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920-218A-EN
The Standard in Phased Array, Redefined Bright,LargeSizeScreen Fast,IntuitiveTouchScreen
Interface AdvancedWeldOverlay High-CapacityDataStorage FastFileTransfer
PHASED ARRAY FLAW DETECTOR
OmniScan MX2
2 www.olympus-ims.comwww.olympus-ims.com
The result of over 10 years of proven leadership in modular NDT test platforms, the OmniScan MX has been the most successful portable and modular phased array test instrument produced by Olympus to date, with thousands of units in use throughout the world.
Building on a Solid BasisThis second generation OmniScan MX2 increases testing efficiencies, ensuring superior manual and advanced AUT application performance with faster setups, test cycles, and reporting, in addition to uni-versal compatibility with all phased array modules: past, present and future. Designed for NDT phased array leaders, this high-end, scalable platform deliv-ers true next-generation NDT testing.
The OmniScan MX2 offers a high acquisition rate and new powerful software featuresin a portable, modular instrumentto efficiently perform manual and automated inspections.
Faster Is Better!Powerstart your day the right way with the OmniScan MX2. The OmniScan MX2 simplifies and speeds up the setup process with its new Weld Overlay software feature, so you can start testing immediately. Featuring the industry-standard Phased Array User Interface with faster than ever perfor-mance, a bigger and brighter 10.4in. screen, new and unique intuitive touch screen capabilities, and faster data transfer, enabling you to get to your next inspection quicker.
More Rugged than EverThe OmniScan MX2 is now designed for IP66. It is built to endure the drops, spills, and abuse that typically occur in your most demanding inspection environments.
More than an Instrument A Solution ProviderThe OmniScan MX2 is an important part of your in-spection solution that can be combined with other critical components to form a complete inspec-tion system. Olympus offers a complete product range which includes phased array probes, scan-ners, analysis software, and accessories, which are integrated and packaged into rapidly deployable, application-specific solution packages for quick returns on your investment. In addition, Olympus offers a high-quality calibration and repair service worldwide that is backed by a team of phased array application experts to ensure you get the support you need.
The Standard in Phased Array, Redefined
3Life-Size OmniScan MX2
4 www.olympus-ims.comwww.olympus-ims.com
Bright 10.4 in. Screen
Touch Screen InterfaceThe revolutionary touch screen interface offers simple and quick navigation, enhanced text input functions, and easier, faster cursor manipulation and gate setup.
Full-Screen ModeThe unique full-screen mode offers operators increased viewing comfort, in addition to better readability at a distance. This feature can be used in both acquisition and analysis mode.
Weld Overlay WizardThe Weld Overlay Wizard facilitates the creation of industry-standard weld over-lays for analysis assistance and volumetric flaw placement.
OmniScan MX2OmniScan MX
OmniScan MX
OmniScan MX2 50% larger screen
OmniScan MX
OmniScan MX2 100% brighter screen
55
Modular Instrument Backward Compatible. Forward Compatible. An Evolving Platform for your Growing Needs.Designed to secure both your current and future phased array invest-ments, the OmniScan MX2 can house any Olympus phased array mod-ulewhether the reliable, field-proven models currently available, or the next-generation modules of the future. Its open architecture also supports future software updates and phased array module upgrades with configu-rations from 16:64M to 32:128 to ensure that your platform evolves with your testing needs, and that you get the most from your investment.
Module Compatibility OmniScan MX2 OmniScan MXOMNI-M-PA1664M OMNI-M-PA1664 OMNI-M-PA16128 OMNI-M-PA16128PR OMNI-M-PA32128 OMNI-M-PA32128PR OMNI-M-PA3232 OMNI-M-UT OMNI-M-ECT/ECA Software CompatibilityMXU-3.X1 MXU-2.X setup and data file TomoView 2.9R71, 2
1. Older versions are not compatible with the OmniScan MX2.2. Data file compatibility, no data acquisition.
16:64 PA M 16:64 PA16:128 PA
32:32 PA32:128 PA
6 www.olympus-ims.com
Setting Up for SuccessTouch ScreenThe bright 10.4 in. screen with its revolutionary touch screen interface offers simple and quick navigation, enhanced text input functions, and easier, faster cursor navigation and gate setup.
