The Hidden Cost of Oil Changes
Ken Brown, Utility Service Associates, www.noria.com
Posted 9-27-03
Proper lubrication is an essential maintenance function and
changing oil is one aspect of the process. Unlike changing
the oil in your car based upon time or miles, oil changes
for industrial equipment should be based on need where no
other practical solution to restore proper lubrication is
available. Too often, we schedule an oil change to rectify
a contamination problem or when excessive wear is detected.
In neither case is the oil change a certain correction of
the root cause of the problem, and it wastes good money and
further stresses the environment with hazardous waste.
There are many hidden costs associated with oil changes that
are often not taken into account when the action is scheduled.
For example a very simplistic approach might only consider
labor to change oil + disposal costs + cost of new oil. But
there are other more significant hidden costs such as downtime,
administrative purchasing costs, storage, handling, testing
and spills, often accounting for many times that of the oil
alone. For example, damage to the machine during a change can
occur for the following reasons:
• Adding the wrong oil.
•
Over/under-filling the sump or reservoir.
•
Cross threading a drain plug.
•
Starting the equipment dry (it happens).
•
Introducing contaminated oil
Over the operating life of the plant, there will be oil spills.
Like fires, they happen, but the degree to which you are prepared
often determines the extent of the damage. The consequences
of spills can range from the need for solvents and cleaning
agents to remove oil from equipment and walkways, to replacing
pavement or digging up soil, to major expenses and adverse
publicity if the oil gets off site and into local waterways.
Costs might range from hundreds of dollars to millions of dollars
depending, of course, upon the nature and severity of the occurrence.
Oil spills can occur at all phases in the oil change process,
including the following:
• In storage
•
During transport to the equipment
•
While draining the old oil
•
While adding the new oil
•
When disposing of the used oil
It is important to know your options when it comes to lubrication,
and the real costs associated with each option, not just for
oil changes but also for costs like re-engineering with better
seals or filtration equipment. Facts and information reduce
uncertainty and improve the quality and profitability of decisions
about lubrication. Some of the following activities can, if
well thought through, yield tremendous savings to the organization:
• Test oil so that it is only changed when required.
•
Use the correct oil for the application.
•
Filter oil so it is not changed just because of particulate
contamination.
•
Purchase good products, not allowing mixtures or cocktails.
•
Use extended-life lubricants.
•
Upgrade seals to reduce leaks and contaminant ingress.
•
Provide staff with proper training and oil change equipment.
The Search for Hidden Costs
Like most activities, changing oil is not as simple as it seems
on the surface. There are supply personnel, planners, schedulers,
coordinators, health and safety staff and procedures involved
in the process. These behind-the-scenes activities add "hidden" overhead
cost to the oil change process that is often difficult to
clearly define. Maintenance activities have to do with preventing
or correcting wear of lubricated surfaces. The behind-the-scenes
support often costs multiples of the simple cost to perform
the maintenance activity itself.
Other costs such as availability, environmental compliance
and risk-based costs need to be factored into the equation
also. Below is a discussion of some of these costs as they
relate to a power plant. Also, estimated costs for performing
an oil change on a small system are identified in each section.
The factors and figures may vary for your industry, but based
upon the discussion, you should be in a position to make appropriate
revisions.
Availability Cost - If the oil is being changed, the equipment
is unavailable, not for just the time to change the oil, but
from the time it is isolated until the time isolation is removed.
The impact of unavailability is estimated to be one day or
0.3% of the annual usage because attempts to get a dollar value
have not been successful, mainly because the cost depends upon
where in the production cycle the equipment is located. When
a machine cannot be shutdown 'just' for an oil change, this
can still be done in many cases by bleeding and feeding. Using
this approach, availability costs are lowered, but oil and
labor costs are increased. Of course, this type of activity
always creates some risk that lubrication will be compromised.
Estimated as $200 per change.
Paperwork and Permit Costs - Generating permits, tracking,
verifying and inspecting work all cost money. Even locking
out an electrical panel takes time. Multiple trades may also
be required to complete the task. Estimated as one hour of
labor, or $27.
Labor and Benefits - The hourly pay is just part of the cost
for labor. Benefits and corporate costs to administer human
resources functions must be included in the total. Estimated
as 1.5 times the hourly rate times the number of direct hours
to complete the task.
Ancillary Activity Labor - Estimates of the time required
to complete the oil analysis task should account for ancillary
activities such as wait time, travel time, tool and material
collection.Costs can range from two, to as high as eight times “wrench
time.”
