The following photos show how we attempt lubrication
excellence via contamination control and oil analysis,
focusing on our anaerobically digested sludge dewatering
centrifuges. I am one of the mechanical maintenance 'specialists'
that is responsible for maintaining the assets necessary
for providing treatment of domestic, commercial, and pre-treated
industrial wastewater flows of the City of Ft Collins,
that are returned to the environment, meeting and often
times exceeding, EPA requirements. I am specifically responsible
for all scheduled maintenance including machinery lubrication
and have incorporated many proactive steps to attempt
to obtain lubrication excellence through condition monitoring.
The first photo is that of forced oil-lubrication from
an oil reservoir and a gear-rotor pump, to one of two
double-row spherical pillow block roller bearings (one
on each end) of a section of the machine itself. These
machines costing over $500,000 in capitol each. (we have
two of these). A 300hp AC variable primary drive motor
spins a bowl sheaved to a speed of 2800 rpm. A 100hp variable
back-drive motor spins a sludge scroll, internal of the
bowl, holding back solids to a controlled discharge. Although
this is a small capacity reservoir (15 gallons - ISO VG
46 turbine oil) the system is vital to the operation of
Here is a close-up of the reservoir, showing the installation
of a pressure-type oil sampling valve, located before
on-line filtration (Beta 2/75 @ 6/17 micron respectively)
of the reservoir oil. Oil samples are also taken on this
machine directly downstream of each pillow block bearing,
prior to the oil returning to the reservoir.We have retrofitted
the original reservoir cap with a dessicant breather.
The reservoir lid has been re-gasketed to better seal
the perimeter from surrounding contamination. This is
all action taken directly from results of our oil analysis
This picture shows our portable off-line Parker Guardian
GT-4 kidney-loop filter (beta 2/20/75 @ 3/7/10 micron
respectively), in use during scheduled down-time, improving
oil cleanliness when our ISO4406 particle counts rise
to cautionary levels. The kidney-loop suction is temporarily
plumbed from the reservoir drain, and discharges to the
opposite side of the baffled reservoir.
This is a shot of the entire machine.
This photo shows modifications to original equipment
that has allowed strategic collection of oil samples directly
off of each pillow block bearing. At this point, the oil
is under gravity flow back to the reservoir.
The pressure-type sample valves do not work in this application
so samples are collected from a ball valve, nipple and
pipe cap arrangement. Originally, there was a 2"
pipe plug at this point. You can also see the installation
of dessicant breathers. Experience proved that these had
to be raised above an oily residue that would enter the
silica gel media of the breathers. OEM originally had
1" x 6" pipe nipple vents with 2 - 90 degree
bends pointing the vent downward and it terminated to