Zooming and Panning
Menu Selection and Parameter Settings
Text and Value Input
Gate Selection and Movement
The touch screens zooming functions can be used to zoom in on a specific area. In Zoom mode, tap, hold, and drag to create a selection rectangle, and then release to zoom in on the area.
In Zoom mode, swipe to pan the window contents.
Tap once on the screen to quickly navigate through menus, sub-menus and param-eters.
Double-tap on a parameter to bring up the keyboard or keypad on which values can be entered.
In Cursor mode, tap once on a cursor to select it. Double-tap on a posi-tion to move the cursor to the desired location.
In Gate mode, tap and hold on a gate to move the gate to a new position.
7SetupGroup Wizard for All Essential Parameters: Material selection, with a database for shear and longitudinal
velocities, and configuration of components for flat or curved surfaces.
Group copy Wizard for fast creation of symmetrical two-probe inspections.
Wedge selection from a database of Olympus wedges. Auto probe detection. Scanner configuration with offsets, skews, and probe positions. Wizard guidance for phased array, conventional UT, and
TOFD channels. Detailed interactive illustrated help menu for every step in the
Wizard. Weld Overlay and RayTracing.
Setup SpeedOmniScan MX
OmniScan MX2 50% faster
S-Scan and A-Scan Display Refresh RateOmniScan MX
OmniScan MX2 300% better
CalibrationCode-Compliant CalibrationThe Calibration Wizards ensure that every focal law in every group is the direct equivalent of a single-channel conventional flaw detector.
Calibration Wizards Calibration Wizards guide the user step-by-step through
Velocity, Wedge Delay, Sensitivity, TCG, DAC, and DGS calibrations.
Enable experimental or theoretical sensitivity and TCG curves based on 2, 3, or all beams for a real or interpolated calibration.
Simple, easy-to-use interface that enables all focal laws to be visualized simultaneously for a particular calibration task.
Interactive help menu with detailed graphics and definitions, which is available in each step of the Wizard.
Scan plan adjustment using the focal law configuration wizard.
Sensitivity calibration for a defined section in a sectorial scan.
Sensitivity calibration for all beams in a sectorial scan.
UT parameter adjustment using the touch screen software keypad.
8 www.olympus-ims.com
Acquisition A scan menu for quick and easy configuration of inspection
parameters for manual, one-line, raster, and helicoidal scans. Encoder configuration for clock, and one- or two-axis
inspections. C-scan configuration for amplitude and position C-scans, and
display setup. Data storage options for full A-scans, S-scans, and/or C-scans. Preconfigured display layouts for easy inspection preparation. PRF auto adjustments for optimized, maximum speed, or
manually-controlled settings. Data storage options for flash card or USB media devices. Real-time data acquisition displays, with the ability to rewrite
data in both scan directions when using an encoder. Easy-to-use interface with mechanized or semi-automated
scanner systems, and simple wheel encoders.
Pulse Repetition Frequency (PRF)OmniScan MX
OmniScan MX2 40% better
Saving Inspection Data File to USB (speed)OmniScan MX
OmniScan MX2 Up to 400% better
Maximum File Size (Mb)OmniScan MX 160 Mb
OmniScan MX2 300 Mb
Analysis An extensive display menu for preconfigured multigroup and
multiprobe inspection layouts. Data, reference, and measurement cursors for defect sizing
and reporting. Extensive Readings database for trigonometry, flaw statistics on
axes, volumetric position information, code-based acceptance criteria, corrosion mapping statistics, etc.
All Readings are available online, or off-line when full A-scans are saved in data files.
Linked displays for interactive analysis on A-scans, B-scans, S-scans, and C-scans for multigroup and multiprobe inspections.
Optimized preconfigured layouts for quick and simple length, depth, and height sizing of flaws for code-based or non-code-based inspections.
Interactive off-line gate repositioning.
Flawless Data ManagementAn SD Card is used to store data for easy transfer to a computer. The SD card can also be inserted and removed without having to reboot the unit. In addition, data can be transferred to exter-nal media using the USB 2.0 port. The OmniScan MX2 provides data transfer speeds up to 400% faster than the OmniScan MX (depending on the device used).
