TOMOSCAN FOCUS

• Control of beam angle, focal distance, and spot size

• Multiple-angle inspections with a single electronically controlled multielement probe

• Greater flexibility for the inspection of complex geometry

• High-speed scans with no moving parts

ULTRASONIC PHASED-ARRAY SYSTEM

Phased-array technology allows the generation of an ultrasonic beam with the possibility of setting the beam parameterssuch as angle, focal distance, and focal point size through software; furthermore, this beam can be multiplexed over a largearray. These capabilities open a series of new possibilities; for instance, it is possible to quickly vary the angle of the beam toscan a part without moving the probe itself; phased array also allows the replacement of multiple probes and even mechan-ical components. Inspecting a part with a variable-angle beam also ensures detection regardless of the defect orientationwhile optimizing signal-to-noise ratio. The Tomoscan FOCUS phased-array system offers the following capabilities:

• Software control of beam angle, focal distance, and spot size• Multiple-angle inspection with a single, small, electronically controlled, multi-

element probe• Greater flexibility for the inspection of complex geometry• High-speed scans with no moving parts

WHAT IS PHASED ARRAY?

Software Control of Beam Angle, FocalDistance, and Focal Spot Size

To generate a beam, the various probeelements are pulsed at slightly differenttimes. By precisely controlling thedelays between the probe elements,beams of various angles, focal distances,and focal spot sizes can be produced.The echo from the desired focal point

hits the various transducer elementswith a computable time shift. The sig-nals received at each transducer ele-ment are time-shifted before beingsummed up together. The resulting sumis an A-scan that emphasizes theresponse from the desired focal pointand attenuates various other echoesfrom other points in the material.

Multiple-Angle Inspection with a Single, Small, Electronically Controlled,Multielement Probe

A conventional UT inspection wouldrequire a number of different transduc-ers. A single phased-array probe can bemade to sequentially produce the vari-ous angles and focal points required bythe application.

Applied delay

Resulting wave surface

Angle steer ing

ADVANCED OPTIONS

Dynamic Depth Focusing

Another outstanding feature of R/D Tech’s FOCUS phased-array system isthe ability to dynamically focus the beam within a part, at the reception.

The image on the left shows the inspection of a standard calibrationblock with a normal transducer with a fixed focus set at around half depth.Compare this with the inspection of the same block but with dynamicfocusing (right). Dynamic focusing allows inspections of thick componentswith a single probe, with flaws in perfect focus regardless of the depth.

AcquisitionUnit

Phased ArrayUnit

ProbesPulses Incident wave front

Reflected wave front

"Trig"

AcquisitionUnit

Phased ArrayUnit

Flaw

Echo signals

• Emitting

• Receiving

A phased-array probe is typically a one- or two-dimen-sional array of small transducer elements. A few differ-ent probe types are illustrated here: rho-theta, circular,2D matrix, and linear.

ADVANTAGES OF PHASED ARRAY

FOCUS May Be Used with Any UT SystemThe FOCUS system may be used as the front end to any existing ultrasonic system. Once the probe’s firing and receptiondelays (focal laws) are programmed into FOCUS, a simple trigger to the system produces an amplified analog A-scan whichis fed directly into the input of a conventional UT system.

When using FOCUS as the front end with a non–R/D Tech UT system, phased-array parameters must be entered from astandard PC (laptop or tabletop) or any other computer equipped with either Ethernet® or a serial link.

FOCUS Is ExpandableFOCUS may be delivered in versions ranging from 8 to 128 channels. Expansion to a greater number of channels requiresthe simple installation of plug-in boards. Also note that multiple FOCUS systems can be used in parallel to increase the effec-tive number of active elements.

FOCUS may be directly connected to any ofR/D Tech’s Tomoscan products. When used withother UT system, however, a standard PC or anyother computer equipped with either Ethernet ora serial link is required for the setup of the vari-ous parameters.

SYSTEM CONFIGURATION

Inspection of Complex Shapes

The capacity to produce at will, andunder computer control, various beamangles and focal lengths can be used toinspect parts with complex shapes suchas turbine disc, turbine blade root, reac-tor nozzle, and other complex shapes.Note here the precise defect indicationshown on the top, side, and front viewof the root area of the blade.

