Efficient Plant Nov./Dec. 2022 - 20

feature | lubrication solutions
Lubrication policy elements
oil-analysis tests should be performed; and
what targets or limits are appropriate.
By defi nition, lubrication PMs that are
Lubricant
verifi cation
Lubricant
quantity &
frequency
Inspection &
application
procedures
Equipment
modifi cation
plans for
maintainability
Oil analysis
design & test
slates
Oil health &
cleanliness
targets
A lubrication policy defi nes the engineering behind precision lubrication and contains the items in the
illustration. Images courtesy AMMRRI/Generation Systems
lies not in the taxonomy outlined in the
standard, but rather how many companies
choose to deploy asset hierarchy in their
maintenance-management systems.
Because most systems are set up to
account for MRO costs, many companies
do not build their hierarchy below levels 6
or 7, which might be defi ned as the machine
train (conveyor) or sub-assembly (drive).
What should be levels 7 to 9, which are
maintainable items (gearbox) and parts
(input shaſt bearing), are usually defi ned as
fi elds, associated with the lowest level 6 or
7 hierarchy. While this may seem a subtle
distinction, this practice can lead to some
real defi ciencies when it comes to managing
lubrication PMs.
Consider the simple example of a pump.
At the machine-train level, level 6 refers to
the whole pump including the driver (in
this case the electric motor), the coupling,
and the driven component (the pump).
From a cost-accounting perspective, this
makes total sense when the only question is,
" how much does it cost to own, operate, and
maintain the pump? " It also makes sense
for maintenance tasks, such as alignment,
20 | EFFICIENTPLANTMAG.COM
for which the goal is to make sure that the
machine train is correctly aligned. But
lubrication tasks do not occur at level 6 or 7.
In fact, it could be argued that lubrication is
a level 9 activity.
Take our pump example. A pump will
have a least three and perhaps as many as
fi ve lubricated parts, including the drive and
non-drive end motor bearings; the coupling,
which may or may not be lubricated;
and the pump bearings that may share a
common bearing housing or be lubricated
separately. For other systems, such as circulating
lube-oil systems or hydraulics, the
situation is even more complex with dozens
of maintainable parts, each of which needs
to be lubricated, inspected, and/or sampled.
LUBE PM SETUP
To set up lubrication PMs, we fi rst need to
defi ne the lubrication policy for the asset.
Th e policy defi nes the engineering behind
" precision lubrication, " including which
lubricant to use; how much to apply; how
oſt en, where, and how to inspect or sample;
how to modify the equipment to insure
maintainability and fl uid cleanliness; which
built out of the lubrication policy need to
occur at level 9 of the asset hierarchy. Th e
drive and non-drive end bearings need to
be lubricated and may or may not use the
same or diff erent lubricants. Th e quantity of
grease to apply may be diff erent, depending
on bearing type. If the coupling is lubricated,
which grease should be used and how
oſt en should you re-pack? How should you
sample or inspect the pump-bearing housing
and what tests should be conducted?
Once these decision have been made,
the information needs to be codifi ed into a
series of unique PMs that need task details
(grease quantities) and procedural steps
that need to be scheduled as part of the
maintenance-management workfl ow.
In most maintenance-management
systems, PMs need to be assigned at a
specifi c level of the hierarchy. In a level 6 or
7 hierarchy, where should the lube PMs be
assigned? Th e functional location, machine
train, or neither? Also, where does critical
information such as lubricant quantity or
lubricant type reside?
While the answer may seem obvious-
defi ne the asset hierarchy down to the
individual maintenance part, e.g., drive end
bearing-the complexities that this would
create, not the least of which is having to
open and close literally tens or even hundreds
of thousands of lube PMs, make this a
less-than-desirable option.
Many companies solve the issue by creating
lubrication routes, which are a collection
of tasks that are in the same location,
scheduled on the same frequency, and use
similar tools (grease gun) or lubricant. Lube
routes are then issued against a functional
area (machine room).
But what about accountability and traceability?
What if one task out of a hundred
on a PM is not completed, perhaps due to a
NOV/DEC 2022

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Efficient Plant Nov./Dec. 2022

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