2012
Wednesday, 29 August 2012
More excellent feedback from our Mine Operating Standards Best Practice Course
Best Practice Standards Series - Top 10 Mine Operating
Standards Feedback
Again really positive feedback from all participants on
Day 2, with numerous in-depth discussions generated as a result of the topics
presented.
"Very Interesting and informative"
"The Top 10 Best Practices were really
interesting"
"I will encourage other people at my mine to come to
this in the future. Would be good for maintenance people to come to this."
Achieved an overall course ranking of 4.57 out of 5. Where
1 is poor and 5 is excellent.
Ranking for Content = 4.37 out of 5.
The next Best Practice Standards Series are to be held on
the following dates at Colorado School of Mines, Golden, CO 80401:
October 4th - Top 10 Mine Operating Standards
October 5th - Top 10 Dragline Operating Standards October
8th - Top 10 Mine Operating Standards
October 9th - Top 10 Operating Standards
Contact Karen.Trott@gbimining.com
or go to http://www.gbimining.com/GBI-Training.html
for more details.
Tuesday, 28 August 2012
Best Practice Standards Series - Top 10 Dragline Operating Standards Feedback
On 28th August 2012 GBI conducted its Best Practice
Standards Series - Top 10 Dragline Operating Standards Course. We wanted to
share with you some of our feedback and the course rankings:
"Overall very useful and informative course. Covered
a broad range of topics well. Information was presented objectively with
supporting data and facts which was very valuable."
"Very good dragline course. Bucket and rigging
section was very involved obviously due to the large amount of knowledge GBI
has amassed in this area. Well presented and the info was delivered at the
right level for the target audience"
"Great workshop overall, very informative on a range
of levels."
"Being relatively new to Dragline operations and
management, this course has been really beneficial."
The course achieved an overall course ranking of 4.68 out
of 5. Where 1 is poor and 5 is excellent.
The Ranking for Content achieved was 4.42 out of 5.
The next Best Practice Standards Series are to be held on
the following dates at Colorado School of Mines, Golden, CO 80401:
October 4th - Top 10 Mine Operating Standards
October 5th - Top 10 Dragline Operating Standards
October 8th - Top 10 Mine Operating Standards
October 9th - Top 10 Operating Standards
October 5th - Top 10 Dragline Operating Standards
October 8th - Top 10 Mine Operating Standards
October 9th - Top 10 Operating Standards
Contact Karen.Trott@gbimining.com
or go to http://www.gbimining.com/GBI-Training.html for more details.
Monday, 16 July 2012
Truck and Loader Matching Part 5
This blog continues to
investigate the issue of why many trucks are being perfectly loaded in 2.5 or
3.5 passes. In this discussion I am looking at rope shovel capacity and
why we need so much steel to carry what is often a very poor payload.
How is it possible that best practice in
dipper performance provides a payload of 2.16 times capacity but the dominant
manufacturers provide dippers which only achieve around 1.70 times
capacity? This is more than 20% less payload for the same capacity and
around the same weight of steel. This rhetorical question actually has a
real answer. It is because the mines don’t care. So
long as it keeps going and is supported when it breaks then that is OK.
Many mines don’t even complain when the loader truck match is 2.5 or 3.5.
To someone who has worked in equipment productivity for over 20 years this is
really depressing.
Looking at some issues which
impact shovel payload. Firstly, dipper issues which the mine can have
some impact on. The tooth attack angle is really important. Payload
increases by around 0.5% per degree as the tooth attack angle is
increased. However, it is not possible to simply keep steepening the
tooth attack angle of the dipper due to the interaction between the heel and
the bank. Relative heel wear rises exponentially after about 65 degrees
tooth attack angle. By 70 degrees the heel wear is probably unacceptably
high. Many buckets are in the range 50-55o and are losing a
lot of payload.
The concept of Bail vs Bail-less is a function of where the hoist
connection is made to the dipper. The
connection of hoist ropes at the rear of the dipper increases payload.
Where the connection is 25% along the dipper the difference is -10% which is
significant.
The width : height : depth ratios
as well as teeth arrangements have an impact on payload but there is little
impact site people can have on these issues once you have the dipper so I won’t
expand on these issues here.
The other side of the payload
issue is operational issues. Many of these can be controlled by the
mine. What is being dug causes variation in average payload by up to 20%
in the same dipper. Herein lies a significant issue relating to truck/shovel
matches. It is possible that the same dipper, even on the same minesite,
can get differences in payload of 20% simply due to the spoil being dug. The key to higher
payload is the degree of fragmentation. The highest payloads are achieved
in spoil where there is a range of particle sizes; not all large and not all
small. The implication is that payload is significantly enhanced by good
blasting practices.
The power made available to the
operator has a major impact on payload. In harder digging, ie. blocky,
poorly shot, etc., increased power provides increased payload up to 120% of the
standard power level. In softer spoils the shovel dipper achieves higher
payloads at lower power levels. In summary, it is beneficial (in terms of
payload) to increase power to the maximum.
Bench height plays a major role
in determining payload. At any bench height greater than 30% of boom
point height a full payload can be achieved consistently. Similarly, the
distance from the face has a major impact on payload. The variation from
cycle to cycle is quite large but a consistent trend is seen for each digging
position. The first few digs have the loading unit very close to the
face. During these cycles the payloads are reduced possibly due to the
inefficient application of power to the trajectory of the dipper / bucket.
The payload increases as the face “moves” away from the shovel. Once the
dipper starts having trouble reaching the face the payload reduces quite
quickly. The decision about when to move the loader is not an easy
one to get right. Generally the operator will decide to move the loader
when they encounter difficulty in loading the truck in the designated number of
cycles. To optimise the productivity a range of factors need to be
considered, including, payload, fill time, another truck waiting, what the face
is like. As a general observation, if the loader is under-trucked, it
would appear prudent to move the loading unit frequently. If the shovel
is over-trucked it becomes a multi-dimensional equation as to when the most
efficient time to move is.
It became evident from a very
early stage in the work on shovels that on some loading equipment the
efficiency of the bucket / dipper was severely compromised by large voids
inside the dipper / bucket (Figure 1). These voids ranged from 5% inside
a backhoe bucket up to 25% inside rope shovel buckets. The impact of
these voids is included in the previously described impacts on payload.