High-Speed Scans with no Moving Parts

While phased array implies handling themany signals from multielement probes, itis important to note that the resulting sig-nal is a standard RF signal (or A-scan) com-parable to that of any conventional systemwith a fixed angle probe. This signal maybe evaluated, processed, filtered, andimaged as any A-scan from a conventionalUT system. B-scan, C-scan, and D-scan builtfrom the A-scan are also identical to that ofa conventional system. The difference isthat a multiple-angle inspection may behandled with a single probe.

Multiplexing also allows motionlessscanning. Here a focused beam is createdusing a few of the many transducer ele-ments of a long phased-array probe. Thebeam is then shifted (or multiplexed) to theother elements to perform a high-speedscan of the part with no transducer move-ment along that axis. More than one scanmay be performed with various inspectionangles. FOCUS can be used in a productionenvironment to greatly improve the inspec-tion speed, sensitivity, and resolution overconventional systems.

The principle can be applied to flat partsusing a linear phased-array probe or totubes and rods using a circular phased-array probe.

High-speed linear scan: FOCUS canalso be used to inspect flat surfaces suchas steel plates. Compared to a wide,single-element transducer, sometimescalled “paint brush,” phased-array tech-nology offers a much higher sensitivitydue to the use of a small focused beam.

Scanning direction

Active group

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A P P L I C A T I O N S

Electro-Resistance Welds (ERW)

This fully automated industrial system is developed to inspectlongitudinal welds on electro-resistance welded tubes atspeed of up to 1.1 m/s with an axial resolution of 2 mm.

Conventional ultrasound inspection of ERW seam weldsrequires the transducers to mechanically track the weld cen-terline, not an easy task. With the FOCUS phased-array sys-tem, this tracking is done electronically, with no movingparts. The beam is simply multiplexed within the probe array,and the beam inspects a wider area, still with a focalizedbeam. Each phased-array probe resting on either side of theweld consists of 128 elements and covers a 60° sector.

By simply changing the probe wedge, tubes with diame-ters from 1.5 to 4.5 in. can be inspected with the same setup,reducing costs and improving productivity.

Tubes, Bars, and Rods

R/D Tech can provide multiplexed phased-array ultrasoundsystem that produces a rotating ultrasound beam with nomoving parts, allowing the replacement of expensive andtroublesome rotating heads. This industrial system performsthe detection of longitudinal and transverse cracks anddimensional measurement of diameter and thickness in stain-less steel tubes. Changes in tube diameters and thickness canbe accommodated by software, eliminating the need forcostly mechanical adjustment.

• Inspection speed of up to 500 mm/s• Electronic scanning equivalent to 18,000 r/min• No moving parts, easy to adjust• Software-assisted calibration

Thick Aluminum Plates

Until the advent of phased array, the inspection of thick alu-minum plates required a multiprobe setup to ensure fulldepth coverage. This approach was slow and cumbersome.The use of a unique annular array probe, combined withdynamic depth focusing, greatly improves the inspection ofthick aluminum plates.

The phased-array probe generates a single beam enablingthe detection of flat-bottom holes located between 1.2 mmand 300 mm into the part. This beam is kept narrower than2.5 mm over this range.

• Single probe inspection• Only one A-scan for each mechanical position• Faster inspection, smaller files, faster analysis• Constant lateral resolution• Simplified mechanical setup

INDUSTRIAL INSPECTIONS

O F P H A S E D - A R R AWELD INSPECTION

Inspection of Welds

Beam multiplexing as well as beam steering can be appliedto the inspection of welds. Phased-array inspection canreplace dual-axis weld inspections with a single-axis inspec-tion, increasing inspection speed by a factor 10 or more.

The beam is multiplexed and its focal length dynamicallyadjusted for optimum focusing on the weld line at all times.Because the beam angle and focal length are controlled fromthe software, it is easy to adapt to various material, thickness,and weld profiles.