Top: Data acquisition displaying TOFD.
Right: Data acquisition displaying two phased
array channels and TOFD.
Weld inspection display showing the position of indications in the RayTracing display.
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Page 1 sur 9
OmniScan ReportReport Date Report Version File Name Inspection Date Inspection Version Save Mode
2011 / 01 / 11 MXU - 3.0B4T12 PV200steph2.opd 2010 / 12 / 20 MXU - 3.0B4T10 Inspection Data
OmniScan Type OmniScan Serial # Module Type Module Serial # Calibration Due Data File Name
N/AOMNI-
EQUX251C AMP127 OMNI-2037 2011/8/12 File####
Group 1
SetupA:70.00 Sk:090 L:001Beam Delay Start (Half Path) Range (Half Path) Max. PRF Type
Averaging Factor
22.1 us11.70 mm 61.40 mm 35
PA1
Scale Type Scale Factor Video Filter Pretrig. Rectification Filter
Compression 12Off
0.00 sFW
None 0.50 - 19.00 MHz
VoltageGain
ModeWave Type Sound Velocity Pulse Width
40 (Low) 40.35 dBPE (Pulse-Echo) Shear
3240.0 m/s 100.00 ns
Scan Offset Index Offset SkewC-scan time resolution
-81.00 mm -21.50 mm 90.010.0 ns
GateStart
WidthThreshold Synchro.
I0.00 mm
11.00 mm 20.00 %Pulse
A7.00 mm
15.00 mm 50.00 %Pulse
B72.71 mm 11.00 mm 30.00 %
Pulse
TCG Point Number Position (Half Path) Gain
10.00 mm
0.0 dB
211.98 mm 1.2 dB
317.88 mm 5.0 dB
CalculatorElement Qty. Used First Element Last Element Resolution Wave Type Material Velocity
161
321.0
Shear3240.0 m/s
Start Angle Stop Angle Angle Resolution Focal Depth Law Configuration
70.00N/A
N/A12.00 mm Linear
Page 9 sur 9
Indication # ScanIndex Group Channel A%
DA^ViA^
VsA^ A%DA^
U(m-r) S(m-r)
1109.00 mm -11.63 mm 2
55.00 67.7 % 5.60 mm -1.77 mm 109.00 mm 67.7 % 5.60 mm 6.84 mm 33.00 mm
Comments
-
The RayTracing is only a graphical representation of the readings approved by the operator.
Technician Name
____________________________________________________________________________________________________________________
Technician Signature ____________________________________________________________________________________________________________________
Contractor____________________________________________________________________________________________________________________
Date
____________________________________________________________________________________________________________________
Indication table built from composite inspection data.
TomoView offers advanced post-processing of OmniScan data. Illustrated here: weld overlay, multiple sector scans, multibeam C-scans, and merging of A-scans with Top and End views (the latter with rebound display).
TomoView is the perfect PC-based companion to the OmniScan family of instruments, and seamlessly imports OmniScan files for advanced processing and analysis in TomoView.
Displays volume-corrected views; views are fully customizable and come with several preconfigured templates.
Corrects potential operator errors in acquisition parameters (incorrect skews, index offsets, etc.) by reading back raw acquisition data without altering original data.
Imports and merges several OmniScan data files. For simplified interpretation, merges several groups into one.
Advanced Inspection ToolsTomoView offers advanced inspection tools to simulate, test, and prepare setups for the OmniScan.
2D matrix Pitch-and-catch, tandem Advanced focusing
Advanced Analysis Tools The TOFD Manager performs TOFD calibration,
lateral wave straightening, lateral wave removal, and the synthetic aperture focusing technique (SAFT).
C-Scan Merge: Merges C-scans based on minimum or maximum amplitude, or time-of-flight (TOF).
Signal-to-noise ratio (SNR): On a C-scan, this tool calculates and displays areas in which SNR is above and/or below a certain threshold.
ReportingCreating a report in TomoView takes just a few clicks. Defects can be added into the indication-table database, the indication table can be customized with additional readings, and you can add comments specific to each indication.
OmniScan Data Analysis and Reporting with TomoView
ReportingThe OmniScan MX2 is designed to inspect, analyze and generate reports directly on the instrument, or off-line on a computer.
