Note: Descriptions are shown in the official language in which they were submitted.
SYSTEM AND METHOD FOR THE IMPROVED ANALYSIS OF
ULTRASONIC WELD DATA
Field of the Invention
The present invention relates generally to software tools for accelerating and
enhancing the data analysis of non-destructive testing using ultrasonic sound
waves in base
metal and welded materials. In particular, the present invention relates to
improving efficient
analysis of ultrasonic weld data pertaining to pipe, plate, and structural
weld seams. In even
greater particularity, the present invention relates to assisted data analysis
of ultrasonic
phased array testing data to increase the speed, reliability, evaluation, and
reporting
efficiency for code compliance of weld inspectors.
Background of the Invention
Bridges, buildings, railroads, pipes, vessels, tanks, and other metal or steel
welded
structures are a vital part of modem infrastructure. These structures are
typically fabricated
from sets of discrete metal sub-components that are welded together to form a
critical
is component and/or a total system. Welded seams and other weld joining
points must be fused
into a welded unit having satisfactory strength to ensure building code
compliance and to
achieve proper structural integrity of the entire system, and/or to ensure
meeting the purpose
of the design for which it was intended. For example, a pressure vessel or
fluid tank must
have water tight exterior as well as provide structural support for the entire
vessel or tank
system. Pipes and vessels similarly must have water or gas sealed, welded
seams to ensure
the integrity of the pipe/vessel and to properly isolate the fluid or gas held
by the pipe from
the environment. In addition, these systems deteriorate over time due to
operational and
environmental factors such as, residual and applied stresses, vibration, rain,
snow, strong
CA 3077548 2020-03-31
winds, temperature variance, earthquakes, oxidation, material fatigue, and
other changes that
occur over the passage of time. Hence, nondestructive testing of welds and
metal structures,
and their components, are utilized after initial fabrication, installation,
and periodically
thereafter, to ensure a structure's integrity. Further, both for new
construction and routine
s
periodic maintenance, careful analysis of the weld joints in each structure is
necessary to
ensure satisfaction of various weld specifications, industry codes, and
construction
regulations. For example, the American Society Mechanical Engineers ("ASME"),
the
American Welding Society ("AWS"), and the American Petroleum Institute
("API"), among
others, each have their own welding codes, procedures, and specifications.
io Modern
inspectors use non-destructive test ("NDT") equipment to inspect
constructed metal (e.g. steel) structures and their weld joints. These
inspection devices use
ultrasonic wave generators to take digital "snap-shots" of welds from which an
inspector
may verify weld integrity and to ensure compliance with welding codes and
specifications.
Ultrasonic technology is used to detect internal and surface breaking flaws in
the weld and
is the
base metal, which are not visible externally, and is based on the principle
that a gap or
defect in the weld changes the propagation of ultrasonic sound through the
metal. One
common method of NDT testing uses conventional, single-probe ultrasonic
testing requiring
an operator's interpretation of a screen similar to an oscilloscope screen
that presents time
and amplitude information. Another method uses an array of ultrasonic phased
array sensors
20 to test
a structure. Such methods can be combined into a single digital piece of
inspection
equipment that uses phased array ("PA") and time-of-flight ("TOFD")
diffraction
methodologies to provide a three dimensional image of a weld displayed on a
color screen.
An inspector then evaluates the potential for a flaw or defect in the weld by
reviewing the
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screen. Such ultrasonic testing ("UT") equipment is typically highly mobile,
and allows for
the recordation of ultrasonic data for the analysis of welded areas in joined
metal pieces. For
example, Olympus NDT, Inc. markets and sells ultrasonic units through its
OmniScanTM and
EpochTM lines of weld flaw detectors. The Olympus ultrasonic inspection
systems include
conventional ultrasonic flaw detectors, which use ultrasonic waveforms to
detect flaws, and
advanced ultrasonic phased array flaw detectors, which create internal cross-
section images
of the areas being inspected. These ultrasonic flaw detectors may also be
configured to do
a phased array ultrasonic testing ("PAUT") inspection that produces encoded
digital data
points on welds which may be further processed at a later time. The data may
also be
reviewed later at a time convenient for an inspector and in an environment
away from the
component or structure's location, which is typically more suitable for
detailed analysis
work. Such ultrasonic data is recorded and saved in large data files which may
be retrieved
for evaluation by an inspector using specialized software applications. While
these data files
are readable by the ultrasonic testing device, software applications also
exist that assist in
the evaluation and visual display of such inspection data on common computing
devices,
such as a PC. An example of such applications is the OmniPCTM analysis
software also
available from Olympus NDT, Inc., along with an additional analysis tool set
called
TomoViewTm. Both of these tools allow for a more precise and reliable review
of the three
dimensional PA data by an inspector.