Finally I would direct your
attention to Figure 2. This shows the variation in dipper payload for
P&H and Cat (previously Bucyrus), (both unidentified) and VR Mining
Dippers. I have spent my career helping mines be more productive and the
VR Mining dipper is the most efficient dipper design I am aware of. I am
aware there are maintenance, support and financial issues to purchasing a
dipper but speak to dipper manufacturers, not just the OEM, the next time you
want a dipper.
Just so you know: I worked for
VR Mining in 1997 and 1998; before they designed this dipper. GBI has had
a number of small consulting jobs from VR Mining over the last 10 years.
I had no input into the VR design. Neither I nor GBI receive anything
from anyone for the comments made here. They are simply my honest opinion
– the VR dipper is the best and the mines are costing themselves a bundle by
not looking at it. Even if the mines used this fact to put pressure on
P&H and Caterpillar to do better, the industry would benefit.
Wednesday, 11 July 2012
Truck and Loader Matching Part 4
Over the last few weeks I have
systematically pulled apart the issue of nominal truck capacities to
demonstrate why big mining trucks achieve 5-15% below what the manufacturer
says they should get on average. I don’t believe this is an issue that
too many truck manufacturers’ want to address and the cynical side of me
suggests that this article won’t help. Maybe a single voice in the
wilderness can gain support to force change.
My focus is on mines moving
more for less and apart from the engineering design work to increase the
capacity of trucks from the 150 tonne maximum size 25 years ago to the 360
tonne maximum size now I don’t think that the truck suppliers have helped the
“move more for less” equation too much. Even the notion of bigger trucks
being a great innovation and assistance in efficiency enhancement is
questionable. I will repeat something from a previous blog. On the
whole bigger trucks are less efficient than smaller trucks. They carry
less payload (as a percentage of nominal capacity) and work less hours.
However, this is not a consistent picture between OEM’s. In terms of
nominal capacity the 360 ton trucks are 50% bigger than a 240 ton truck.
however, in terms of actual annual capacity, average 360 ton trucks move just
20% more than 240 ton trucks. I am not pointing the finger at one
supplier.
Figure 1 shows the 2010 median
performance for each major mining truck make and model. Some of the older
and newer models are not included due to lack of data. Mining truck
performance is presented in this analysis as annual tonnes (normalised for full
year operation) * km travelled per tonne of nominal tray carrying capacity.
Trucks with different
designations (usually A, B, etc used by Cat and Liebherr) have not been
separated in this analysis. The capacities for these “sub-models” are
generally similar as is the output. It is important to note that
this plot does not attempt to say whether the make and model results actually
reflect better trucks or the operating characteristics of the sites at which
they are used. The trends with increasing size of mining trucks are
mixed. The Liebherr trucks become more efficient with increasing size
while the Cat trucks become less efficient with increasing size. The
Hitachi, Komatsu and Terex trucks achieve peak efficiency with the 240 ton (218
metric tonne) capacity size EH4500, 830E and 4400 respectively. The
larger capacity trucks are not as efficient with these OEM’s. Of the
larger trucks the Liebherr T282 is the highest performer with Terex and Komatsu
both achieving 20% less annual tkm/t and Cat 23% less annual tkm/t. It is
not without precedent for larger equipment to have lower unit production (ie.
draglines) however, the exceptional performance of the Liebherr T282 range
demonstrates that this is not a necessary outcome. Another clear finding
from this plot is that the performance of the smaller Cat trucks (777 and 785)
was, and continues to be, relatively high. They however, are not suitable
for loading with the larger loaders.
This industry has lived in a
world where bigger is better. But frequently when bigger equipment is
released it just doesn’t perform well. Those of us who remember the
release of 240 ton trucks would remember that they had real problems. It
seems too easy for a poorly performing mine to just get bigger equipment and
that is what they tend to do. They waste more millions of dollars when
the improvements they need are available by just operating more efficiently and
would actually cost very little.
To demonstrate this point I
will set up a scenario of a PC8000 hydraulic shovel loading Cat793
trucks. These have not been chosen for any particular reason except it
should be a comfortable three pass match. The average PC8000 loader will
require 7.5 average Cat 793 trucks. Four crews plus spares plus trainees
(you should always have a pool of people training) probably means around 40
truck drivers. If a mine then goes and purchases Cat797 trucks the
typical method of determining number of trucks is to simply work out the
proportional capacity. New trucks = old trucks * 793 capacity / 797
capacity. Using this formula five new Cat797 trucks would be purchased
with the expectation that around 13 people would be saved along with reduced
running and maintenance costs. Unfortunately, this scenario is
fictitious. In the real world the PC8000 on average needs 5.8 * 797
trucks and only saves 9 people. Bigger trucks cost more to buy and more
to run, so how far ahead are you?
OK so returning to the real
point of this column; technology is progressing fast. We now know that
trucks are not carrying the nominal payloads. This has not gone unnoticed
by companies which make their way in the world by making equipment work
better. For the OEM the real money seems to be in the chassis and
tyres. Improvements in payload are coming from specialist tray
suppliers. Truck trays are no different to most other mining
equipment. What the equipment carries is made up of steel and payload and
the aim is to maximise the payload and minimise the steel while achieving
acceptable life. In the past with trucks this was a nothing equation
because OEM’s told the mine what payload the truck would carry. We now
know this was almost always wrong. Truck trays seem to be following where
the industry has been with draglines. Now Bucyrus and P&H build
draglines and shovels but CQMS currently build the most efficient dragline
buckets while VR Mining have the most efficient shovel dippers. In trucks
you have specialised truck tray manufacturers like DT HiLoad, Duratray, Esco,
Philippi-Hagenbach, Westech, etc. who seem to get it; the chassis is built to
carry a certain load and if you can reduce tonnes of steel and increase tonnes
of payload then the mine must be ahead.
It is my proposal that we must
here and now dispose of SAE Standard J-1363 for calculating truck capacity the
same way suppliers have disposed of the CIMA formula for dragline bucket
capacity. We must also stop rating trucks based on a nominal
payload. We should establish a rated capacity for the truck trays which
is struck capacity (contained capacity with no heaping according to computer
models) multiplied by a factor. With dragline buckets the factor is 0.9
which I have always disagreed with but everyone knows it and accepts it.
