A Picture is Worth a Thousand Words - J.R. Simplot Applies
Straightforward Proactive Oil Analysis to Remain Competitive
Sharon H. Dory and Art Durnan, J.R. Simplot Company www.noria.com
Posted 11-10-03
Over the last decade no industry has been immune to the demands
of an increasingly competitive business environment. To compete
globally, companies have had to boost product quality and
reduced delivery costs. J.R. Simplot is an example of a company
that has applied these quality practices to equipment maintenance
and lubrication management using oil analysis.
J.R. Simplot is a private food processing and agricultural
company, 12,000 employees strong. The J.R. Simplot phosphate
mine, located near Jackson Hole, WY, is thought to be the largest
high-grade phosphate mine in the western USA.
Phosphate, a primary constituent of fertilizer, is mixed into
a slurry after it is mined and pumped at 3300 psi (about 225
Bar) for 87 miles to the processing plant where it is used
to make fertilizer. Due to the competitive nature of the fertilizer
market, the mining of phosphate is particularly sensitive to
production economics. Phosphate ore represents as much as 20-30%
of the cost of fertilizer. Therefore, the costs to extract
and deliver the ore represent a major portion of the total
cost to produce fertilizer.
Equipment maintenance represents 30-40% of the mine’s
total operating costs (Figure
1). The mining industry has historically
accepted these high maintenance costs as normal, but the team
at J.R. Simplot believed that they can be managed, adding substantial
profits to the bottom line. The mining industry has a saying: “Good
deposits make poor miners,” so “Poor deposits make
good miners.”
And while J.R. Simplot’s Wyoming mine is considered
high-grade, the maintenance team decided to not be complacent
regarding maintenance.
Benchmarking Shows the Way
Mobile equipment forms the core of the phosphate mining operations.
The fleet consumes 70% of the company’s total maintenance
budget. Of this budget, a large portion is consumed by haul-trucks
that receive ore from a shovel and transport it for unloading,
processing and pumping. New haul-trucks cost about $1.5 million
and about $100 per hour to operate, 50% of which is maintenance,
particularly engine maintenance (an engine rebuild costs
between $130,000 and $160,000).
Benchmarking the mine’s maintenance costs against other
phosphate open pit mines alarmed the maintenance team. They
found sizable gaps between the mine’s performance and
the industry’s best practice. Numerous improvement opportunities
were discovered. Increasing the life of the haul truck diesel
engines was one of those discoveries.
The original equipment manufacturers (OEM) conservatively
suggests that the engines be rebuilt every 15,000 operating
hours. Prior to the new maintenance initiatives, Simplot decided
to reduce the OEM’s recommended interval to 14,000 hours
to avoid the risk of catastrophic failures. With a focused
effort, the team believed they could substantially increase
the mean-time-between-rebuild on the diesel engines and put
a sizable amount of profit into the company coffers.
A Common-Sense Approach to Lubrication Excellence
The team recognized that poor lubrication management is a primary
root cause of engine failure. They created a strategy to
make lubrication management changes called the “senior
engine program,” to help extend engine life.
Lubricant Upgrade. The team upgraded to API Service Classification
CH4 lubricant, which is formulated using Group II base-oils
and a premium additive package. Lubricants had been purchased
from the lowest bidder, with a casual position on lubricant
quality. By specifying the enhanced quality product, drain
intervals were extended from 250 to 350 hours and filters began
to last longer. While the cost of the lubricant is 30% higher
on a per-gallon basis, the total cost to lubricate the engines
decreased. In addition to the benefits derived from extended
drain intervals and longer filter life, secondary benefits
have also contributed to the profitability of the change. For
example, labor costs have been reduced.
Filtration Upgrade. Machines with clean oil last longer. Engines
are no exception. The maintenance team decided to upgrade to
higher quality filters. They examined the Beta Ratings (particle
capture effectiveness) of several available offerings in the
market and selected the one most suited for their requirements.
