
Road to Gold
Hamilton Sunstrand quest to achieve UTC's Ace Gold Status
by Steven Piazza, Hamilton
Sunstrand (Winner
Uptime Magazine PdM Program of Year Award Best Ultrasound
Program for 2007)
This paper will be presented at
PdM-2008 - Predictive Maintenance Technology Conference and Expo
The maintenance aspect of our jobs would
be easy if we could have the advanced knowledge of machinery and
equipment failures. By closely predicting the life cycle of
parts and equipment it would be simple to schedule the repairs
and the replacement of equipment and manufacturing systems. As
we all know, accurate and timely scheduling team up to drive the
effectiveness and efficiency of our maintenance resources.
Unfortunately, the infant mortality of
components and the random losses of machine parts are the
leading failure modes affecting equipment reliability. Often
these losses are caused by human intervention through time based
“Preventive Maintenance” tasks and the simple act of production
cycles.
Many times these two failure modes
interrupt established schedules. This interruption is the key
source of reactive maintenance management. When this happens,
the facilities organization is thrown into a cycle characterized
by “failure, fix and failure, fix”. Organizations defined by
this mode of operation are likely treating symptoms with
band-aids and they are seldom able to put permanent solutions to
reoccurring problems. There has to be a better mode of
operation!
To combat unscheduled interruptions,
“Best Practice” companies use proactive maintenance techniques
to monitor the condition of their machinery and equipment. This
knowledge enables us to leverage our resources for required
maintenance through better scheduling. Better-controlled
schedules lead to improvements in up time and quality, while
minimizing safety and environmental incidents. This increased
plant reliability allows organizations to effectively reduce
work-in-process inventory while experiencing reduced indirect
maintenance costs.
We are fortunate that our plant
machinery, equipment, and systems are actually indicating their
respective operating conditions. Through the use of predictive
tools, maintenance organizations can learn how to baseline the
key operating characteristics of their equipment. Predictive
technologies such as vibration analysis, ultrasonic leak
detection, infrared thermal imaging, electric motor testing, oil
analysis, ball bar analysis, and precision alignment are all
leading edge indicators of overall equipment reliability.
Top business leaders are very aware of
the costs accompanying indirect head counts and budgetary
numbers. They also know that adding cost and passing it on to
the customer will not be tolerated in a globally competitive
market place. At the same time, each facility’s performance
expectations, both internally and externally, are on the rise.
We no longer have the latitude to add
cost by throwing manpower and other costly resources at
problems. We have to find ways to become effective in what we do
and drive efficiency in how we execute our responsibilities. As
maintenance professionals our task is to define the key
components of a piece of equipment or system, identify the best
technology to be used to monitoring performance under load,
collect data using the appropriate technology, benchmark that
data over time looking for change from a pre-determined
baseline, and finally investigate the cause of those changes.
For the past seven years, Hamilton Sundstrand has worked hard at
applying this methodology in a manner that could dramatically
affect the way we conduct business.
Hamilton Sundstrand uses ACE (Achieving
Competitive Excellence) methodology as its operating system for
the entire division. ACE is UTC’s unique quality initiative
whose infrastructure supports and sustains quality throughout
the corporation.
As Hamilton’s operating system, ACE
tools, like PdM, relentlessly drive its People, Processes and
Procedures, to eliminate the difference between results and the
desired outcomes of both Hamilton’s internal and external
customers. The system is powered by the disciplined application
of ACE tools for continued process improvements, problem
solving, and decision-making. It is the descriptor that confirms
our culture of continuous improvement and is based on facts
backed by data and focused on results leading to “World-class
performance.”
The process/methodology that has become
standard work for Hamilton Sundstrand and has been instrumental
in breaking this reactive cycle of repair, mirrors Six Sigma
Methodology (the DMAIC model). By identifying and implementing
five key process steps, Hamilton Sundstrand was able to
systematically start the conversion from the traditional
reactive maintenance management organization to a proactive
group. We began to use the ACE operating system and its tools to
manage our facilities organization as a business, like any other
operations group.
These five fairly simple steps have
become our cookbook approach to applying all the tools of TPM to
the assets that we are charged with protecting. This “standard”
approach includes:
1.