A phased array data file consists of captured data representative of
continuous
A-scans along a weld which may be processed to create a three dimensional data
set
representative of the top, side, and end views of a weld joint. Within each A-
scan, a series
of recorded data points record an intensity or amplitude value from 0% to 100%
of ultrasonic
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signal reflections. These data points are then saved as OPD, RTD or TV file
formats for
subsequent analysis. Since the recordation of ultrasonic data is correlated to
the exact PA
probe position on the structure being tested, the inspector may use the
analysis software
including various sets of sophisticated analysis tools to review the recorded
data in a number
of geometric views and orientations (e.g. top view, side view, end view) to
improve
inspection review accuracy.
Further information regarding the use of phased array UT equipment,
configuring
such UT equipment, establishing a test scan plan applicable to a particular
inspection or weld
joint design situation, the recording of that data in various file formats,
the physics and
geometries of the ultrasonic sound beams and resulting scanning views in UT,
the use and
applicability of "data" libraries, the storing of testing data files, the
usage of different types
of scan views, the visual analysis of weld flaw indications, and the
generation of inspection
reports based upon UT shall not be discussed herein as such information is
well known
known in the NDT industry and not necessary for a complete understanding of
the disclosed
invention. However, Applicant references the treatise UT Classroom Training
Book, Paul
T. Marks, ISDN No. 978-1-57117-345-4 (e-book), published by The American
Society for
Nondestructive Testing, and two treatises published by Olympus NTD, Inc:
(1)Introduction
to Phased Array Ultrasonic Technology Applications, third printing 2007, ISBN
No. 0-
9735933-4-2; and (2) Advances in Phased Array Ultrasonic Technology
Applications, 2007,
ISBN No. 0-9735933-4-2. The books may be obtained at the ASNT website
www.asnt.org
or the Olympus NDT resources website www.olympus-ims.com. These treatises
explain the
above subjects in detail and the general theory of UT using modern equipment.
Further,
Applicant references
4
Date Recue/Date Received 2020-09-04
U.S. Pat. Nos. US8156813B2, US8577629B2, US9032802B2, US9081490B2. These
patents discuss and disclose background information regarding the electronics
and theory
behind PA ultrasonic testing.
Nevertheless, even with modern PA and time-of-flight UT devices, and even when
inspection analysis is conducted in an environment conducive for careful
study, the data
analysis and reporting process can be a tedious and fatiguing task for
inspectors. For
example, metal pipe and plate structures typically have girth welds and long
seams that must
be inspected. PA ultrasonic and time-of-flight, diffraction inspection for
those welds seams
can produce extremely large data files requiring many hours of data review and
analysis of
all data points along the weld seams by an inspector. Usually most of the data
points are
nominal, satisfactory welds, creating a monotonous review period and
potentially reducing
weld flaw recognition by an inspector due to fatigue. Hence, what would
enhance the
inspection process would be a system for focusing an inspector's attention on
actual weld
defect indications, by excluding data points that present satisfactory and
acceptable weld
characteristics. Such a system would improve an inspector's efficiency and
accuracy in
conducting new or reviewing prior weld inspections, thereby saving time and
money.
Summary of the Invention
In summary, the invention reads data from PAUT or TOFD data files that capture
ultrasonic testing results from a series of metal welds, or a set of
continuous welded metal
seams, and creates a table of target indications requiring an inspector's
review and
evaluation. The invention reads one or more testing data files and collects
weld indications
from the data files, applies a series of filters to each recorded indication,
and ranks the
indications in a meritorious order, including the application of color coding
to these
5
Date Recue/Date Received 2020-09-04
indications to assist the inspector in analysis of the testing data file. The
invention acts as a
weld analysis concentrator by focusing the attention of an inspector on weld
targets that
merit their attention, thereby increasing the efficiency of the inspector. The
process typically
excludes 95% to 98% of the weld data, while retaining significant flaw
indications necessary
for an inspector's review and in conformity with inspection regulations from
various
organizations establishing weld codes and specifications.
