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NuclearPlantJournal.com Nuclear Plant Journal, March-April 2016
Achieving Long...
The Zephyr
®
Advanced Acquisition
System for steam generator inspection
system is one.
As part of plant maintenance
requirements, plants have to inspect
every single tube of the steam generator
with eddy current. This has been typically
performed with what we call a Bobbin
probe, which is an eddy current coil
probe that goes through the tubes. That
probe is pushed through the tube using
a hard probe cable and then pulled back
to acquire the data. Previously, this was
done at constant speed and it took just as
long to push the probe through the tube
as it would to pull it back. Because of the
thickness and rigidity of the probe cable,
you can’t get all the way over some of the
tight U-bends. When this was the case,
the inspection would require entering
the tubes from both ends of the steam
generator to complete the inspection.
Our
new
Zephyr Advanced
Acquisition System is an air-assisted
drive probe, which has a smaller, more-
flexible almost wire-type cable. This
improvement allows us to push the probe
through the tubes with our variable speed
computer control at three to four times
the speed of previous inspections. The
probe goes all the way through the tubes
very quickly, and then we pull the probe
back all the way around the tube to collect
the eddy current data. Since the Zephyr
probe is more flexible, it is capable of
covering the tightest u-bends. You don’t
need to enter both sides of the tube to
collect the data. The increased insertion
speeds and elimination of entering tubes
twice has allowed us to reduce the time to
complete steam generator inspections by
30% to 40%. Additionally, the life of the
probes is much better. We get up to 45%
better wear on the probes due to its design
and the reduced forces on the probe from
the air assist. There is also much less
contamination on the probes, meaning
less contaminated waste is generated
from the inspection process. In fact, there
is a 50% reduction in radioactive waste.
We’ve been very successful with this
technology to reduce steam generator
inspections by as much as 2 to 3 days on
each outage. This schedule savings has
contributed to 22 hours of critical path
savings.
Another technology-driven inspec-
tion technique that we’ve rolled out in the
last few years is non-destructive examina-
tion (NDE) using phased array ultrasonic
technology. This inspection technique
can be used during inspections of reactor
vessel or balance-of-plant components. It
allows for a much more accurate image
of the weld or component being inspected
– like a three-dimensional viewing angle.
Specialized techniques such as phased
array NDE help to verify the integrity of
the component while performing the in-
spection service in less time and at lower
radiation dose levels.
9.
Describe any other highlights of
Westinghouse inspection technology?
There are two things about inspection
technology that are important to us.
One is the ability to gather
high-quality data while our workers
receive the least amount of personnel
exposure to radiation, which is what the
Zephyr Advanced Acquisition System
provides. With the sealed delivery
system that Zephyr technology employs,
contamination remains in the steam
generator, significantly reducing platform
dose. Because of the improved probe life
with Zephyr, it reduces the number of
times platform workers are intimately
working with the components to change
probes. As a result of the Zephyr
technology improvements, personnel
dose has been reduced 65%.
But the other consideration with
inspection technology is analyzing the
data. You have all that data coming
through all these sensors, yet the speed
of the acquisition is only as good as the
speed of the analysis, because you still
have to look at the data. If you have to
do that manually, then you need multiple
people, and it takes hours.
To rectify that, we now have
automated our data analysis with what
we call our TITAN™ Single Pass Auto
Analysis program, which is our total
integrated tube analysis system.
This technology provides a combina-
tion of multiple analysis techniques and
integrates the results from those multiple
techniques. With the TITAN system, in-
stead of having multiple analysts look at
every single line of every single piece of
data, our computer programs will analyze
all of the data using two different meth-
ods, such that they are verifying each
other. Any potential areas of concern are
identified and a senior analyst will review
the data and determine if the indication
requires additional analysis or action.
This automated method has allowed us
to reduce the number of analysts on site,
reduce the opportunity for human error,
reduce the amount of cost to our utilities,
and reduce the time it takes to perform
the analysis.
10.
Does Westinghouse have the
capability to receive a forewarning, that
a reactor coolant pump is in trouble,
or maybe a steam isolation valve needs
attention. Do you get an advanced
warning before it really breaks down?
Yes, it is known asBigDataAnalytics.
Using certain sensors and monitors which
we can place on critical pumps, valves
and motors in the plant, we are able to
receive information that is broadcast back
to the Westinghouse OCC. From there,
we can take a look at how the plant is
actually operating during that cycle and
then provide some diagnostic input as
to which pumps, valves or motors need
maintenance, and in some cases which
valves don’t need maintenance, because
if you have a maintenance plan that has
X amount of valves in it, maybe half of
those don’t actually need maintenance.
So we can assist in decision-making with
data about where to spend maintenance
efforts wisely. We’re just beginning to
roll this out now.
11.
How do you ensure that the radiation
dose in an outage is kept to a bare
minimum?
The Interactive Work Management
System is one example; I don’t have to
have a person in there right on the pump
Zephyr Probe.