I believe the rated capacity of a truck tray should be equal to the struck
capacity, (factor = 1). In the same way that we have a Bucket Efficiency
Ratio for draglines and a Dipper Efficiency Ratio for shovels, which is payload
/ rated capacity, we need a Tray Efficiency Ratio (payload / rated capacity)
for trucks - TER. There is also a steel weight ratio (Tray Unit Weight
(TUW)), which is the weight of the tray divided by the rated capacity. The
formula for the optimum truck tray rated capacity is then;
OTC
= GVM – Chassis Wt
TER + TUW
Only then can we get the best
tray design with the right capacity to meet the gross vehicle mass. At
least then we will be covering Step 1 in the optimisation process; mines will
be selecting the right piece of gear.
Tuesday, 15 May 2012
Truck and Loader Matching Part 2
I have seen many examples of
trucks being loaded perfectly in two and a half or three and a half
passes. As I said in the last blog, for many mines the issue of matching
truck capacity to loader capacity is problematic and more often than not
results in a majority of trucks being under-loaded. As trucks and loading
units increase in size the number of passes required to fill the truck is
decreasing and the difficulty in attaining the match is becoming more
difficult.
Mines generally use one of five
methods for selecting equipment size/capacity.
1. Allow the supplier to decide. Suppliers love this
because they can sell the mine the same as someone else has received which cuts
down their costs significantly. However, if the mine abrogates their
responsibility to run their mine they get what they deserve. Remember back
last year when I discussed the 62.7 CuM rope shovel. The calculation had
fill factors and all sorts of multipliers to arrive at the correct
answer. However, you don’t need to be as cynical as me to be struck by
the fact that it was exactly the same dipper being used on exactly the same
make and model shovel at a mine about 150km away. Were they digging the
same spoil? No. Were they using the same bench heights? No. Surely
they were at least loading the same trucks? No. A completely different
operation and yet (quite by chance?) the supplier came up with the same dipper
as being the right size. Mining with a computer is really easy but it rarely
provides the answer which will help the mine optimise what they are
doing. Understand this – if you allow the supplier to specify the size of
the equipment you will get the capacity which is best for their profit, not
yours. It saves them much design, engineering and fabrication cost if a
supplier can simply sell you the same capacity that someone else has.
A
quick example from the coal mines on suppliers providing the same product when
something different was needed. A mine ordered a dragline bucket from the
dominant supplier. In this case the supplier has about 75% market share
and the mine was justified in choosing them. After doing some computer
mining the bucket supplier arrived at 57 CuM capacity. Once it went to
work the mine was very unhappy with its performance as the average payload was
about eight tonnes below what they previously achieved and the operators were
complaining about it not digging. We were called in to investigate.
We found the geometry of the bucket was not matched to the geometry of the pit
being dug. I found the exact same bucket had been built for another mine
about 9 months earlier and they were very happy with it. This operation
had an average pit depth of 50 metres and the design matched perfectly.
The second 57 CuM bucket was exactly the same as the first but the
digging depth rarely exceeded 20 metres. End result – the mine lost substantial
production and potential profitability. Anyway, back to the other methods
of selecting equipment capacity.
2. Guess. There are a number of
forms which this takes. Most people in the selection process will create
the “truck-loader” matching spreadsheet but will make a number of guesses about
key factors on density, fill factors, etc. Often this process is aimed at
justifying a particular capacity to management.
3. Existing Data. This is an extension on
guessing. Data is collected on existing performance and this is
extrapolated to new equipment. This is certainly a quantum leap up from
options 1 and 2 but can fall down when data is sketchy or non-existent or when
different equipment is ordered.
4. Computer modelling. This is an extension on point
1. Some suppliers have flow models for simulating material flow into
their equipment but while being good for research and development, they are of
minimal value for commercial decision-making. This is due to the models
not being far enough advanced to simulate specific spoil (as opposed to generic
spoils). Now I might get howls of opposition from highly intelligent
researchers but I have never seen one good enough for commercial
decision-making.
5. Physical Modelling. In 1977, D.J. Schuring,
released “Scale Models in Engineering: Fundamentals and Applications”, Pergamon
Press, New York, N. Y. In this book, he devoted a section to earthmoving
in general, (eg. Bulldozers, excavators, etc), in which he confirmed the
accuracy of physical modelling in earthmoving applications. Scale models
have been used successfully on dragline buckets and rigging since 1985.
Similar techniques have been applied to rope shovels since 2000, truck bodies
since 2002 and excavators since 2005. Schuring (1977) found that the key
to accurate results from scale models in earthmoving was that the behaviour of
the spoil was accurately simulated.
In my next blog I will carry
this discussion on and look at the flawed standard being used to determine
truck nominal capacity.
Graham Lumley
BE(Min)Hons, MBA, DBA, FAUSIMM(CP), MMICA, MAICD, RPEQ
Wednesday, 28 March 2012
Mining and complexity – paradigm, paradox or parody?
I introduced the issue of
complexity in my last blog and stated that there is little evidence in open cut
equipment production data that “complexity” plays any role in decreasing
equipment productivity over time. This is a controversial view in the
mining industry, particularly the large mining companies where increasing
complexity has been used as an excuse for falling equipment productivity rates
for some years now.
I stated in my last blog;
It is my theory that the corporatisation
of the mine site is to blame for the reduction in availability and consequent
productivity. It is the focus on process and not the result.
Managers are often judged on how they do their job, not the end result, and a
declining result can be hidden behind exceptional processes. Part of that
change is an increasing focus on safety but not the majority of it.
Because most managers have little real natural management expertise they
embrace the processes which are encouraged by corporatisation. Six Sigma
or Lean are great because they provide the manager with a focus on
process. You can actually point to what you have done.
Unfortunately the performance metric is wrong.
I believe that the silent
majority support this view but many just have to fit within the confines of the
company that employs them. I received the following from someone running
a mine this week after they read my last blog (that makes two of us who read
it).
You are so right about people
getting hung up about the process of a process and the process of process
improvement rather than the bottom line impact of the outcome it produces
You can extend this further by
explicitly focussing on added value as the principle and proper measure of
improvement. eg "For any given operational outcome, a process
'improvement' that does not measurably generate positive added value or improve
safety without negative impact on the firm's overall value is no improvement at
all." No matter how exceptional it might be.