“Definition and Prioritization”
Key components are rated into three
categories (A most critical, B critical but covered by
redundancy, C least critical). During this process, we looked at
a number of different key performance indicators: asset history,
internal customer requirements, and standard maintenance
procedures. We compared them to OEM recommendations, OEM
manuals, and the constraints within the process itself. We came
to the realization that often times the performance of systems
common to multiple processes and operations became more critical
than individual or isolated assets. In our transformation, it
became critical for us to deal with systems and system
performance, instead of focusing on the life expectancy of
individual parts.
2.
“Measuring Performance”
We accomplished the second phase by
selecting the best PdM technologies for data collection. We
determine a specific route with established data collection
frequencies. Consistent and accurate vibration data collection
is the foundation of a successful vibration data collection
program. Minimizing variances in collection is critical for
accurate data analysis to occur. Vibration data is collected
completely from each machine comprised of driving
components and driven components. A complete set of data
consists of 3 measurement directions from each bearing location
(2 in radial and 1 in axial direction). Based on
bearing-specific measurements and machine design, multiple
measurements are incorporated, including but not limited to,
acceleration and velocity.
Data is downloaded at the completion of
a route and briefly reviewed to ensure data integrity and
imminent failures. Accurate vibration data analysis will provide
a measure of asset health. This in turn will lead to increased
reliability through early detection of machine faults. Once a
known baseline is set, we monitor the rate of change through
ongoing data collection.
3. “Analyze”
During the data collection process, we
are continually comparing data over time and watching collection
points move up the prioritization list. Trending of the
vibration amplitudes allows for the development of a rate of
progression, which facilitates the convenient scheduling of
repairs, prior to failure. The final assessment is based
on multiple measurements per direction and at each collected
location. Severity of the final recommendation will be based not
only on the vibration signature, but also on the rate of change
observed, with respect to historical trending. This disciplined
data collection and benchmarking change soon became our standard
mode of operation, as we started to see the development of
problems long before they became catastrophic losses. All
anomalies are prioritized on a scale from 1 (indicating the need
for immediate action) to 4 (no action is required and we will
just continue to monitor). When a collection point reaches a
level 2 or 3 and a change in performance has been noted, we
investigate that particular asset and analyze the causes for the
documented change.
4.
“Improvements”
Parts eventually do fail and the fourth
step in our five-step process addresses improvements. We
investigate all anomalies with detailed failure analysis and
robust, relentless root-cause analysis. In this step of our
predictive maintenance process, we concentrate on good trouble
shooting techniques, backed by measurable data that may come
from increased PdM data collection or by utilizing other PdM
technologies to incorporate synergies. When any improvements are
made, new baselines need to be reestablished to successfully
monitor the asset in the future.
5.
“Controlling”
The final step in this cookbook approach
deals with controlling the process. There is a lot of work done
up front in the first three steps of this cycle. The definition
of the system, identification of critical collection points,
subsequent measuring, and finally, analysis are really at the
heart of the process. With defined collection points,
established frequencies, set schedules for the collection of
data, and an easy-to-read prioritized report, we let the data
(and not emotions) lead us to opportunities that will prevent a
catastrophic loss. Regular monitoring assures us that we will
see change before it has a chance to detrimentally affect the
performance of an asset. With a good prediction, we have the
opportunity to plan and schedule our corrections, driving the
efficient use of resources.
Part of our UTC culture is to share best
practices. This cookbook approach has received much attention
throughout the Untied Technologies Corporation family. The most
frequently asked question by other facilities groups is, “How do
you (Hamilton Sundstrand) justify the resources and cost of this
much data collection?” While it is true that not every
collection point reveals an anomaly/opportunity, an analysis of
our data over the last seven years has shown that 10% of all
data points collected indicate some change over time. It is the
recognition of this change and the subsequent investigation that
leads to discoveries that under normal circumstances would not
have been given any consideration.
Many times, the repairs are cost
avoidance type issues that managers are hesitant to claim as
justified cost savings. From our experience we know, without a
doubt, that once a collection point starts to show change--if
left unattended--that component will fail.
So as the old adage goes…you
can pay now when the problem is manageable or you can pay more
later.