Rotating machinery commonly used in
various processing plants, such as centrifugal pumps and compressors,
reciprocating pumps and compressors, fans/blowers, steam turbines, and electric
motors.
Simple troubleshooting tables as advised
by OEM or decision trees are rarely effective in
solving complex, real-world machine problems. For this reason, the Petchem Skills
Consulting services( https://petchemskills.com)
offers a novel way to attack those machinery issues that can adversely affect
the safety, reliability and efficiency of plant processes. The methodology adopted
and being taught to the Reliability Engineering and asset management professionals
is not a rigid approach but rather a flexible and dynamic process aimed at exploring
process plant machines holistically in order to understand and narrow down the
true nature of the problem.
We train and guide maintenance and
machinery professionals and managers to better understand how to troubleshoot
process machinery in -situ i.e., in the field when machinery is
in the running condition. This we call it “Field troubleshooting” which means and involve operation and
maintenance engineers/ supervisors to ask themselves “Is My Machine running
OK”? using
the “who, what, when, where, why”
troubleshooting methodology.
To be successful, the field trouble-shooter
must be persistent, open-minded and disciplined. Once field data is collected,
an unbiased, logical approach to the finding is required to hone in on the most
probable source of an observed symptom (or symptoms). Without a comprehensive
and logical analysis of the findings, the investigator is only guessing, which
wastes valuable time and resources.
We know that Process machines
are critical to the profitability of processes. Safe, efficient and reliable
machines are required to maintain dependable manufacturing processes that can
create saleable, on-spec product on time, and at the desired production rate. As owner of the process
machinery, one must wish to keep equipment in serviceable condition all the
time.
One of the most challenging
aspects of a machinery professional or operator’s job
is deciding whether an operating machine should be shut down due to a perceived
problem or be allowed to keep operating and at what level of operation. If he
or she wrongly recommends a repair be conducted, the remaining useful machine
life is wasted, but if he or she is right, they can save the organization from severe
consequences, such as product releases, fires, costly secondary machine damage,
etc. This economic balancing act
is at the heart of all machinery assessments.
The primary purpose of the knowledge
and skills taught by us to guide help operators and machinery professionals
troubleshoot machines that are in a process service and operating at design process conditions.
Hence the definition of Field troubleshooting is
a process of determining the cause of an apparent machine problem, i.e.,
symptom, while it is still operating at actual process conditions.
Troubleshooting efforts tend to focus on a specific machine or subsystem, using
a proven body of historical knowledge. The body of knowledge may be in the form
of troubleshooting tables and matrices or manufacturer’s
information. Keep in mind that process machinery can only truly be tested and evaluated in
service and under full load, i.e., in- situ Very few testing facilities are available that can test a pump or
compressor at full process loads and with actual process fluids. Field
troubleshooting evaluates the mechanical integrity of a machine in process
service in order to determine if symptoms are the result of an
actual machine fault or a process-related problem.
Here are examples of
troubleshooting opportunities:
Example 1: Pump flow has
fallen well below its rated level.
Example2: Compressor thrust
bearing is running 10 °C hotter than it was last month.
Approach to be adopted by
field trouble-shooter :
1. The field trouble-shooter must
first ask: Do I fully understand the machine or subsystem that needs to be analysed?
If the complexity is beyond the trouble-shooter’s
abilities, he or she should get help. At this point, management may decide to
conduct an RCA analysis.
2. If the field trouble-shooter
decides to tackle the problem at hand, he or she should then ask: “Are the observed symptoms caused by a failing machine, a correctable
fault, or by undesirable process conditions?” If it is
a process related problem, changes can be made before permanent machine damage occurs.
If a fault is deemed to be correctable, then adjustments or minor repairs can
be made in order to quickly restore the machine to serviceable conditions. This
what is expected from the field trouble shooter
If the machine fails, either
a failure analysis or root cause failure analysis must be performed, depending
on the extent and cost of the failure.