The reports created on the OmniScan include an indication table that can be customized with additional readings and comments specific to each indication.
A high resolution image of the current display is included in the report when selected.
The auto-generated report contains relevant parameters for the instrument, software, calibration, UT parameters, phased array parameters, scanner setup, and flaw reporting.
Up to eight readings from the original setup can be displayed using the touch screens simple toggle operations.
Reports are stored and viewed on the instrument, and can also be saved as HTML documents for use on a computer.
Reports are fully customizable and come with several preconfigured templates.
2-D TRL phased array probe (multiple-line scan).
10 www.olympus-ims.com
Typical ApplicationsGirth Weld InspectionThe OmniScan PA is at the heart of the Olympus manual and semiautomated circumferential weld inspection solutions developed for the oil and gas industry. These phased array systems are certified to inspect tubes in compliance with ASME, API, and other code crite-ria. They offer superior inspection speed and detection, and facilitate the interpretation of indications.
Pressure Vessel Weld InspectionA complete inspection of pressure vessel welds can be performed in a single scan using an OmniScan PA and a motorized scanner such as the WeldROVER. By combining TOFD and PA in a single inspection pass, a significant reduction in inspection time can be achieved as compared with conventional raster scanning or radiography. Further-more, inspection results are available immediately, enabling you to detect problems with welding equipment and fix them right away.
Weld Inspection of Small-Diameter PipesWhen coupled with the COBRA manual scanner, the OmniScan flaw detector is capable of inspecting standard pipes ranging from 0.84in. OD to 4.5in.OD. With its very slim design, this manual scanner is capable of inspecting pipes in areas with limited access. Adjacent obstructions such as piping, supports, and structures can be as close as 12mm (0.5in.).
Manual and Semi-Automated Corrosion Mapping The OmniScan PA with the HydroFORM scanner is designed to offer the best inspection solution for detecting wall-thickness reductions resulting from corrosion, abrasion, and erosion. In addition, this system detects mid-wall damage, such as hydrogen-induced blistering or manufacturing-induced laminations, and easily differentiates these anomalies from loss of wall thickness. In this application, phased array ultrasound technology offers superior inspection speed, data point density, and detection.
Composite InspectionParts made of laminate composite materials pose an inspection chal-lenge due to their various shapes and thicknesses. Olympus offers complete solutions for the inspection of carbon fiber reinforced polymer structures. These solutions are based on the OmniScan flaw detector, the GLIDER scanner, and dedicated probes and wedges designed for CFRP flat panel and radius inspection.
Compatible with the Following Inspection Codes:The OmniScan MX2 is compatible with standard industry inspection codes, including, but not limited to:
ASME Section V, Article 4 AWSAll ASME phased array code cases API 1104 and API RP2XASTM E2700-09 CEN EN 583-6ASTM 2591 BSI BS7706ASTM E2491-06 and more
11
OmniScan MX2 Mainframe SpecificationsOverall dimensions (W x H x D)
325 mm x 235 mm x 130 mm (12.8 in. x 9.3 in. x 5.1 in.)
Weight 5 kg (11 lb), including module and one battery
Data StorageStorage devices
SDHC card, most standard USB storage devices, or fast Ethernet
Data file size 300 MB
I/O PortsUSB ports 3
Speaker out Yes
Video output Video out (SVGA)
Ethernet 10/100 Mbps
I/O LinesEncoder
2-axis encoder line (quadrature, up, down, or clock/direction)
Digital input 4 digital TTL inputs, 5 V
Digital output 4 digital TTL outputs, 5 V, 15 mA
Acquisition on/off switch
Remote acquisition enabled TTL, 5 V
Power output line5 V, 500 mA power output line (short-circuit protected)
Alarms 3 TTL, 5 V, 15 mA
Analog output 2 analog outputs (12 bits) 5 V in 10 k
Pace input 5 V TTL pace input
DisplayDisplay size 26.4 cm (10.4 in.) (diagonal)
Resolution 800 pixels x 600 pixels
Brightness 700 cd/m2
Number of colors 16 million
Type TFT LCD
Power SupplyBattery type Smart Li-ion battery
Number of batteries1 or 2 (battery chamber accommodates two hot-swappable batteries)
Battery life Minimum 6 hours with two batteries
Environmental SpecificationsOperating temperature range
0C to 45C; 0C to 35C with 32:128 PA (32F to 113F; 32F to 95F with 32:128 PA)
Storage temperature range
20C to 60C (4F to 140F) with batteries20C to 70C (4F to 158F) without bat-teries
Relative humidity0% to 85% noncondensing No air intake; designed for IP66
Shockproof rating Drop tested according to MIL-STD-810G 516.6
Phased Array Module Specifications (Applies to OMNI-M-PA16128*)Overall dimensions (W x H x D)
244 mm x 182 mm x 57 mm (9.6 in. x 7.1 in. x 2.1 in.)