Contamination control was achieved by upgrading full-flow filtration
and adding sidestream filters. Contaminant exclusion was improved
with upgraded air filters.
Oil Analysis. In 1992, the mine started performing oil analysis.
In the early days, oil analysis was performed because they “felt
it should be done,” not because they believed that measurable
benefits would be generated. At that time, the program was
typical; samples were drawn and submitted for analysis and
the results were filed away. When a new fuel and lubricant
contract was issued, the mine received an oil analysis trending
software program and they became more serious about oil analysis.
Samples were then drawn and analyzed at each oil change, which
occurs every 350 hours, or about twice a month.
The team soon discovered that their ability to predict engine
failures with elemental spectroscopy trend analysis was limited.
Abnormal conditions produce wear too large to detect with
conventional atomic emission elemental spectroscopy. They
supplemented the technique by back-washing filters and then
analyzed the debris with elemental spectroscopy whenever a
sharp increase in wear metal (iron, copper, aluminum, chromium,
lead) appeared. ...
... For “senior engines,” those that reached 15,000
hours, elemental spectroscopy is supplemented with large particle
oriented test. Particle count is performed to quantify the
large particles in the oil. Also, at the time of an oil and
filter change, the debris that is collected in the filter is
back-washed, deposited on a patch, viewed under a microscope
and digitally photographed. The particles are evaluated based
upon size and shape. If an engine is generating great numbers
of large wear particles, its life is assumed to be limited
and it is scheduled for over haul.
Other system improvements included keep-full systems, variable
speed fans, long-life coolant and upgraded fuel filters. In
addition to oil analysis, regular inspections were made to
assess the condition of the machine.
The Results Are In
The senior engine program has proven effective and very profitable
for the J.R. Simplot company. Previously, the engines were
rebuilt at an average life of 13,075 hours. They have increased
the average number of hours between engine rebuilds to over
18,000 hours
(Figure 3), a 37% increase! The amortized rebuild
costs for the engines have dropped from $8.26 to $5.68 per
operating hour (Figure 4); that equates to an annualized
cost reduction of over $15,000. Because this is a maintenance
cost, the money saved goes directly to the operating profit
line. All the engines in the senior engine program have shown
life extension except for engine number 1393, which failed
due to human error. The team’s goal is to achieve a
mean-time-between-rebuild of 25,000 hours. Nearly doubling
engine life will cut the annualized rebuild cost in half
to about $25,000.
The team’s unique approach to oil analysis has enabled
them to rebuild engines on condition, through the application
of patch microscopy analysis. In addition to getting all the
life the engine has to offer, the advance warning provided
by oil analysis allows for smart maintenance scheduling. The
photomicrograph pictured in Figure
2 show a quadrupling in
wear particles from the previous sample. The team knew when
this engine was a candidate for rebuild.
The team photographed components from the tear-down of an
engine that was rebuilt at 18,000 hours because oil analysis
signaled excessive wear. As predicted, several components showed
evidence of excessive wear. The bearing in Figure
5, for example,
indicated severe spalling. As one might expect, not all components
were worn out, but sufficient damage was visible to confirm
that the right decision had been made. Proactive measures to
manage engine life delivered an extra 5,000 hours of operating
life, while oil analysis indicated the engine had hit the end
of the line.
Conclusions
The maintenance team at J.R. Simplot’s phosphate mine
near Jackson Hole, WY has proven that smart equipment maintenance
can put money on the bottom line, and that good lubrication
management with oil analysis plays a vital role. The team’s
senior engine program is the epitome of simplicity. When machines
are pushed beyond proven time limits, they receive more detailed
health monitoring using oil analysis. When the machine provides
a visual indication that it is shelling out wear debris, action
is promptly taken. The team’s efforts increased the value
of J.R. Simplot’s competitive position, improved profits
and shareholder wealth and gave the maintenance team much to
celebrate.
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