October 2010: T5
found indication that Bobbin could not.
The pictures at the right
indicate defects that were not found by the bobbin coil.
They are circ cracks, one circumferential and one
longitutinal in origion. The first one was found
on a normal test at an Internalionally known aerospace
contractor site in Los Angeles. This finding saved
the company close to $50,000! The next two were
know leaers that were not discovered by the bobbin, only
the T5! The third picture waas 1.5" into the tube
where the bobbin is ineffective.
August 2010: T5
reintroduced at EPRI Conference
T5 HyTec Probes along with VM Products reintroduced
the T5 probe with great success and interest. Dave
Brown of VM presented the latest technology and
advantages to a packed room. Many companies were
interested in buying as well as selling the probe to
their clients. We currently have a Canadian
company that is on board with handling sales in Canada.
We were very excited to have had the opportunity to
present our power point presentation since it was due to
a last minute opening in the schedule. For a copy
of this presentation click
HERE.
April 2009: T5 HyTec
shows promise as a tool for sizing ID pits
During an April inspection at a certain TVA fossil plant,
plugs were removed from a number of previously leaking tubes
for inspection with T5 HyTec. In each of these tubes,
through-wall cracks were expected at the tubesheet.
However, the T5 was able to rule out the presence of any
tubesheet cracks. Of course this means that the documented
leaks were from other defects. Also present in these
tubes were a number of ID pits which bobbin had sized in
the 60-65 percent range. A preliminary review of calibrated
T5 HyTec data from these same pits shows a number of pits
measuring at or very near through-wall (100%) depth.
March 2009: T5 HyTec
probes detect circumferential cracks at two more plants
T5 HyTec probes were recently deployed at a fossil power
plant in Maryland and at Limerick Nuclear Station in Pennsylvania.
In both cases, recent tube leaks had alerted the respective
utilities about the possible existence of cracks, yet conventional
eddy current techniques had been unable to detect any (i.e.
bobbin and AC3). In the fossil plant, the tubes were prime
surface (un-finned) tubes, while the Limerick tubes were
skip-finned. In both cases, T5 HyTec was able to suppress
the tubesheet expansion signals sufficiently to allow for
detection of cracks. Furthermore, at Limerick, T5 Hytec
was able to rule out the existence of suspected cracks at
skip-finned TSP intersections, which possessed a full .100"
diametral expansion! At the fossil plant, the crack
indications (multiple) were confirmed visually with a borescope,
while at Limerick, the crack indication was confirmed visually
(ID discolorations) and with a refrigerant detection device.
Future destructive examination is also possible for that
tube. The inspection vendors associated with these tests
were Heat Exchanger Systems (fossil plant) and Master Lee
Energy Services (Limerick).
February 2009:
Duck Creek Main Condenser
Inspection Update
"This is the best condenser inspection I've seen since
I began testing in 1979" says Doug Calender, ET Level III
for Young Technical Services. Using a T5 HyTec probe,
YTS has been able to detect previously undetectable circumferential
cracks at dented tube support intersections.
These calls have already been confirmed with pulled tube
destructive analysis.
Such detection will allow for accurate and focused repair decisions; something
that will extend the life of this aging heat exchanger.
January 2009: T5 HyTec
detects another missed leaker
After performing a complete eddy current examination
of a particular air conditioner in October, Dennis Hendricks
of K&L Services was disappointed to learn that the same
unit leaked a few weeks later. Dennis re-tested the
leaking tube in January with the T5 HyTec probe (the original
test had been conducted with a conventional AC probe).
The T5 Hyec easily detected the leaking defect, which was
located in the difficult geometry of the skip-fin transition
area (a dramatic tube expansion and wall thickness change
found in most air conditioners). T5 HyTec has restored
the customer's confidence in K&L's ability to reliably detect
and quantify structurally significant defects in their heat
exchangers.
January 2009:
T5 HyTec Probe chosen for Duck Creek Fossil Plant main condenser
inspection
Following a December feasibility study where T5 HyTec
detected circumferential cracks at dented tube support intersections
that were not detectable with other eddy current probes,
a T5 HyTec probe was chosen as test of record for a major
inspection (~7,000 tubes) which began January 29th.
The initial scope is 50% of the total number of tubes in
the exchanger, which are 1" X .049 admiralty brass and 1"
X .035 304 SS. This number is subject to expansion
if defects are found. There will be significant destructive
examination performed on called flaws, giving a rare opportunity
to assess real probe performance based on ground truth.
January 2009:
T5 HyTec Probe scheduled for use in Quad Cities main condenser.
After successfully detecting circumferential cracks at
the tubesheet in a mockup provided by Exelon/Master Lee
Energy Services, a T5 HyTec probe has been approved for
use as test of record in the Quad Cities main condenser.
The inspection is scheduled for late April or early May.
November 2008: Preliminary
Results from EPRI Loose Parts Detection Study
Preliminary results from the T5 HyTec probe in a steam
generator loose part detection sutdy are very strong.