This industry needs to take
more notice of Prof Michael Porter - the father of the value chain concept. He
had it spot on. If it doesn't add measurable value, prune it.
However, remember not all value is financial - reputation, employee wellbeing,
and other "soft" forms of value also matter to different degrees in
different companies.
Six Sigma and Lean do not cover
the value chain concept well I reckon, and their experts too frequently have no
wider business management training to know any better.
A few other personal
operational observations for you;
- Pits do get more complex
sometimes but usually just deeper and/or less "rich". Any
complexity is mostly human induced.
- You are right about
availability being a function of age. BUT its more complicated and its
only true beyond a certain age. There is a trade-off between depreciation
of new equipment with age and repair with age on 2 axes vs availability
with age on the third. If you map profit (or net value added) against
these axes you will find here is a reasonable sweet spot for average fleet
age where profit is maximised - and it’s not at any of the extremes.
Operational rosters (eg 4 days a week, 24*7 etc) change the sweet spot
quite a bit.
- I've never seen any specific
mining industry research on this and there are a lot of misconceptions out
there.
- Availability is an issue but
not the only one. Cost saving pressures, lack of professional knowledge,
managerial ignorance and inappropriate performance metrics are an even
bigger part of it. Maybe some would argue this is the actual
"complexity" causing most of the problems, eg...
- Payload and digging cycle time
(esp truck shovel) are affected (often severely) by poor pit design
(relative to deposit and equipment), poor road placement, poor matching of
blast performance, poor dump design, but also limited communication
between the engineers and mining supervisors - the latter usually make the
shift to shift decisions with no knowledge or understanding of the
former's work (= poor decisions frequently).
I will repeat my last paragraph from the last column. Commodity prices (maybe with the exception of gold) are going to decline. You won’t be able to keep making money without focusing on the real reason you are in business. You need more of your commodity going out the gate at a lower cost, not a new business improvement process every week or month.
Graham Lumley
BE(Min)Hons, MBA, DBA, FAUSIMM(CP), MMICA, MAICD, RPEQ
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Tuesday, 20 March 2012
Complexity and Productivity
If you were to ask a mining
executive why their mines’ equipment performance has reduced over time, apart
from spluttered expressions of disbelief from some you would certainly get the
issue of mining complexity fairly high in the excuses. This is because
site people use this excuse almost universally when asked why their performance
has reduced. It seems logical that mines dig the easiest / most
profitable areas first and conditions do generally become more difficult over
time.
When executive management
starts holding site people accountable for the equipment performance it is
interesting to see what happens. It usually goes something like this;
- Dry up the source of the bad
news – ie. stop benchmarking. “We know we are 40% below best
practice so why keep telling Executive Management”.
- Advise management that reducing
performance is a function of complexity of the mine. “We know it is
getting worse and we know it must be the increasingly complex mine we are
running.”
- Create a picture of how
complexity reduces digging hours or increases cycle times, etc.
However, should equipment
achieve less output as the mine becomes more complex? This really is a
perfect example of not letting the truth get in the way of a good story.
We have looked at this issue from multiple angles and we can’t find any
evidence to support this notion that complexity reduces the performance of a
particular piece of equipment. Even for trucks if you use an appropriate
measure of truck performance there is no consistent reduction in performance.
Of course as a mine gets deeper and more complex, more equipment may be
needed. This is a completely different issue.
So let’s look at the
truth.
The absolute key to the
performance of any piece of equipment is payload. I can’t find any logical
explanation as to why complexity should consistently impact payload. The
only possible impact could be in bench heights and/or pit layout.
However, if superintendents and engineers do their job there is rarely a reason
not to set the pit up to ensure optimised payload. The differences in
payload (eg. The difference between dragline best practice and average is 17%
and other equipment is similar) are inevitably caused by other factors.
The most common and most distressing is mines telling operators not to fill up
the bucket or truck body and kicking the operator when they do!!! For
heaven’s sake the operator’s job is to fill up the bucket and he/she should be
encouraged to do this to the best of their ability every time. If it is
overloaded then don’t blame the operator; this is a management failure.
OK so it can’t be
payload. Is digging time related to complexity? The key area that
gets blamed is operational delays and most specifically waiting on equipment or
blast. We have tracked operational delays and we know that when
productivity drops, about 40% of the drop can be linked to operational delays
but only about 6% is linked to waiting on something. So really it has
little to do with waiting on equipment or blast. Yes there is a relationship
between complexity and operational delays but the major loss in productivity is
found elsewhere.
Often the major contributor to
a loss in productivity over time is availability. What happens is that
there are two key relationships. Complexity increases with time and
availability tends to reduce with time. The truth is the two
relationships are only linked in a very minor way. So is it equipment
getting older and harder to keep going? Maybe, but old equipment does get
replaced and the trend does continue.
It is my theory that the
corporatisation of the mine site is to blame for the increase in operating
delays; the reduction in availability; and consequent reduction in
productivity. It is the focus on process and not the result which is
primarily to blame. Managers are often judged on how they do their job,
not the end result, and a declining result can be hidden behind exceptional
processes. Because most managers have little real management expertise
they embrace the processes which are encouraged by corporatisation. Six
Sigma or Lean are great because they provide the manager with a focus on
process.
A bit of a wake-up call
here. Commodity prices (maybe with the exception of silver and gold) are
going to decline. You won’t be able to keep making money without focusing
on the real reason you are in business. You need more of your commodity
going out the gate at a lower cost, not a new business improvement process
every week or month.
Graham Lumley
BE(Min)Hons, MBA, DBA, FAUSIMM(CP), MMICA, MAICD, RPEQ
Sunday, 5 February 2012
White Paper - Trends in Performance of Open Cut Mining Equipment
GBI is excited to announce the release of Graham Lumley's White paper on Performance Trends of Open Cut Mining Equipment.
Using our extensive (and rapidly expanding database), Graham has been able to glean some interesting and sometimes disturbing trends across the various makes and models of machines in the open cut mining space.
Take a look at the White paper here.
If you would like to discuss the findings of this white paper in further detail with Graham or perhaps understand how you can use the information held by GBI to further your productivity improvement please contact us at GBI (gbi@gbimining.com) or Graham directly (graham.lumley@gbimining.com).
Using our extensive (and rapidly expanding database), Graham has been able to glean some interesting and sometimes disturbing trends across the various makes and models of machines in the open cut mining space.
