Hydrocarbon Processing - January 2022 - 11

Reliability
HEINZ P. BLOCH, RELIABILITY/EQUIPMENT EDITOR
Heinz.Bloch@HydrocarbonProcessing.com
Try solving-instead of managing-equipment problems
Good managers manage people who
solve problems. Average managers keep
problems in check-i.e., they " manage "
problems but often allow these problems
to persist. An actual example involving
mixers will drive home the point.
Blaming the wrong part. It is not unusual
for mechanical seals in mixers to get
blamed for failures that were preceded by
lubrication-induced bearing distress. Such
was the case for years on about a dozen
large 200-rpm/160°F mixers with massive
rolling element bearings costing well over
$12,000 each. The owner company had
an anti-oil mist bias for reasons that defied
logic and disregarded the fact-based experience
of its leading competitors. Chances
are the company allowed itself to be influenced
by strong personalities assigned to
the maintenance department. Strong personalities
have been known to trust " gut
feelings, " anecdotes and mere intuition.
Their faith in these often takes precedence
over science and solid experience.
There is merit in managing facts.
Several facts were brought to the attention
of the owner company in the hope
that newly hired engineers would listen
to experience-based truths. Concentrating
on applicable science was advocated
by an expert when a clueless facilitator
reached out to him. The expert advised
against throwing more money at repeat
problems that others had solved 40 yr
ago. Much earlier, the expert had hoped
for an opportunity to tell site managers
that every type and style of rolling element
bearing can be lubricated with pure
oil mist. He would have explained why
the since-retired storyteller's anecdotes
were leading the company away from the
solution and deserved to be disregarded.
Eliminating repeat problems is always
better than wasting resources by managing
repeat problems.
The expert showed that well-designed,
small, fully closed (recirculating) liquid
oil spray modules and atomized oil
mist modules exist today. Either type of
$6,000 module being filled with a gallon
of ISO VG 100 (~90% PAO and ~10%
dibasic ester) synthetic lubricant would
have solved the problem a long time ago.
Again, it goes without saying that managing
true problem-solvers adds permanent
value, whereas managing problems that
continue to drag on can do serious damage
to a commercial entity.
When asked to first discuss greaserelated
matters, the expert made the following
points:
* Lube optimization at the prevailing
temperatures does not favor costly
PFPE-PTFE greases. Other properly
applied greases will also work.
* No type or style of greased bearing
will live long when grease reaches
only some, but not all, of its
rolling elements.
* Successful use of PFPE-PTFE
greases at this site would require
fully sealed bearings.
* Sealed bearings with PFPE-PTFE
fill have an anticipated life of 10 yr.
* Non-shielded (open) bearings
with properly applied shear-stable
premium electric motor (EM)
synthetic greases would survive, if
(properly) regreased every 6 mos.
* Timed, pressurized grease injection
is possible, as is directed (aimed)
pure oil mist application with riflebored
reclassifiers designed for
slow speed bearings.
* The best available bearing protector
seals should be used. Best available
implies using styles with diagonallymoving
O-rings contacting
generously sized contoured-surfaces.
* Liquid oil pumparound
(recirculating oil) modules of the
standard type and style used for
pressurized dual mechanical seals
would also solve the problem.
* Experience captured elsewhere
would be helpful in any comparison.
We will never know which option was
ultimately implemented by the owners of
this problem. However, it is fair to assume
that reading one or two recently published
books and implementing any of these
time-tested options would have saved the
owners millions of dollars.
Grooming motivated learners. There
is an important lesson to be learned here:
problem solvers start out as motivated
learners who become value-adders by reading
and absorbing fact-based books. They
should be expected to attend well-focused
and wholly experience-based training sessions,
thereby acquiring knowledge and
becoming professionals who rely on factbased
science. Acting on a " gut feeling "
and then wasting time on unproductive
experimentation has no place in situations
where the achievements of the competition
can be summarized as consistently
safe and reliable run-length extension.
Hopefully, the mixers' owners will get
to the point where its managing personnel,
irrespective of actual job function,
add value by solving problems instead of
merely managing problems. To the extent
outside facilitators are asked to assist in
root cause analysis, a common-sense approach
would be to enlist facilitators who
possess first-hand knowledge of bearings
and optimized lubrication. Choosing
one's facilitator wisely would accelerate
arriving at fact-based solutions.
HEINZ P. BLOCH resides in
Montgomery, Texas. His
professional career commenced
in 1962 and included long-term
assignments as Exxon Chemical's
Regional Machinery Specialist
for the U.S. He has authored or
co-written more than 780 publications, among them
24 comprehensive books on practical machinery
management, failure analysis, failure avoidance,
compressors, steam turbines, pumps, oil mist
lubrication and the just released, " Optimized
Equipment Lubrication, " (DeGruyter, Berlin/Germany,
ISBN 978-3-11-074934-2). Mr. Bloch holds BS and
MS degrees (cum laude) in mechanical engineering.
He is an ASME Life Fellow and was awarded life-time
registration as a Professional Engineer in New Jersey.
Hydrocarbon Processing | JANUARY 2022 11

Hydrocarbon Processing - January 2022

Table of Contents for the Digital Edition of Hydrocarbon Processing - January 2022

Contents
Hydrocarbon Processing - January 2022 - Cover1
Hydrocarbon Processing - January 2022 - Cover2
Hydrocarbon Processing - January 2022 - Contents
Hydrocarbon Processing - January 2022 - 4
Hydrocarbon Processing - January 2022 - 5
Hydrocarbon Processing - January 2022 - 6
Hydrocarbon Processing - January 2022 - 7
Hydrocarbon Processing - January 2022 - 8
Hydrocarbon Processing - January 2022 - 9
Hydrocarbon Processing - January 2022 - 10
Hydrocarbon Processing - January 2022 - 11
Hydrocarbon Processing - January 2022 - 12
Hydrocarbon Processing - January 2022 - 13
Hydrocarbon Processing - January 2022 - 14
Hydrocarbon Processing - January 2022 - 15
Hydrocarbon Processing - January 2022 - 16
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Hydrocarbon Processing - January 2022 - 18
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Hydrocarbon Processing - January 2022 - 40
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Hydrocarbon Processing - January 2022 - 81
Hydrocarbon Processing - January 2022 - 81A
Hydrocarbon Processing - January 2022 - 81B
Hydrocarbon Processing - January 2022 - 82
Hydrocarbon Processing - January 2022 - Cover3
Hydrocarbon Processing - January 2022 - Cover4
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