Other features and objects and advantages of the present invention will become
apparent from a reading of the following description as well as a study of the
appended
drawings.
Brief Description of the Drawings
The patent or application file contains at least one drawing executed in
color. Copies
of this patent or patent application publication with color drawing(s) will be
provided by the
Office upon request and payment of the necessary fee.
A system incorporating the features of the invention is depicted in the
attached
drawings which form a portion of the disclosure and wherein:
Figure 1 a side view of a typical ultrasonic testing system for a pipe weld
seam using
a phased array or time-of-flight inspection system;
Figure 2 is a perspective view of a typical ultrasonic testing scenario for a
pipe weld
seam using a phased array system or time-of-flight inspection system;
Fig. 3 is an S-scan view showing a two dimensional scan matrix overlay of
refracted
sound wave angles in a typical ultrasonic testing scenario for a pipe weld
seam showing a
potential weld flaw;
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Figure 4 depicts a plan view with a matrix overlay showing the locations and
recordations of ultrasonic data on the information displayed in the graph of
Fig. 3;
Figure 4A is a diagram of a data cuboid;
Figure 4B depicts an end view of a weld with a matrix overlay showing the
locations
and recordations of ultrasonic data from the information displayed in the
graph of Fig. 3;
Figure 5 is a process flow diagram of the overall invention process;
Figure 6 is another process flow diagram of the invention process;
Figure 7 is a process flow diagram showing the data filtration process
utilized in the
invention; and,
io Figure 8 is a representative depiction of a spreadsheet chart
produced by the
invention after processing of weld indications showing color coding.
Description of the Preferred Embodiments
Referring to the drawings for a better understanding of the function and
structure of
the invention, Fig. 1 shows a side view 10 of a typical ultrasonic testing
scenario for a steel
1, pipe weld seam using a phased array ultrasonic tester. The pipe 11
includes two sections
12a and 12b joined together via weld seam 23. Each piece of the pipe separates
the
environment in which it is positioned into an interior 13 and an exterior 16,
with each pipe
section having an interior surface 17 and exterior surface 18 contacting the
interior and
exterior spaces. As may be noted, this arrangement would be similar for other
weld joint
20 designs such as vessels, tanks, and structural members. Each section
12a and 12b extends
away from weld seam 23 curving downwards on each side 21, 22 to enclose
interior 13. The
weld seam 23 is typically "V" shaped having an upper width 24 larger than
bottom width
27, but may have other shapes as is known. The top of weld 23 typically has a
portion of
7
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excess weld material 26 that extends slightly above the exterior of the pipe
18 for
reinforcement.
Positioned adjacent to the pipe 11 is a phased array UT probe 31 including a
transducer probe 32 having an angled probe wedge 34, an ultrasonic array
transmitter and
receiver element 36, and a connection cord 33 connected to a testing device 37
(not shown).
In addition to an electrical signal wire, such as a coaxial cable, the cord 33
may also include
a tube for the transmission of water or other fluid (known as "couplant") in
which to couple
the phased array probe and wedge to the base material and in order to
efficiently transmit
the ultrasonic sound waves into the base metal and weld metal.
The probe 36 emits ultrasonic waves from elements held in probe 31 that are
controlled by testing device 37 at timed intervals to create various types of
wave fronts or
sound beams that are propagated through the metal of the base metal 11 and the
weld material
23. This results in a series of longitudinal wave beams or shear wave beams
39. The sonic
beams 39 vary in angle generally from about 45 degrees to 70 degrees,
refracting through
the weld 23 and surrounding base metal 12a,12b, and produce ultrasonic
reflections received
by probe 31 that are sent back to testing device 37. The combination of the
wave segments
39, software that controls the timing, frequency, emission position, and other
qualities of
those sound wave beams, and the position of the probe 31 adjacent to the weld
seam 23, is
designed to reveal weld flaws 41 that may be present in or around the weld
seam. The wave
beams 39 will typically generate reflections off the interior surface 17 and
exterior surface
18 (not shown).
Referring to Fig. 2 probe head 31 is positioned adjacent to weld seam 23 and
scanned
along the length of the weld seam direction 29 joining two sections 12a, 12b
of pipe 11.