Take a look at the White paper here.
If you would like to discuss the findings of this white paper in further detail with Graham or perhaps understand how you can use the information held by GBI to further your productivity improvement please contact us at GBI (gbi@gbimining.com) or Graham directly (graham.lumley@gbimining.com).
Thursday, 2 February 2012
Productivity and Mine Planning - Part 3
Mining companies don’t have the
equivalent of the magic pudding (with apologies to Norman Lindsay for the
analogy). They have limited resources with which to create a return for
their shareholders and as they are mined they deplete. For all mining
companies there is continual pressure to turn what is in the ground into a
financial return. This is one side of the issue which sees productivity
rates and costs used in mine plans almost always optimistic. I suspect
the old saying, “Don’t let the truth get in the way of a good mine”, or
something like that, is pretty apt. The other side of this problem is
that despite what most mine planners (consultant or company) say they don’t
have enough data to provide (statistically) credible inputs. The
decision-making process by executive management and many Boards of Directors is
at best doubtful, usually flawed, and in some cases, just downright dishonest.
This week I will use an example
of a job we did for a mine planning consultant as a demonstration of how the
mine plan goes seriously pear shaped. I should emphasise that in this case the
consultant is using real inputs; they do understand the issues; and will be
using the information correctly. Shame they are in the minority!!!
The request was for benchmark
information for an RH 340 hydraulic excavator with 34 CuM bucket
capacity. The first point to note is that in the particular application
being looked at, the worldwide, average annual output for these machines was
12.6 million tonnes while best practice (average of the top 10%) was 23.1
mt. Just a small difference there. Can you believe a best practice
RH340 moves twice as much as the average? The natural tendency for the
mine is to think, “of course we are good” and for the consultant to want to
provide the best outcome. More often than not a rate somewhere in the
vicinity of, or above 75th percentile is used. However, you have to be
realistic. Only one in four mines using the RH340 will achieve 23 mt or
higher and maybe you are one of the 3 out of 4 who won’t. If you have
always had average performance then why would it suddenly improve?
The second issue is why do some
people believe that a piece of equipment will move well over best
practice? This example provides the perfect demonstration. The
request from the mine planning consultant was for a benchmark of availability,
utilisation and dig rate. That is, they wanted 25th percentile, median,
75th percentile and best practice of these three KPI’s. The availability,
utilisation and dig rate combine to produce the annual output. The
problem is that there is no mine in the world using this loader where they
achieve best practice availability, best practice utilisation and best practice
dig rate. In fact if you take best practice for these three KPI’s the
output is in excess of 27 mt compared with the actual best practice output of
23 mt.
A number of human factors are
at play here. Firstly, different companies have different definitions of
the KPI’s. Availability for one company is not availability for another
company. So for mine X to say they achieve 90% availability and that
makes them good is wrong. Worse still is the executive who just simply
applies numbers without understanding what they mean or what is included in
them. Secondly, people use results achieved for short time frames and
apply them to longer timeframes. Availability or utilisation achieved
over one to three good months normally bears no semblance to what is achieved
over 12 months. A third problem is people extrapolate rates in a straight
line up from smaller equipment and this is often not correct. There are a
range of factors at play as sizes get bigger. For example, a best
practice 218 tonne truck will carry 208 tonnes (95.4%) while a 327 tonne truck
will carry 301 tonnes on average (92.0%). Another example is
draglines. An M8050 with 50 CuM bucket will carry 107.5 tonnes of payload
(2.15 t/CuM) on average and an M8750 with 100 CuM bucket will carry 200 tonnes
at best (2.00 t/CuM). Add to this the fact that bigger equipment operates
for less hours and you will understand why you can’t just extrapolate up.
A fourth mistake which people make is to apply results from one manufacturer
and say that the same equipment from another manufacturer will be the
same. It isn’t. As an example the difference in actual annual
output between different manufacturers’ hydraulic excavators in 2010 with 30-34
CuM buckets was up to 84%. (Oh by the way, which one did you buy?)
At the end of the day we are
interested in what the equipment will move in a defined time. The defined
time will depend on the level of accuracy required of the plan. If it is
a really short term plan (next shift or day) we might use the dig rate, (what
is moved per operating hour). As the time frame goes up more and more operational
factors come into play.
I have a real issue with what
some mine planners (company and consultants) are doing. They don’t have
sufficient data nor knowledge about performance but tell you they do. I
simply ask that if they have the information then why are mine plans
continually wrong?
OK, some companies don’t want
the truth but some do. The "mine development industry" will
continue to get away with producing poor plans until we as an industry
plus shareholders and stock exchanges hold them accountable; now, 3 years, 5
years, etc into the future.
Graham Lumley
BE(Min)Hons, MBA, DBA, FAUSIMM(CP), MMICA, MAICD, RPEQ
Sunday, 13 November 2011
When to spend on innovation
I have
introduced a number of broad-based productivity issues over the last few
blogs. We will get on to some more specific issues but in this piece I
want to introduce another broad issue. What is the best time to invest in
productivity enhancement?
The two key
areas to productivity enhancement are during the R&D / equipment selection
phase and during the post-commissioning phase. That is, get the right
equipment and optimise its use.
To understand
the interaction between mining and knowledge I will return to the presentation
by Jari Kuusisto presented to the Smart Innovation Festival in Brisbane in May
2008. Kuusisto presented the curve of ROR vs Product Life Cycle. I
have added the risk and cost benefit to this to provide the following plot.
The product
life cycle can be described from the mine or the supplier’s perspective.
In the plot here it is viewed from the mine’s perspective. The mine
follows a process of Correct Selection – Order placement – Commissioning –
Equipment Enhancement.
The rate of
return on money invested is highest during the development / selection stage of
the product and during the after-sales service / equipment enhancement
phase. However, the risk on the investment is highest early in the
process and reduces further after the product has been delivered.
When these two plots are combined it can be easily seen that the cost-benefit
(return / risk) is moderate at the start of the process (during R&D /
selection) and highest after delivery/commissioning (during the process of
“asset optimisation” or “capacity utilisation”). It is no coincidence
that the application of knowledge is needed most during these two
sections. It can therefore be deduced that the input of knowledge is
related to cost benefit. It is also interesting to note that the highest
cost benefit occurs when the knowledge is applied in the after-delivery phase
of equipment optimisation which is largely process related.