• Full weld coverage with focused beam• Better detectability, discrimination, and positioning of flaws• One-line scan results in faster acquisition• Simplified mechanical setup• Volume-corrected imaging

Thin Welds and Friction Stir Welds

The FSW technique has exceptional qualities when applied tothin aluminum, but the process may generate small, tightdefects.

Ultrasonic phased-array technology was chosen over stan-dard ultrasonic inspection technology as it has proven to bevery efficient in the inspection of FSW by allowing inspectionof the entire weld volume with a single line scan. A well-designed phased-array probe may be used to generate nar-rowly defined ultrasonic beams in the weld volume, therebygreatly increasing the SNR and the likelihood of detection ofsmall tight cracks. Inspection speed and data quality aresuperior in the thin aluminum plates over standard ultrasonictechniques, which would require multiple transducers andraster scanning. Flaw characterization and evaluation is sig-nificantly enhanced over available radiographic technologyas well.

In-plant vertical setup for 40-ftlong friction stir weldinspection.

Courtesy of Boeing

Pipeline Girth Welds

The inspection of pipeline girth welds using the PipeWIZARDultrasound system has already proven its numerous advan-tages over more traditional inspection methods:

• Elimination of radiation exposure • Excellent flaw depth measurement offering a significant

reduction in weld rework• Immediate feedback to welding team

R/D Tech reaffirms its technological leadership with theintroduction of the PipeWIZARD Phased Array inspection sys-tem. This cutting-edge system offers:

• Electronically adjustable beam angle and focusing• Easier and faster inspection setup • More compact probe pan with less probes, providing easier

handling and faster circumferential scans • Inspection of a weld in a single circumferential scan at

100 mm/s giving full inspection results in less than 3 minutes

Output display from weldinspection.

Y T E C H N O L O G YPOWER GENERATION

Blade Roots and Attachments

The turbine blade roots and attachments have very complexgeometry difficult to inspect with conventional UT tech-niques. In addition, the assembly of the complete turbineleaves very little access room. Using a small 32-elementphased-array transducer (10 x 7 mm) combined with a back-scattered diffraction technique, detection and sizing ofdefects are performed in situ.

R/D Tech has developed, jointly with Ontario Hydro, aphased-array technique to inspect the root area of turbineblades which does not require the removal of the blades fromthe disc.

• Detection of notches 2 x 0.5 mm• Sizing of 3 x 1 mm notch• S/N ratio from the end of the blade is better that 14 dB• Inspection speed: 30 min/blade• Shear waves from 0 to 60 degrees; longitudinal waves from

30 to 70 degrees with the same probe

Turbine Discs

Turbine disc inspection with conventional ultrasonic technol-ogy would require up to 60 different transducers in order toguarantee full coverage of the inspection area. The FOCUSphased-array system can perform the same inspection with asingle probe.

Two different areas are inspected: the bottom of the anti-rotation keyhole and the turbine disc flange. These inspec-tions were performed using the same scanner and transduc-er array.

Formal system and inspection method approval wasgranted by Électricité de France (EDF) in January 1994.

• TOFD phased-array and pulse-echo phased-array configurations

• Large refraction-angle range of phased-array probes allows full coverage of inspection area

• Beam spot of 10 mm with a focal length of 500 mm

Phased-array turbine disc inspection system.

Courtesy EDF and SGS QualitestFrance

11 angles

Wedge andPhased-Array

Probe

Pressure Vessel Nozzles

Complex shapes, such as nozzles, are difficult to inspect. Fullcoverage of the inner radius would require the use of manyconventional transducers and a raster scan over a complexshape. The FOCUS phased-array system can control thebeam angle, focal length, and focal spot of an ultrasoundbeam, allowing full coverage with a single array probe. Theuse of focused ultrasound beam also improves signal-to-noiseratio.

Because of this flexibility, the FOCUS is the tool of choicefor the inspection of complex geometry such as nozzle welds,primary pumps, and reactor penetrations.

• Full volume coverage with large range of refraction angle• Pulse-echo and TOFD configuration• Inspection of inner radius and weld• Focused beam with large sound path• Volumetric imaging

Multiple-angle nozzle inspectionwith phased array.