Weight 1.2 kg (2.6 lb)
Connectors1 OmniScan connector for phased array probes 2 BNC connectors for UT probes
Number of focal laws 256
Probe recognition Automatic probe recognition
Pulser/ReceiverAperture 16 elements
Number of elements 128 elements
PulserVoltage 40 V or 80 V per element
Pulse width Adjustable from 30 ns to 500 ns, resolution of 2.5ns
Pulse shape Negative square wave
Output impedance Less than 25
ReceiverGain 0dB to 74 dB, maximum input signal 1.32Vp-p
Input impedance 75
System bandwidth 0.75MHz to 18 MHz (3 dB)
BeamformingScan type Sectorial and linear
Group quantity Up to 8
Active elements 16*
Elements 128
Data AcquisitionDigitizing frequency 100 MHz (10 bits)
Maximum pulsing rate Up to 10 kHz (C-scan)
Data ProcessingNumber of data points Up to 8,000
Real-time averaging 2, 4, 8, 16
Rectifier RF, full wave, halfwave +, halfwave
FilteringLow-pass (adjusted to probe frequency), digital filtering (bandwidth, frequency range)
Video filtering Smoothing (adjusted to probe frequency range)
Data VisualizationA-scan refresh rate Real time: 60 Hz
Data SynchronizationOn internal clock 1 Hz to 10 kHz
On encoder On 1 or 2 axes
Programmable Time-Corrected Gain (TCG)Number of points 16 (1 TCG curve per channel for focal laws)
AlarmsNumber of alarms 3
Conditions Any logical combination of gates
Analog outputs 2* Models 16:16, 16:16M, 16:64, 16:64M, 32:32, and 32:128 also available.
OmniScan MX2 Specifications
48 Woerd Avenue, Waltham, MA 02453, USA, Tel.: (1) 781-419-390012569 Gulf Freeway, Houston, TX 77034, USA, Tel.: (1) 281-922-9300
505, boul. du Parc-Technologique, Qubec (Qubec) G1P 4S9, Tel.: (1) 418-872-11551109 78 Ave, Edmonton (Alberta) T6P 1L8
OmniScan_MX2_EN_201105 Printed in the USA Copyright 2011 by Olympus NDT.*All specifications are subject to change without notice. All brands are trademarks or registered trademarks of their respective owners and third party entities.
www.olympus-ims.com
info@olympusNDT.com
isISO9001and14001certified.
Global Presence, Local AssistanceOlympus has an extensive network of direct sales branches and representatives located in many industrial regions around the world. Answers to your questions on products, applications, training, and technologies are just one phone call or e-mail away from our dedicated staff members.
Customer ServiceOlympus is committed to providing the best technical support and after-sales service to reliably meet your needs in a prompt and support-ive fashion. Our professionally staffed service centers are dedicated to helping customers with repair or calibration throughout the life cycle of equipment.
Olympus NDT Training AcademyThe unique Olympus NDT Training Academy offers comprehen-sive courses in phased array technology and applications. Courses range from a two-day Introduction to Phased Array program to a two-week, in-depth Level II Phased Array course. In all cases, students experience practical training using the portable OmniScan phased array unit.
Courses are currently being offered at the training facilities of participating companies, in addition to customer-determined locations worldwide. Customized courses can also be arranged.
Web Based TutorialThe tutorial offered by Olympus provides a basic introduction to the main theories used to make our instruments. These tutorials also present typical applications pertain-ing to the various markets in which Olympus instruments are used.