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Since weld seam 23 has approximately a V-shape as shown in Fig. 1, the
extension of seam
23 along 29 creates a wedge shaped weld seam. Testing probe 31 positioned
adjacent to
weld seam 23 is moved in direction 37 along the length of seam 29 while
transmitting
ultrasonic sound waves to the interior of the seam weld and surrounding weld
metal. At all
times, probe 31 tracks its position along seam 23 and its index position from
the centerline
of the weld seam as it scans along the weld seam. The weld seam may be scanned
manually,
semi-automatically, or automatically through encoded or motorized means, as is
understood
in the art. While the probe 31 is shown to be positioned on one side of weld
seam 23, the
probe may be positioned on the other side with equally effective results. In
addition, multiple
io probes may be utilized at the same time.
Referring now to Fig. 3 an ultrasonic data sampling system 45 of wave segments
and
samples is shown in a sectorial diagram similar to Fig. 1. The system 45 shows
a typical
sampling arrangement used in recording data from phased array or time-of-
flight diffraction
UT scanning of a weld seam. The diagram 45 approximates an example of a
sectorial or "S-
scan" view of a weld, non-destructively tested with ultrasonic waves as may be
understood.
Weld 23 is positioned in the middle of the system 45 having sound beam
segments 39 with
probe head 31 positioned at the origin of the sampling system 45. Due to the
proximity to
the probe, area 44 just under the probe 31 is either not included during
scanning or excluded
later during processing. The arrangement of the sound beam segments and
sampling data
points produces a two dimensional scan matrix 50 of each scan slice of data
taken along
weld seam 23. Each matrix 50 is not rectangular, but has a radial shape as
shown, with each
data point having a coordinate location of (a) scan offset, (b) beam, and (c)
sample index, as
will be further discussed. Hence, each data point sample 53 is composed of its
three
9
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dimensional coordinate and an amplitude value representing the strength of the
reflection
from beams 39 at that point in space. That information can also be organized
in a three
dimension rectangular array in the form of a "cuboid" or a "voxel" as will be
discussed in
Fig. 4A.
As ultrasonic waves 39 are transmitted into the weld area 23 from probe 31 any
potential weld defects 41 will produce ultrasonic reflections back to probe 31
which are
received and recorded as a group of data points having elevated amplitude
values. Sound
beam segment 47 is approximately 45 degrees from normal, and beam segment 48
is
approximately 70 degrees from normal incidence. Other angles of sound waves 39
span the
to angular distance between segments 47 and 48 such that the entire
weld area for any current
segment is covered by these scanning segments, including wave segments 49 that
impinge
upon potential flaw 41. Since the entire area has angles of sound waves
transmitted through
the base material and weld seam, any potential flaws 41 in the weld seam 23
will be contacted
by one or more of the sound waves. Within the system 45, potential flaw 41 is
within a
bounded area 46 of data points that surrounds the potential flaw. As may be
understood,
the cells shown in Fig. 3 are not to scale and provided for illustrative
purposes only to show
the workings of the herein disclosed invention. The resolution of a typically
overlay would
normally be many times finer than that shown by the matrix 50.
System 45 also includes three zones of interest in any scan. Zone 1 56 is
positioned
along the interior surface 17 of the weld 23 and includes all data cells along
that surface.
Zone 3 58 is positioned along the exterior surface 18 of weld 11 and includes
all data sample
cells along that surface. Reflections from zones 1 and 3 may be filtered for
more in-depth
data analysis, depending upon the content of that data and the type of filter
being applied.
CA 3077548 2020-03-31
Zone 2 57 is positioned between zones 1 and 3 and includes all data cells not
in zones 1 and
3 and are part of an analyzed set of data points in later processing.
Fig. 4 shows a rectangular coordinate system overlaid on a top-down or "C-
scan"
view of the seam shown in Fig. 2. As indicated above, the coordinate system 50
is not
rectangular, however because each data point has a point in three dimensional
space in the
scanned workpiece a corresponding point in space may be recorded in a
coordinate matrix
overlay 60 of data cells. In particular, the combination of rows 61 and
columns 62 produces
a rectangular matrix of cells that will contain each data point sample 53 in
the coordinate
system 60 as the probe 31 is moved along weld seam 23 (rows R3 and R4) in
direction 29.
to Potential weld flaw 41 would be recorded in at least 6 cells, such as 63
in this depiction (i.e.
