Hydrocarbon Processing - April 2022 - 26
Maintenance and Reliability
haps not enough oil). Why was there insufficient
oil? Was it because the constant
level lubricator had not been refilled?
We will never know how the next
" Why " would have been phrased, so we
will leave it at that. We would venture to
guess that " slightly off-horizontal shaft
centerline, " " oil ring eccentricity outside
allowable range, " and " OEM design allowed
oil to get trapped behind thrust
bearing, " would not be listed as likely
root causes.
Modern and consistently effective
methods will be needed to achieve the
goal of optimally conducting best available
troubleshooting and failure analysis
in today's highly competitive work environment.
Investigate them and invest in
the best.
NOTES
FIG. 4. OEM drawing of bearings with trapped oil. Drain holes are important.
tion of the pump manufacturer, we were
told that, although the pump manufacturer
had neglected to show drain holes, the
shop always provided these drain holes.
Well, as a wise and observant reliability
manager in Texas City said in 1980,
" When it is all said and done, more will
have been said than done. " That truism
has been true for centuries and was correct
in this instance. Accordingly, our recommendation
is to trust, but verify. In the
great majority of cases, not only is there
more value in verifying than in trusting,
but it will also cost less.
Experience-based training courses
will add value. Whenever failure analysis
and troubleshooting are called for, the
trained analyst insists on collecting failed
parts, measuring and recording dimensions,
and run-outs of rotating components.
Suspicious wear patterns should
be photographed.
The above examples represent details
of closely monitored parts, both new and
failed or defective. Thorough analysis is
especially important when there is evidence
of bearing overheating. Contributing
and causal factors can be of great importance
and will require both technical
knowledge and the application of structured
analysis. A formal training course
in systematic failure analysisa
will go a
long way towards uncovering and eliminating
costly repeat failures. Downtime
is prevented and money will be saved by
26 APRIL 2022 | HydrocarbonProcessing.com
learning (and later implementing) tested
approaches that bring the right focus to
modern equipment troubleshooting.
Indeed, the culmination of equipment
failure analysis involves motivated course
attendees. An experienced instructor will
assist them as they contribute to very
comprehensive custom troubleshooting
tables. The content of these tables represents
an expansion of the original equipment
manufacturers' (OEMs') tables into
territory that the OEMs may have overlooked
for years. We know of instances
where vendors viewed expanded troubleshooting
tables and/or the use of oil mist
lubrication as the original sin, a " sin " resulting
in shrinking spare parts sales. We,
however, cling to the belief that good marketing
decisions may result in unusually
reliable pumps and other fluid machines
that capture premium profits and enhance
vendor reputations. We believe that
a good reputation will more than make up
for reduced spare parts sales.
From the " 5 Whys " to modern methods
of failure analysis. The " 5 Whys "
method of defining failure causes predates
the training course in systematic failure
analysisa
a Equifactor®
LITERATURE CITED
1
Bloch, H. P. and F. K. Geitner, Machinery failure analysis
and troubleshooting, 4th Ed., Elsevier Publishing,
Oxford, UK, and Waltham, Massachusetts, U.S.,
2012.
2
3
Perez, R. X. and H. P. Bloch, Pump wisdom, 2nd Ed.,
John Wiley & Sons, Hoboken, New Jersey, U.S., 2021.
Bloch, H. P., Optimized equipment lubrication, oil mist
technology, and standstill preservation, 2nd Ed., De
Gruyter Publishing, Berlin, Germany, 2021.
MARK PARADIES has 42 yr of
experience in high reliability
organizations, process safety,
equipment operation and
maintenance, incident investigation,
and root cause analysis. His career
began as a leader in Admiral
Rickover's Nuclear Navy (where he earned Engineer
Qualification). He also worked for DuPont in the areas
of process safety, human factors and performance
improvement management before he started System
Improvements in 1988. Mark was one of the
co-creators of the TapRooT® System and worked
with Heinz Bloch on the original development of the
Equifactor® Troubleshooting Techniques. He has a
BS degree in electrical engineering and an MS degree
in nuclear engineering (with an emphasis on human
factors), both from the University of Illinois.
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 United States. He has
by several decades; however,
suppose it had been attempted in one of
our earlier examples involving a failed
pump bearing. The analyst would have
started by asking: Why did the bearing
fail? Chances are that someone offered an
answer involving the lubricant (e.g., perauthored
or co-written more than 780 publications,
among them 24 comprehensive books on practical
machinery management, failure analysis, failure
avoidance, compressors, steam turbines, pumps,
and the just released Optimized lubrication, oil mist
technology, and standstill protection.3
He holds BS
and MS degrees (cum laude) in mechanical
engineering and is an ASME Life Fellow with life-time
registration as a Professional Engineer in New Jersey.
http://www.HydrocarbonProcessing.com
Hydrocarbon Processing - April 2022
Table of Contents for the Digital Edition of Hydrocarbon Processing - April 2022
Contents
Hydrocarbon Processing - April 2022 - Cover1
Hydrocarbon Processing - April 2022 - Cover2
Hydrocarbon Processing - April 2022 - Contents
Hydrocarbon Processing - April 2022 - 4
Hydrocarbon Processing - April 2022 - 5
Hydrocarbon Processing - April 2022 - 6
Hydrocarbon Processing - April 2022 - 7
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Hydrocarbon Processing - April 2022 - 88A
Hydrocarbon Processing - April 2022 - 88B
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Hydrocarbon Processing - April 2022 - Cover3
Hydrocarbon Processing - April 2022 - Cover4
Hydrocarbon Processing - April 2022 - GP-1
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_200905
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200904
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200903
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200902
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200901
https://www.nxtbookmedia.com