Phased Array Testing Field GuideOlympus new Phased Array Testing field guide is a convenient resource for customers and anyone else interested in phased array technology. It is designed to be an easy-to follow introduction to ultrasonic phased array testing, both for newcomers and more experienced users who wish to review the basic principles. This guide begins by explaining what phased array testing is and how it works, outlines some considerations for select-ing probes and instruments, and con-cludes with further reference information and a phased array glossary.
This free field guide can be obtained from your local sales representative.
Understanding Phased Array Technology Poster
To support the growing NDT community, Olympus has published the Understanding Phased Array Technology post-er. This poster was designed by field experts to present phased array inspection technology in a concise and clearly illustrated manner.
This free poster can be obtained from your local sales repre-sentative, or directly from our website.
NDT Field Guides
Phased Array Testing
Basic Theory for
Industrial Applications
Copyright 20062009 by Olympus
NDT. All rights reserved.
920-172A_EN - Poster_PA_EN_2009
06
RA, PA, DA, and SA readings allow the
user to accurately
position the defect in real time during
an inspection.
RA: Reference point to the indication i
n gate A
PA: Probe front face to the indication in
gate A
DA: Depth of the indication in gate A
SA: Sound-path length to the indicatio
n in gate A
For manual inspections, real-time read
ings are essential to quickly position
the reflected signal source with
respect to the part geometry and/or p
robe location.
PA
SA
DA
RA
Top
Bottom
Top45
T1
B0
Distance-amplitude curves (DAC) use
d to create
the time-corrected gain (TCG)
www.olympus-ims.com The leader i
n phased array technology for more t
han a decade
PA probeDelay (ns)
Angle steering
Incident wave front
t0t1t2t3tn
Acquisition time
EmissionReception
Pulse-echo
=PA probe
Delay (ns)
Transmitting
delays
Receiving delays
and sum
Probe elements
Pulses
Incident wave front
Reflected wave front
Trigger Flaw
Flaw
Echo signals
Emitting
Acquisition unit
Receiving
Phased array unit
e
g p
A
n = 8Wpassive
Scanning direction
Active group128
1
16
Electronic linear scanning
With electronic scanning, a single foca
l law is multiplexed across
a group of active elements; scanning
is performed at a constant
angle and along the phased array pro
be length (aperture). This
is equivalent to a conventional ultraso
nic transducer performing
a raster scan for corrosion mapping o
r shear-wave inspection. If
an angled wedge is used, the focal law
s compensate for different
time delays inside the wedge.
Sectorial scanningWith sectorial scan
ning (also called azimuthal or angular
scanning), the beam is moved through
a sweep range for a
specific focal depth, using the same el
ements; other sweep
ranges with different focal depths ma
y be added. The angular
sectors may have different values.
Dynamic depth focusing
Dynamic depth focusing (DDF) is a pro
grammable, real-time array
response-on-reception accomplished
by modifying the delay,
gain, and excitation of each element as
a function of time. DDF
replaces multiple focal laws for the sam
e focal range created by
the emitted beam with separate focuse
d beams at the receiving
stage. In other words, DDF dynamically
changes the focal distance
as the signal returns to the phased arra
y probe. DDF significantly
increases the depth of field and signal-
to-noise ratio.
Scanning Patterns
Phased Array Probes
Linear arrays are the most commonly
used phased array probes for industri
al applications. Thus, one of
the important features of linear arrays
is the active probe aperture.
The active aperture (A) is the total activ
e probe length. Aperture length is given
by the following formula:
A = (n 1) p + ewhere n = Numbe
r of elements in the PA probe
p = Elementary pitchdistance betwe
en the centers of
two adjacent elements
e = Element widthwidth of a single pi
ezocomposite
element (a practical value is e < /2)
g = Gap between adjacent elements
= v f
where = Wavelength
v = Material sound velocity
f = Frequency
understanding
Linear
Convex
Skewing
1.5-D array
Concave
Variable angle
2-D array
Annular
Dual linear
Internal focus
Dual 1.5-D
Phased array probes are made in a var
iety of shapes and sizes for
different applications. A few types are
illustrated here:
Types of ProbesAngle Beam
Angle beam probes are used with a
removable or integrated wedge to tran
smit
a refracted shear or longitudinal wave
into
a test piece. They are designed for a w
ide
range of applications and can be used t
o
vary the refracted beam angle or the sk
ew
of the beam, depending on the wedge
orientation. The probe face is acoustica
lly
matched to the wedge material.