R4, C4-R4,C6; R5,C4-R5,C6). A similar end-view or "B-scan" view looking into
the weld
having from one end with a coordinate overlay might similarly be produced and
is shown in
Fig. 4B. In particular, the combination of rows 161 and columns 162 produces a
coordinate
matrix overlay 160 of data cells viewed from the end of the weld seam 23 in
either direction
along 29 at a particular scan offset. Potential weld flaw 163 would be
recorded in at least 6
cells 166 shown surrounding potential flaw 163. Each cell has a two
dimensional
measurement as depicted in Fig. 4A.
As shown in Fig. 4A, an example of each data cell referred to hereinafter as a
"cuboid" (or "voxel") or "data cuboid" 65 has length 66 of about .04 inches, a
width 67 of
about .02 inches, and height 68 of about .02 inches. As will be understood,
these values may
change based upon a variety of factors associated with each weld scan. While
the coordinate
systems shown in Figs. 3 and 4 are two dimensional, in reality each scan
snapshot taken
along seam 23 has a sample width of .02 inches due to the way in which
ultrasonic waves
11
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are transmitted into the material. Hence, each cuboid 65 is in reality three
dimensional. UT
probe 31 takes sectional scan snap-shots along weld seam 23 along travel path
37 (see Fig.
2) with each section scan recorded as a matrix of cuboid data values in a
file, adding a new
matrix section of data with each new sectional snap-shot.
Each recorded data cuboid has a set of values associated with it, comprising
the prior
noted three dimensional coordinate set of system 45 (see Fig. 3) and an
amplitude value.
The coordinate portion includes the values of depth from the top surface of
the pipe also
referred to as (1) the "ultrasonic axis" distance; (2) an index axis (or
"index offset") which
is the distance from the center line of the weld 23; and (3) a "scan axis"
value (or "scan
io offset") which is the distance along the weld as recorded by the
probe as it travels along path
37. The amplitude value is a reflection value (i.e. a sound intensity value)
recorded by the
probe 31 normalized to a relative value of between 0% and 100%.
In actuality, each scan section includes raw data position values of (1) scan
positon
of the probe head as it tracks along the weld seam, (2) an angle value
representing the angle
of a wave segment as it is emitted from the probe emitter, typically between
45 and 70
degrees, and (3) a sample index value which is the distance from the probe
emitter. Using a
known set of geometric calculations for polar coordinates, any scan data value
position in
any data cuboid may be determined when data values are retrieved from the scan
data file
("SDF") as will be discussed.
20 Referring now to Fig. 5 a system is presented 70 that reduces the
number of weld
scan indications that an inspector must review in order to produce a report
meeting
applicable welding examination codes and requirements, such as those published
by ASME,
AWS, or other organizations. The system 70 is a standard software application
that may run
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on a standard WindowsTM operating system, such as for example Windows 7 sold
by
Microsoft Corporation, running on a standard PC configuration. The system may
also be
incorporated as a module directly into existing testing and/or scan analysis
software.
Initially, an inspector assesses a weld situation and then configures their UT
equipment for
a scan, including the positioning of the UT probe 72 adjacent to a target
weld. The weld is
scanned by the inspector 73 and a data file recording the weld scan data saved
74. The data
may be saved locally on the UT device, transferred to a connected drive
storage 76, or
uploaded to a network drive via Wi-Fi or other data connection, depending upon
the size of
the data file. The scan file is then processed 77 by extracting all data
cuboids that include
potential weld flaw indications, essentially extracting all cuboids that have
amplitudes
greater than 0, and then creates a file recording those indications and saves
it in a local, fast
access storage location 78. Further processing occurs on the indications file
by applying a
series of filters 81 that ranks and categorizes the indications into a usable
form. In particular,
a ranked list of indications is created in a table based on a ranking value
for each indication
is which consists of multiple data cuboids. That priority listing of
indications is then produced
82 and displayed 83 for the inspector's analysis at a place and time of their
choosing. The
process shown in 70, typically removes over 95 percent of the non-relevant
data stored in a
scan data file, and presents a focused list of only a fraction of the overall
indications held by
a scan data file, without degrading an inspector's ability to properly review
the scan data in
accordance with applicable code requirements.
Fig. 6 shows the benefit of this system 70 in a typical operation 90 by an
inspector.
A phased array UT is arranged, configured, and then used to scan a weld under
review 92.