If one looks
at this from the perspective of a supplier the product life cycle
becomes: R&D, Collect Orders – Commissioning – After Sales Service.
Interestingly, the plot follows exactly the same form. For the equipment
supplier their greatest return comes in after-sales service. This is a
really interesting observation because during the boom I had an almost
impossible job getting suppliers to listen to anything to do with knowledge and
after-sales support. Suppliers apparently were able to sell all their
equipment and the concept of using after-sales service and knowledge as a means
of helping mines use their equipment better and as a point of strategic
advantage wasn’t considered. This has clearly changed. I have had a
number of companies approach us about using the data and knowledge as a key
element in their marketing strategy. During the boom nobody seemed to
care that there was one brand of truck which was 84% more efficient than the
worst. Funny isn’t it? During the boom if it had wheels and carried
dirt it was good enough. Now a lot of mining people don’t seem to want to
take the risk that they will buy the worst truck and some suppliers seem
motivated to use data to help them be as good as their equipment allows them to
be on the mine sites.
It seems
prudent for suppliers to understand the words of S. Downton on
ecustomerworld.com,
Delivering high levels of
customer satisfaction through a well-managed service operation can increase loyalty,
and thereby sales, by as much as 8 times - greatly enhancing the value of the
business. Successful manufactures increasingly focus on their customers' total
lifecycle by investing in their service management business to maximise the
value captured throughout the product lifecycle. This means that the product
sale is only a small part of the overall value during the complete product
lifecycle and is only the start of the customer relationship.
Support for
my belief that the world of suppliers has changed came late last year when we
found a bucket manual which I had written for a mine to optimise the
performance of the bucket they had just purchased, had been blatantly
plagiarised by the OEM and presented to other mines purchasing their product
under their name and logo. This supplier has seen the value of knowledge
(particularly linking the knowledge to the company) and has seen it as
providing strategic advantage for them.
Graham Lumley
BE(Min)Hons, MBA, DBA, FAUSIMM(CP), MMICA, MAICD, RPEQ
Monday, 7 November 2011
Knowledge Intensive Mining
I have addressed the issues in the previous couple of blogs about the
poor use of knowledge and value adding through innovation by the Australian
mining industry. I have been quite negative about how the Australian
mining industry is performing in this essential area. So rather than
always be negative, the aim of this discourse is to describe a process and a
culture which will form the foundation of improved performance through
knowledge-intensive mining.
With some hesitation I return to University and 1st Year
Chemistry. We consider a reaction with a desired result. The
chemical reaction requires reactants and a catalyst. To achieve the
desired reaction (adding value through innovation) we need the correct
reactants (processes) and catalyst (culture)
If you knew that there was an M8050 dragline that achieved 21 MBCM
annually (17% higher than the next best), would you want to know how? If you
knew there was an EX5500 excavator which achieved 12% higher than the next
best, would you want to know how? Most people do and this type of broad
information is the foundation of knowledge-intensive mining (but it doesn’t
stop at the broad-based information). The following definition is
proposed for Knowledge-Intensive Mining:
Knowledge-intensive
mining is the acquisition (from internal or external sources); absorption
(through active understanding) and application (via systemic processes or
one-off projects) of knowledge which improves the mining process.
The steps to gaining the tangible improvements, whether they be due to a
change in the machine or mining process, must be preceded by a number of steps
of gaining the intangible knowledge. Each individual needs to be accountable
for their own attitudes and actions, regardless of their position. Not everyone
keeps detailed records of everything he/she does, recognise some form of
sub-optimal result, does something different, etc. What is needed is
people doing business improvement on a “micro scale”. What that means is
when a person sees something happening which is sub-optimal they immediately do
something to change it. For an operator an example might be a half full
bucket or poor positioning on a block. Improving this doesn’t take a BI
program but if you look at it, a very similar (undocumented) quality / six
sigma / lean process is taking place. To achieve these gains you don’t
need a BI program, you need a focussed and motivated workforce / team. To
get this you need the processes and the culture. Each person up the
management line, Operator, Foreman, Supt, Manager, General Manager, etc. needs
to take this micro approach to business improvement and it appears clear that
many are not. All too often the upper level manager is too concerned with
“ticking the boxes” and / or not making a mistake to worry about really using
knowledge to achieve innovation. After all, their performance is normally
judged on how many mistakes they have made, not how innovatively they have
acted.
Whether work is in coal mining, hard rock mining, infrastructure,
environment, or wherever, the messages are the same: Firstly, the idea
that only tangible things add value must be changed. We must value
knowledge. We must actively acquire knowledge, absorb it and apply it to
add value through modifying processes. Remember, processes are the
innovation reactants. They are the aspects which combine to produce
productivity.
Changes to them are sometimes hard to grasp or understand but they are
none-the-less the fabric of performance. Secondly, culture is
the innovation catalyst. Not change for the sake of change but rather
change which is targeted at the bottom line.
So what do we do about culture? This is the more difficult question at
all levels of the mine but if we look at management there are two key issues to
do with culture. Firstly, the attitude of rewarding people who don’t
“stuff up” must be changed. If you aren’t allowed to be wrong then your
employer won’t ever achieve anything. Companies must reward people who
are prepared to take measured risks even if those risks fail.
Anecdotally, it is smaller companies which encourage innovation but they don’t
always respond well to failure so their support of innovation is not always
useful. If you are rewarded for not “stuffing up” or if you work for a
company which describes itself as a “fast follower” then find another company
which encourages innovation. Secondly, you must believe you have a right
to be wrong. If you as an individual aren’t prepared to be wrong then you
won’t ever achieve anything. Unfortunately our education system, which I
admire greatly (I am married to a teacher who I met in a small town in the
middle of nowhere), encourages people to be right. There is little
encouragement to be innovative and get it wrong.
It is these attitudes (or lack of them) which is strangling the
advancement of the Australian mining industry.
Graham Lumley
BE(Min)Hons, MBA, DBA, FAUSIMM(CP), MMICA, MAICD, RPEQ
Tuesday, 1 November 2011
Sunday, 30 October 2011
From knowledge to innovation
In my previous blog I discussed the creation of knowledge and adding
value through change (innovativeness). The big step forward which is needed for
the mining industry is a better understanding of the link between knowledge and
innovation. The innovation process has four characteristics.