Integrated Wedge
This variation of an angle beam probe
integrates the wedge into the probe
housing. The wedge configuration is fi
xed
but offers smaller overall dimensions.
Near Wall
The near wall probe is specifically desig
ned
to minimize the dead zone at probe end
s
by reducing the distance between the l
ast
available element and the external edge
of
the housing. This probe type is useful fo
r
composite radius and corner inspection
s,
or any application requiring close cont
act
to a wall using a 0 wedge.
Immersion
Immersion probes are designed to
be used with a water wedge or in an
immersion tank when the test part is
partially or wholly immersed. The wat
er
acts as a uniform couplant and delay
line.
Immersion probes are longitudinal-w
ave
probes that can be set up for refracte
d
shear-wave inspection under water.
Immersion probes are mostly intende
d
for automated inspections.
2-D and 1.5-D Arrays
Two-dimensional arrays have multiple
strips of linear arrays to allow electron
ic
focusing and steering in both probe
axes. 2-D arrays have the same numbe
r
of elements in both dimensions,
whereas 1.5-D identifies probes with
any combination of uneven numbers
of
elements. The probes can be used for
achieving optimal focusing capability
or
to cover a defined area without probe
movement.
Dual ArraysTwo linear or two 1
.5-D array probes can
be positioned on a roof-angled wedge
with a transmitting probe. The probe
is
paired with a receiving equivalent for
optimal performance in noisy materia
ls
such as austenitic steel. This configura
tion
is a phased-array equivalent to a dual
-
element probe in conventional UT an
d
is widely used in the power-generatio
n
industry.
Basic ConceptsThe distinguishing
feature of phased array ultrasonic tes
ting is the computer-controlled excitat
ion (amplitude
and delay) of individual elements in a
multielement probe. The excitation of
multiple piezocomposite elements
can generate a focused ultrasonic beam
with the possibility of dynamically m
odifying beam parameters such as
angle, focal distance, and focal spot si
ze through software. To generate a be
am in phase by means of constructive
interference, the various active transd
ucer elements are pulsed at slightly d
ifferent times. Similarly, the echo from
the desired focal point hits the variou
s transducer elements with a computa
ble time shift. The echoes received by
each element are time-shifted before
being summed together. The resulting
sum is an A-scan that emphasizes the
response from the desired focal poin
t and attenuates echoes from other po
ints in the test piece.
Examples of focal laws
Delay (ns)
Incident wave front
PA probe
Defect Positioning
Acquisition without DDF Ac
quisition with DDF
Illustration of beam focusing
Illustration of beam steering
0
20
40
60
80
100
120
140
0 4 8 12 16
20 24 28 32
Element number
Tim
e d
elay
[ns]
FD = 15
FD = 30
FD = 60
FD = 15
FD = 30
FD = 60
Delay values (left) and depth scanning
principles (right) for a 32-element line
ar
array probe focusing at 15-mm, 30-mm
,
and 60-mm longitudinal waves.
Electronic linear scanning
Sectorial scanning
Olympus NDT Training Academy
Phased array training is available from
professional companies.
Visit www.olympus-ims.com
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Time-Corrected Gain
In order to cover the whole volume of
the part with
consistency, each focal law has to be c
alibrated for
attenuation and beam spread. This tim
e-corrected-
gain (TCG) calibration can be perform
ed with a
calibration block having several ident
ical reflectors
(for example, side-drilled holes) at dif
ferent depths.
Using a sectorial scan, the probe is mo
ved back
and forth so that each beam hits each
reflector. The
amplitude of each signal is recorded (
DAC) and
used to construct one TCG curve per f
ocal law.
Once the TCG calibration is completed
, each focal law has one individual TCG
curve. As
a consequence, a reflector will always
yield the same signal amplitude, regar
dless of its
position inside the part and of the be
am that detected it. A defect at 3 mm i
n depth detected
with an angle of 45 degrees will provi
de the same signal amplitude as if it w
ere at 10 mm and
detected at 60 degrees.