A scan data file is created and that file is saved locally, or at a remote
storage location such
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as a cloud based drive 95 via the internet 94. The data file is then accessed
at a later time
and processed 97 to extract its weld indications and filtered to remove
indications that do
not merit review. That processing 97 may occur at the initiation of an
inspector, or it may
be automated upon the arrival of the data file at storage location 95. The
inspector can then
review the published report of target indications 98 and using a compatible
scan data
visualization application or device 100 review each indication listed in the
published
indications report that merits careful study. The inspector may then produce
their own
inspection report 99, saving it in a local storage location, and may take
remedial action 102
to correct any noted weld defects.
Turning now to Figs. 7 and 8, it may be seen the detailed operation of the
system 70
along with an example report table produced by the system in a typical pipe
weld seam
situation. A typical industry UT device is an Olympus OmniScanTM MX2 phased
array flaw
detector. That device produces a scan data file in the form of an OmniScan
Phased Array
Data File or "OPD" file. That OPD file may be saved in a storage location for
later review
and accessed by various visualization applications to graphically review any
portion of the
scan along a pipe weld seam. Each OPD file includes configuration and setup
information
such as weld type, weld bevel angle, thickness of the pipe material, the
ultrasonic velocity
utilized, probe scan and index offset, and probe skew, and also includes
information on how
many scan jobs are included in the file. Additionally the overall scan length
is recorded and
a sound path minimum value recorded. That information is utilized by the
process 105 as
will be discussed.
As shown in the process 105 of Fig. 7 an OPD file is read 107 from a storage
location
108. The accessing of data in the OPD file may be accomplished with the help
of an
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intervening software module known as a data access library or "DAL." The DAL
is typically
written or authorized to be written by the author of the OPD file
specification, which in this
example is Olympus NDT. Whether read directly from the OPD file, or indirectly
through
the use of a DAL, the data is retrieved in the form of a scan position, a beam
number (i.e.
beam angle), a sample index (i.e. sample number along the beam), and a data
point value
(i.e. magnitude) at the corresponding sample. System 105 accesses the OPD file
by making
a data retrieval request pursuant to an instruction format specified by DAL
111 which allows
the extraction of all data cuboids in the scan data file. Any data scan
cuboids accessed but
having no amplitude are not saved, so only cuboids that are potentially part
of a weld
indication are retained. A local database file is created to hold those
indications in a three
dimensional matrix referenced by position and amplitude values, which is then
stored 112.
The system further examines the amplitude of each data cuboid in the database
and
excludes any cuboids that have a value less than or equal to 16%. Sixteen
percent is a value
derived from weld code specifications below which scan reflection data does
not typically
need to be reviewed by an inspector. Each data cuboid remaining in the
database is then
analyzed to determine if any adjacently positioned cuboids to the one being
analyzed also
have been retained (i.e. their intensity values were also above 16%, see e.g.
Fig. 3, 46, Fig.
4, 63). A first cuboid is considered adjacent to a second cuboid if they
differ by only one
position in scan, beam, and/or sample coordinate(s). Such remaining contiguous
cuboids
are then grouped together and referred to as an individual "indication" to
signify a potential
flaw indication that requires an inspector's review. Each cuboid is similarly
analyzed until
each cuboid is assigned into a unique weld indication 109. Several properties
of each weld
indication are also calculated and utilized in further processing of each
indication. Namely,
CA 3077548 2020-03-31
information such as depth, index position, and scan position range limits are
recorded; the
maximum intensity position within the indication is calculated to give a sense
of a "center
of gravity" for each indication; and the maximum amplitude of all cuboids in
the indication
is recorded 112.
Each indication is also given a unique ID based on a hashing of cuboid data
contained
in the indication. As may be understood, any identical A-scan data will always
produce the
same unique hash ID for each indication.
The process 105 also assigns a significance score to each indication to
produce a
priority ranking order of indications needing attention. That significance
score is a value
assigned to each indication between 0 and 1, with 1 being the highest value,
and represents
a best estimation on the part of the process 105 to draw the attention of the
inspector to an
indication that is more likely to be a flaw. A series of filters 115 are
applied to each
indication that affects the significance score and which is used to form a
ranking 124 of each
unique ID. Each flaw indication is ranked in a table based on this
significance value as will
be discussed in Fig. 8. Each indication starts with an initial value of 1, and
resulting filter
values are multiplied together and then multiplied by 1. Hence, and as will be
seen, some
filters are essentially fully exclusionary because they only return either a 1
or a zero. Other
filters return a value between 0 and 1 that may reduce the significance score
of the indication
or leave it at 1.
Filter 116 is a minimum size filter 116 which is applied to each indication.