Though testing is not complete, EPRI comments that T5 HyTec
"blows away" other techniques in its ability to detect loose
parts resting on top of the tubesheet. Formal results
are scheduled for presentation at a TAG meeting in early
December, with publication of a final report by the end
of the year.
October 2008: Detachable
T5 HyTec probes now available
IEI is proud to announce the availability of DETACHABLE
(and waterproof) probe assemblies. The T5 HyTec probes
pictured here consist of a differential bobbin coil and
a T5 HyTec coil in the same detachable head. Both
the shafts and probe heads are compatible with detachable
components made by another probe vendor after they discontinued
their line of detachable AC probes. This will allow
for continued use of those heads or shafts with IEI mating
parts. Call today for more details and for a quotation.
September 2008: T5 HyTec
S/N ratio is over 250 times better than bobbin at TSP
A laboratory study was recently conducted to compare
T5 HyTec and bobbin singal-to-noise (S/N) ratios.
Circumferential EDM notch responses from each probe were
compared to the un-mixed TSP responses for each probe.
For a 90 degree 100% thru wall circ notch, T5 HyTec exhibited
a 153:1 signal to noise ratio, while a conventional bobbin
coil showed 0.64:1 ratio. T5 HyTec was 239 times better.
In another test using a shorter, 22.5 degree 100% through
wall EDM notch, the T5 HyTec S/N ratio was 28:1, while bobbin
was 0.11:1. T5 HyTec was 254 times better. Once
again, this demonstrates the superiority of T5 HyTec for
inspection of heat exchanger tubing.
August 2008: Independent
Review of T5 HyTec by K&L Engineering
A low frequency T5 HyTec probe was recently provided
to K&L Engineering for unbiased comparison against another
popular AC array probe from another vendor. The probes
were both .560" in diameter and were optimized for testing
enhanced finned copper tubes (fins on both the ID and the
OD). Harry E.
Hendricks, a 40 year veteran of non-destructive testing
(ASNT Level III, PE), performed the evaluation and commented
as follows:
"Corresponding test signals from the two probes indicated
that the T5 HyTec probe was much more capable than the AC
probe for detecting the defects in the eight tubes samples,
i.e. the very stable signal amplitudes were more than twice
those generated by the AC coils." Mr. Hendricks continued,
"the prototype T5 HyTec probe used in this evaluation proved
to be the most sensitive
(hot) probe ever observed by our personnal for detecting
defects in the varying geometry of the transition zones".
July 2008: T5 HyTec
probe detects missed leaker
During a July inspection of an air conditioning unit
at a large computer chip manufacturing company, the attributes
of the T5 HyTec probe were again made evident. Initial
examination of the exchanger with conventional probes did
not reveal any indications typical of a leaking tube.
However, supplemental examination with T5 HyTec allowed
for quick and easy detection of the leaking defect.
The difference is attributed to the ability of T5 HyTec
to completely suppress expansion signals and support signals
at land areas which had masked/distorted the flaw signal
during the initial test with the conventional probe.
According to Gene Auville, president of IEI, "Since the
T5 Hytec eliminated the support signals, the large defect
became obvious. It makes the test so much easier and
with fewer errors". The undistorted T5 HyTec probe
signal measured exactly 40 degrees in phase, allowing for
immediate identification of the indication as the leaking
flaw.
July 2008: "The Best
of Both Worlds": First T5 HyTec hybrid probe constructed
In response to numerous customer requests, IEI recently
embarked on an effort to merge a bobbin probe and a T5 HyTec
probe into one assembly, creating a hybrid design.
Throughout the design process, functionality and durability
were primary concerns. According to our customers,
the benefits of combining the two coil types into one probe
are manifold:
1. The presence of a bobbin coil on the probe allows
new T5 HyTec users to compare potentially unfamiliar T5
HyTec signal responses with familiar bobbin coil responses
for any given defect.
2. The presence of a bobbin coil also allows for
proper historical comparisons with previously collected
bobbin data.
3. The presence of a T5 HyTec coil set within the
probe allows for detection of flaws within expansion transitions,
where bobbin probes offer no reliable detection.
4. The presence of a T5 HyTec coil set within the
probe also allows for full detection of circumferentially
oriented cracks, either in free span or within the aforementioned
expansion transition.
5. Finally, T5 HyTec suppresses TSP signals, eliminating
the need for mix channels.
The new hybrid probe has a titanium wear sleeve covering
both coil sets for enhanced durability. The probe
is available with or without centering devices, with a flat
or tapered nose, and is equipped with a kink-proof poly
shaft. Call today for a quotation!
May 2008:
T5 HyTec inspection at a Nevada
chemical plant
In response to a previously identified concern over the
potential existence of circumferential cracks in a particular
heat exchanger, a special T5 HyTec test was conducted by
The Young Group. The test was conducted on a randomly
selected group of periphery and internal tubes within the
bundle. As designed, T5 HyTec was able to effectively
suppress the tubesheet and expansion signals and provide
reliable detection of circumferential cracks at this location.
According to The Young Group Level III involved with the
test, “T5 HyTec is an effective tool for flaw detection
in the tubesheet expansion, and is a cost-effective alternative
to array or rotating probes”
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