Supervision - Supervisory tasks always accompany the oil change
job. Include time to issue work orders, assign and schedule
the work and monitor activities in the estimate. This involves
supervisors, maintenance support and maintenance planners.
For example, each crew might have a lead hand and there will
be a supervisor for every so many maintainers. Estimated as
20% over and above direct labor costs.
Oil Disposal Costs - This is the cost to pay an independent
trucker and waste disposal company to collect and properly
dispose of non-radioactive and non-chlorinated waste oil. Radioactive
waste can be about $2,000 a drum. Alternatively, if it is used
as fuel on site or for other purposes there might be a value
assigned to the waste oil, but there would still be costs to
move it around and if being burnt there are usually regulatory
guides that have to be followed. Estimated as $0.50 per gallon.
Transfer Costs- Transfer burden should consider costs for
temporary storage site, safeguarding, moving to the shipping
truck or to a secondary site and, finally, transfer to the
loading dock or long term storage. Estimated as one hour, or
$27.
Lab Costs - Laboratory space and equipment, labor and tracking
costs associated with sampling all used drums, and the costs
for testing such as for radiation, PCB's, chlorine, glycol,
water, metals and/or solvents in the waste oil as required.
This value may vary depending upon local compliance requirements.
Estimated as $100 per drum, or $2 per gallon.
Solid Waste - When oil is changed solid waste will also be
generated that should be included in the estimate. This includes
gloves, filters, wipes, solid absorbents, plastic bottles and
hoses for sampling and the empty oil drums. Estimated as $25
per change.
Liquid Waste - If the oil has been allowed to degrade too
far there will be liquid waste in the form of solvents or flush
fluid for which disposal is required. This factor is very relevant
to cost benefits associated with proactive maintenance and
the use of long-life products. Estimated as $25 per change.
New Oil - The list price for new mineral oil is about $5.00
per gallon. Bulk steam turbine oil costs less while hydraulic
oil and gear oils will cost more. In comparison, synthetic
oils are significantly more expensive. For example, some fire
resistant synthetic fluids cost $28 per gallon. Estimated at
cost times volume.
New Oil Overhead - These costs include inventory or carrying
charges and the costs of storage areas. Costs for the heated
storage is taken to be $1/year/cubic-foot, although it would
be higher because oil storage and local oil rooms require extra
fire protection, venting and grounding. Further, a typical
supply crib requires staff. There can also be carrying charges
for stock. Estimated as $100 per drum or about $2 per gallon.
Purchase Orders - Several costs are incurred during the purchasing
process. These include preparation and submission of the request-for-bid,
review of available options, selection of successful bidder,
running credit checks, making payments, etc. Estimates for
this process range from $250 to $1500 depending upon complexity
and scope. Estimated as $400 per order.
Equipment Failure and Spills - Changing oil is an intrusive
maintenance action and there is some risk, as previously discussed.
It is expected that there will be at least one failure over
the life of the plant due to these risks with an estimated
cost of $100,000. This is considered conservative because it
assumes no outage results. Based upon a forty-year station
life, and an estimated 130 oil changes per year, the risk cost
is simply spread evenly at $20 per change.
Safety - Changing oils involves a number of potential safety
hazards, including slipping, skin contact and lifting associated
back injury. With regard to back injuries each 55-gallon drum
of oil weighs about 400 lb (180 kg) so that lifting devices
are usually required and are often not included in the cost
estimation. Estimated as $20 per change.
New Oil Testing - A new oil sample should be taken and analyzed
to verify that the correct oil was supplied and to baseline
for subsequent testing. The cost of this testing and all
aspects associated with it (data management, sampling consumables,
etc.) should be included in the cost estimate. The total
cost might include the cost of the testing, the labor to
take the sample, the cost of the sample bottle, the shipping,
the interpretation of the results and the record keeping.
Also, the practice of frequently changing oil can greatly
complicate used oil analysis. As Figure 1 shows, it is
extremely challenging when make-up oil alone is added to the
tank.
If part of a large program, the associated costs of new
oil testing should be very low. Estimated as $100 per change.
The Bottom Line
To calculate the real cost of an oil change, one must add up
all the direct costs, the overhead costs and the implicit
risk-based costs. The actual "real cost" to change
the oil in a rather small system at a power plant requiring
5-gallons of oil (at $5 per gallon), two man-hours of direct
labor and a purchase order to obtain the oil is $988.70 ALMOST
40 TIMES THE COST OF THE NEW OIL! While a significant part
of the total cost lies in the cost of issuing a single purchase
order, there are occasions where this occurs. ...
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