If an
indication is below a minimum threshold size, that indication is assigned a
significance score
of zero. Specifically, if an indication includes a number of contiguous
cuboids less than a
threshold value, a zero is assigned to that unique indication ID.
Alternatively, a 1 is returned
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if the filter 116 does not apply. Currently, the ASME code specifies threshold
values of 0.08
inches length (scan dimension), 0.06 inches width (index dimension), and 0.06
inches height
which might change with each particular scan situation.
Also, any flaw indications that are too close to the probe emitter 117 (see
Fig. 3, 44)
returns a value of zero which would result in a significance value of zero.
Indications are
discarded (i.e. assigned a zero score) due to the distortions that are
experienced near the
probe head in the pipe material. So, any indications that are within 25% of
the scanned
workpiece thickness from the probe head are assigned a zero significance score
117.
Alternatively, a 1 is returned if the filter 117 does not apply.
Reflection of sound waves is timed in each UT device and any indications that
are
more distant than a predetermined percentage of the pipe steel thickness
distance (e.g.
indications in Zones 1 and 3 of Fig. 3), and also as set by welding code
specifications, are
assigned a zero significance score 118. Alternatively, a 1 is returned if the
filter 118 does
not apply.
is Also, any reflections that are more distant than a set lateral
distance from the weld
23 are assigned a value 119 between zero and 1 representing a reduction in
significance in
that indication the farther away an indication is it positioned away from the
weld centerline.
The significance factoring for filter 119 is shown in the processing pseudo
code of Table 1
below.
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Let MAX = maximum distance from weld before an indication may be
disregarded by the code (currently this value is 2" if the part thickness is
8"
or more, otherwise the minimum of 1" or the part thickness).
If an indication is farther away than MAX from the weld it is considered
not in the "heat affected zone" or HAZ.
Let DIST = the lateral distance (i.e., in the index offset dimension) of the
indication from the weld surface.
Let DI = DIST / MAX
If D1 <= 0.25, return score= 1.0
If D1 >= 1.0 return score = 0Ø
Otherwise return score = (DI - 0.25)! 0.75 (i.e. linearly interpolate).
Table 1
As part of the UT scanning process, it is typical that some inherent noise
echoes or
"hot spots," also known as "root or weld cap geometry signals," will be
created for each
sectorial scan as the probe traverses along the weld seam. Essentially, these
false returns are
artifacts that are produced by the geometries of the top and bottom weld caps.
The nature
of these hot spots is that they are periodically repeated along the seam at
regular intervals
and typically have common characteristics between one another, namely they
appear at
substantially the same index offset and depth locations. Since these hot spots
represent false
flaw indications, filter 121 assigns a reduction in significance score to all
such indications
la which are likely to be false returns due to these ultrasonic
geometries. The significance
factoring sub-process for filter 121 is shown in the processing pseudo code of
Table 2 below.
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Let S = {s1, bl, ml}, {s2, b2, m2}, . . . , be the set of 3D
coordinates (in Scan, Beam, and saMple) of all voxels/data points
within the indication. This will represent a contiguous region/blob
of data points in 3 dimensions. Each data point will have an
associated amplitude measured from 0 to 100.
Let MAX = maximum amplitude of all of the amplitudes of all the
coordinates in S.
Let P = {bl, m1}, {b2, m2}, . . . be the set of 2D coordinates in
beam and sample dimensions that results when you take all of the
3D coordinates in S and simply discard their scan coordinate; if
there are any duplicates, discard the duplicates. (i.e. P is the
projection of S along the scan dimension).
For each coordinate {b', m'} in P. let TYPICAL(b', m') be the
average amplitude over all data points {s', b', m'}, where s' ranges
over all possible values except for those values where {s', b', m'} is
a member of S.
For each {b', m'} in P, let RATIO(b', m') = MAX / TYPICAL(b',
m').
Let AVGRATIO = average of RATIO(b', m') over all points {b',
m'} in set P.
If AVGRATIO >= 2.0 then return score 1.0
If AVGRATIO <= 0.25 then return score 0.0
Otherwise, return score = (AVGRATIO - 0.25) / 1.75 (i.e. linearly
interpolate).
Table 2
As may be understood, the filters incorporated in 115 may be altered in their
variables
and operation to lesson or increase their individual effects on an
indication's significance
score. In addition, more filters might be incorporated in the future as weld
specifications
and codes are updated, or resulting from better understanding of flaw
indications present in
an ultrasonic weld scan.