1. Being
part of the global world. Knowledge is everywhere and there is good
work being done around the globe. For example, Europe is not renowned for
mining knowledge (although maybe Russia and several of the former Russian
States may be exceptions). Many of the European countries fall in the top
quartile for innovativeness and as such frequently have developments of
interest here in Australia. In addition to a number of large equipment
companies from Germany which are doing some good work, there are real
technology advancements coming out of Europe. The Vienna Test System
which comes from Austria has tremendous application in the Australian mines for
operator selection; significant electrical advancements are being made in
Germany and tested on draglines in Estonia; etc, etc. Mines should be
grasping knowledge and/or developments from anywhere they might come. As
a primary consideration they should be benchmarking wherever possible.
2. Innovative
individuals and communities. The mining industry needs innovative
people. I have mentioned it before but the perfect example is the
Australian Coal Association Research Program which distributes over $10M
annually of the industry’s money for coal mine research. This program
draws some of the smartest and most innovative thinkers into the coal industry
research and development arena. To ACARP’s credit, they do get the whole
concept of knowledge development and the link to innovation and have a clear
focus on adding value. AMIRA also plays a vital role for the broader
mining industry. Mines need to build an innovation culture where change
is not done for the sake of change but rather to add value.
3. Systemic
Nature. Being innovative is not something which can be turned on and
off. It is the culture; the way the people think and act. Some
people believe it is difficult being innovative within a large mining
company. This is because they are thinking on too large a scale.
Too often we think that multi-million dollar projects such as Universal Dig and
Dump, equipment automation, etc. are required to be innovative. However,
knowledge intensive mining and being innovative can be done on a
micro-scale. Each person can take responsibility for themselves and can
follow the path of acquiring, absorbing and applying. On a micro-scale
the operator who, having difficulty loading one bucket ends up with half a
load, actively changes their digging for the next cycle and the one after that
has applied knowledge. As a summary, each individual being innovative relies on
how they are acquiring, absorbing and applying the knowledge which is
available.
4. Customer
and user-centric. This is what I call “bottom line” service.
From the provider’s perspective, knowledge and service provision must be
focused on what the user / mine needs. All too often the mining industry
funds work by research groups and consultants, which focuses on the process and
how smart the process and people are. For knowledge to be valuable and to
facilitate the innovation process it must be value-based, ie. it must provide
bottom-line / profitability improvements for the mines. The key to this
is the person pulling the levers or turning the steering wheel. This
person has the ultimate control over what output is achieved. Therefore
the mine must engage the operator / driver in the optimisation process.
In the European Innovation Survey, Australia fell in the third
quartile. We are below average in innovativeness, and by industry
standards the mining industry is very conservative. In fact, I could name
quite easily those mines in Australia which I consider to be genuinely
innovative. The reasons for this are quite clear and I will address them
in my next blog.
Graham Lumley
BE(Min)Hons, MBA, DBA, FAUSIMM(CP), MMICA, MAICD, RPEQ
Labels:
data,
dragline,
GBI,
mining,
mining equipment,
productivity
Monday, 24 October 2011
Improving Equipment Performance – Knowledge & Innovation
The two steps
in business improvement for any process, including equipment performance, are
to gain knowledge (about gaps in performance) and to do something with the
knowledge (innovation).
There are a
number of generators of knowledge.
- R&D which needs policy to support R&D and money to do the R&D. The money attracts smart people to do the R&D. A really good example of this has been the ACARP program in the Australian coal industry. $10M+ of funding is available per year and some of the smartest researchers have been attracted to this money.
- Experience from time on the piece of equipment. The knowledge is gained from the interactions between the people and their environment.
- Training which is defined in terms of the content and the delivery / instruction generates knowledge for the trainee.
- Information, which is generated from data, becomes knowledge when it is meaningful to the recipient.
Experience
happens, data is collected and benchmarks done, training is provided and
research is done by various organisations, however the transition to knowledge
is not always done well. Many have said, "If you don’t measure it you
can’t improve it", but it is more than this. If you don’t actively
acquire it, absorb it and apply it, you can’t improve it. Internal
knowledge resides in the people and the captured data. External sources
may include trainers, researchers, consultants, market intelligence, etc.
The effective
generation and use of knowledge is being stifled at the majority of Australian
mines. Good management doesn’t just put red lines through a whole heap of
budget items. Good management is about cost optimisation in the short,
medium and long term; not necessarily short-term cost minimisation. Cost
optimisation always allows a budget cost (usually relatively small) to become
smarter and practice real continuous improvement. If an organisation
wants to stay operating during the difficult times ahead they really need to
spend some money to save more.
The expansion
of knowledge and the use of knowledge has attracted the attention of many key
mine people, however, the further one looks up through the corporate ranks the
less appreciation for the value of knowledge is apparent. Many people in
decision-making positions, struggle with grasping something which is not
tangible.
Most
Australian mines fail to take the steps to innovation. Getting a
benchmark or a consultant’s report or a mine plan demonstrates that the manager
is doing something. But really, if something practical isn’t done with
it, all he/she has done is waste the company’s money in an attempt to make
themselves look good and tick their career boxes. Without taking the step
to innovation / change, nothing of value is achieved for the mine. A
culture has developed whereby not taking risks is rewarded. "If you want
to get ahead don’t stuff up". Add to this the personal issues many
Australians have to being wrong and you can see why innovation is so difficult
for some mines.
The easiest
way to use knowledge and to add value is through using data to evaluate and
understand what is currently happening and to change based on the knowledge of
what others around the world are doing. It is not about the creation of a
simple one-page report from the monitor because chances are that it has been
written by an IT person with limited knowledge of what is meaningful. It
is about the active creation of meaningful reports and a program of helping the
recipients understand and plan to be better.
Labels:
data,
dragline,
GBI,
mining,
mining equipment,
productivity
Monday, 17 October 2011
Gaining Competitive advantage from Data
In this
discussion I intend to discuss how the vast amounts of data which are generated
on mining equipment can be turned into productivity, profitability and
ultimately competitive advantage. This is what I call “bottom line”
services.
There is a wealth of valuable mining data being produced around the world every day, however, mines are failing to benefit from it as they don’t have the ability to capture and meaningfully apply it. Through poor management of available data and the loss of personnel, the continuity of information acquired and knowledge applied to run mines efficiently is being broken. If not remedied, this will prove very costly in the long term.
Data by itself is just a mass of numbers - it needs to be analysed and assessed to extract value. However, mines must be wary of subjective analysis which is done for the benefit of another party rather than the mine itself. All too often the mining industry funds work by research groups and consultants which focuses on the process and how smart the process and people are. For knowledge to be valuable and to facilitate the innovation process it must be value-based, ie. it must provide bottom-line / profitability improvements for the mines. The key to this is the person pulling the levers or turning the steering wheel. This person has the ultimate control over what output is achieved. Therefore the mine must engage the operator / driver in the optimisation process. To do this they must have an intimate understanding of the information being provided through reporting of performance
A key part of this program was delving into the masses of data to provide specific and targeted reports to a range of people across the site. Remember the word “meaningful”. This is the key to operators and drivers understanding and changing their actions. Data must be presented in a meaningful way. Reports included benchmarking, monthly production reports, operator comparisons, individual operator reports, and bucket reports, all of which included comprehensive productivity and maintenance information. They included tables of data, line graphs, bar graphs, pie charts, and anything else the mine requested to help them understand what they were doing which impacted productivity or maintenance. Of critical importance was the fact that these reports were followed up with visits from dragline “experts” and trainers who helped all levels on the mine site interpret the reports and develop plans for “change”. In addition, all operators and supervisors attended off site courses which focused on team and individual understanding of the job they were doing.
The data was used to determine which digging techniques increased damage both from a global and an individual basis (comparisons were made both internally and externally). Effort was made to identify which operators needed help with productivity or maintenance or both. During the first 223 days of the program dig rate increased by 15% and boom stress decreased by 25%. In conclusion, the data and the analysis of it were not the reason improvements were made. Data was an integral part and improvements would not have been as significant without it. However, the real impact was the organisational culture which was created. The dragline was changed into a “learning group” with the following characteristics;
Competitive Advantage for a mine or organisation comes from operating at a higher productivity and lower cost than others. It should be seen as originating from doing a whole range of actions better than your competition. On this definition, the dragline studied here has definitely assisted this mine in achieving competitive advantage. The data was not the reason competitive advantage was gained but rather the most important strategic resource which itself was mined to extract the value. Change was the mine's most valuable strategic ability and enabled the knowledge from the data to add value to the mine.
There is a wealth of valuable mining data being produced around the world every day, however, mines are failing to benefit from it as they don’t have the ability to capture and meaningfully apply it. Through poor management of available data and the loss of personnel, the continuity of information acquired and knowledge applied to run mines efficiently is being broken. If not remedied, this will prove very costly in the long term.
Data by itself is just a mass of numbers - it needs to be analysed and assessed to extract value. However, mines must be wary of subjective analysis which is done for the benefit of another party rather than the mine itself. All too often the mining industry funds work by research groups and consultants which focuses on the process and how smart the process and people are. For knowledge to be valuable and to facilitate the innovation process it must be value-based, ie. it must provide bottom-line / profitability improvements for the mines. The key to this is the person pulling the levers or turning the steering wheel. This person has the ultimate control over what output is achieved. Therefore the mine must engage the operator / driver in the optimisation process. To do this they must have an intimate understanding of the information being provided through reporting of performance
The best way
to explain this is through a case study. While most mining equipment has
loggers generating data (and if your’s don’t then they should) the loggers on
draglines produce the most comprehensive data. A dragline with production
and maintenance loggers will have over 2,000,000,000 signals processed into
nearly 20,000,000 pieces of data, stored in databases every year for post
processing. (Is it any wonder that mines find themselves swamped by data?
)
In this case
study, the dragline is real and the results are real. Most importantly,
the lessons to be learnt can be applied to any operation and any piece of
equipment. This dragline historically operated at a production rate
better than average. When the maintenance logger was installed, a program
of improving productivity and reducing damage was initiated. The demand
for change came from a range of areas, including, the workforce, technology,
economics, competition, etc. The Mine Manager assumed the role of
“change agent” and sought the support of a range of internal and external
people who he perceived could help him. Not unexpectedly, resistance to
change came from individual and organisational sources. In overcoming the
resistance to change, the site focused on education, communication,
participation, facilitation, support, and negotiation.
A key part of this program was delving into the masses of data to provide specific and targeted reports to a range of people across the site. Remember the word “meaningful”. This is the key to operators and drivers understanding and changing their actions. Data must be presented in a meaningful way. Reports included benchmarking, monthly production reports, operator comparisons, individual operator reports, and bucket reports, all of which included comprehensive productivity and maintenance information. They included tables of data, line graphs, bar graphs, pie charts, and anything else the mine requested to help them understand what they were doing which impacted productivity or maintenance. Of critical importance was the fact that these reports were followed up with visits from dragline “experts” and trainers who helped all levels on the mine site interpret the reports and develop plans for “change”. In addition, all operators and supervisors attended off site courses which focused on team and individual understanding of the job they were doing.
The data was used to determine which digging techniques increased damage both from a global and an individual basis (comparisons were made both internally and externally). Effort was made to identify which operators needed help with productivity or maintenance or both. During the first 223 days of the program dig rate increased by 15% and boom stress decreased by 25%. In conclusion, the data and the analysis of it were not the reason improvements were made. Data was an integral part and improvements would not have been as significant without it. However, the real impact was the organisational culture which was created. The dragline was changed into a “learning group” with the following characteristics;
·
A shared vision,
·
Old ideas were discarded,
·
The dragline operation was seen as a system of
interrelationships,
·
People actually communicated with each other,
and
·
Personal interest was less important than
organisation interest.
Competitive Advantage for a mine or organisation comes from operating at a higher productivity and lower cost than others. It should be seen as originating from doing a whole range of actions better than your competition. On this definition, the dragline studied here has definitely assisted this mine in achieving competitive advantage. The data was not the reason competitive advantage was gained but rather the most important strategic resource which itself was mined to extract the value. Change was the mine's most valuable strategic ability and enabled the knowledge from the data to add value to the mine.
Graham Lumley - CEO of GBI Mining Intelligence
BE(Min)Hons, MBA, DBA,
FAUSIMM(CP), MMICA, MAICD, RPEQ
Labels:
data,
dragline,
GBI,
mining,
mining equipment,
productivity
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