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After filters 115 are applied to the indications held in database 112, the
indications
are ranked 124 based upon their resultant significance values. Color
designations are then
applied 126 to each ranked indication to assist an inspector in correlating
the same instance
of an indication over multiple scanning data files. A designation ranking
table is then
published 127 for the inspector's use in evaluating an OPD data file.
Fig. 8 shows an abridged ranking report of flaw indications that can be relied
upon
by an inspector to focus their attention on important indications. The chart
130 is used for
example purposes only and as will be understood any real weld scan data file
would likely
include hundreds of indications, but chart 130 is abridged to show only 45
entries for
illustration purposes but still show the usefulness of the report. The chart
130 is a spread
sheet and displays 45 rows each representing a flaw indication ranked in order
of
significance from 2 to 45 in rows, row 2 being the most important flaw
indication and row
46 the least significant indication. Each indication is assigned a unique ID
created via a
hashing function as shown in column A 132. Also, a series of columns with
headings 140
provides characteristic information on each indication. Individual entries in
column A 132
may be hyperlinked to views in a cooperative data scan visualization program
allowing for
direct selection of any indication in the chart for instant viewing in the
scan visualization
application. Column B 133 displays the scan file from which the indication was
produced,
and as can be seen at least 4 different scan files were processed by system
105 to produce
the table 130. The chart also indicates the probe group from which the samples
were taken
134. Rankings shown in Column D 135 list all indications retrieved from the
scan data file
in descending order from the highest value of 1.00 to the lowest value of
0.00. Alternatively,
the chart may be reordered to arrange indications in a direction running along
the weld
CA 3077548 2020-03-31
length. Column F 138 shows the maximum amplitude of any cuboid present in any
indication, typically close to the center of gravity of any indication. The
refracted angle of
the indication is shown in Column J 141. The scan position, index position,
and surface
distance are shown in columns K 142-M 144. The sound path is shown in column N
146,
and the indication depth is shown in column 0 147.
Color coding is also utilized to assist an inspector in recognizing certain
attributes of
indications. First, rankings in column D 135 are assigned a graduated scale
from red to blue
using the color spectrum to show a high ranking to a lower ranking. For
example, the top
entries in rows 2-11 have a bright red color indicating importance, while the
last 10 entries
10 in rows 36 to 46 are a cooler color or deep blue indicating low
importance. Location match
column E 137 displays a color based on location for each indication by
assigning color values
from a color palette to the center of gravity value of each indication and
using depth of the
center of gravity indication as a red value, using the scan position of the
center of gravity
indication as a green value, and using the index positon of the center of
gravity indication as
a blue value. Hence, even if multiple scan files are produced and analyzed in
the process
105, a color location match will assist the inspector in recognizing repeated
indications for
the same position along the weld seam. So, for example, entries on rows 13 and
18, which
come from different scan data files, are likely from the same three
dimensional location
along the seam because they have similar colors listed in column E 137.
Finally, amplitudes
are color coded to indicate their relative position between 0% and 100%
similarly to the
assignments of ranking. However, because high amplitudes do not necessarily
lead to high
ranking, colors do not show as a graduated scale in the present example, as in
column D 135
for instance, because the indications ranking of 130 is sorted on ranking and
not on amplitude
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value. Nevertheless, the color does provide a visual indication of amplitude
that may be
useful when correlating a particular indication in a scan visualization
application to the chart
130.
As may be seen, entries 2-18 149 show rankings from 1.00 to 0.71. These
rankings
would likely be the most important indications for an inspector to review on
the scan
visualization application to determine whether remedial action is necessary.
Lower entries
152 and 151 may not need to be reviewed or reviewed with less scrutiny than
usual. Entries
40-46 151 probably need no or only cursory attention from the inspector. Also,
as might be
understood, the listed indications might be re-sorted in additional tabs under
chart 130 to
further assist in focusing the inspector on indications of interest. For
example, a subsequent
tab might list only the top 30 indications.
Overall an inspector having to review the four listed scan files in scan
visualization
software would take a great deal of time to review each and every indication,
but using the
chart shown in Fig. 8 an inspector can quickly focus their attention on
indications that merit
detailed scrutiny.
While I have shown my invention in one form, it will be obvious to those
skilled in
the art that it is not so limited but is susceptible of various changes and
modifications without
departing from the spirit thereof.
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