L–0 blade root inspection.Courtesy Ontario Hydro

Canada

TomoViewUltrasound Acquisition and Analysis SoftwareAll of R/D Tech ultrasound products, whether using phasedarray, ultrasound, or even EMAT, share the same data acqui-sition and analysis software. The software is PC-based andcan be used on standard PCs ranging from simple laptops topowerful multiprocessor workstations.Data Acquisition and Analysis

• Software setup and control of the phased-array system• Easy programmation of focal laws for sector, linear, and

depth scans, as well as dynamic depth focusing• Automatic volumetric settings• Real-time display of A-scans, B-scans, C-scans, and D-scans• Real-time display of phased-array sector scans• Real-time display of angle-corrected, top, side, and front

views from either A-scan, C-scan, or peak data• Real-time imaging on part drawing overlay• Analysis may proceed simultaneously with data acquisition• Measurement cursors and time-of-flight diffraction

measurement tools• Scanner control for automated inspections

Reporting and Data Exchange

• Many automatic data exchange and reporting tools• Data export in ASCII data formats (Mathworks’ Matlab)• Fully Windows® compatible

Phased-Array Simulation Software (PASS)PASS is a Windows-based software that performs simulationof the ultrasonic field generated by various types of phased-array or conventional UT transducers.

• Runs on Windows® 95 or Windows NT™• Imaging of top, side, and front views of beam energy distri-

bution for various 1D and 2D probe geometries• Amplitude plots of any beam section• Prediction of A-scan response to point-like defects• Design of focal laws based on probe geometry and desired

beam angle, focal spot, and focal distance• Design of probe geometry parameters (for linear array, circu-

lar array, rho-theta, 2D matrix, etc.)• Ability to run simulations for flat or cylindrical interfaces,

including user-designed wedges• Simulations of diffracted field for both L or T waves and for

both pulse-echo or tandem modes

This image uses afocal law generatinga 0° focalized beam.

Another focal law isused with the verysame probe togenerate a 30° Lwave with someparasitic side lobes.

This image shows theresulting beam usinga wedge to generatea focalized 45° Swave without sidelobes.

This figure shows aray tracing simulationshowing the actualpath of the soundbeam from eachindividual elementthrough the wedge,into the material,and to the focalpoint.

ACQUISITION, ANALYSIS, AND REPORTING SOFTWARE

PHASED-ARRAY PROBES

SOFTWARE AND PROBES

R/D Tech can design, test, and provideyou with a wide range of phased-arrayprobes and custom wedges.

These application-specific probeshave a range from 0.5 MHz to 18 MHzand may come with 16, 32, 64, or 128elements. Special probes may have upto hundreds of elements.

R/D Tech’s phased-array probes maybe medium- or high-damped, of theimmersion or contact type.

Simulation examples

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SYSTEM SPECIFICATIONS

Representatives Worldwide – Contact us for more information or to discuss your applications.Belgium, Canada, China, France, Germany, Greece, India, Italy, Japan, Korea, Slovakia, Sweden, Taiwan, The Netherlands, United Kingdom, and United States

E-mail: info@rd-tech.com • Web Site: www.rd-tech.com

R/D Tech Head Office 4495, boul. Wilfrid-Hamel Québec (Québec) G1P 2J7CanadaTel.: (1) (418) 872-1155 Fax: (1) (418) 872-5431

R/D Tech USA240 Bear Hill Road, Suite 104Waltham, MA 02154USA Tel.: (1) (781) 890-5901Fax: (1) (781) 890-5950

R/D Tech EuropeParc Club Orsay Université4, rue Jacques Monod91893 ORSAY CEDEXFranceTel.: (33) (0) 1 69 41 10 95Fax: (33) (0) 1 69 41 10 92

R/D Tech AsiaCity coopEsaka 303 17-37Enoki-cho Suita CityOsaka 564 JapanTel.: (81) (0) 66 339 0896Fax: (81) (0) 66 378 0686

R/D Tech and R/D Tech products are trademarks of R/D Tech inc. All other products are trademarks and registered trademarks of their respective owners.

GeneralSystem bandwidth (-3dB) 650 kHz–20 MHz Maximum pulsing rate 20 kHz, with or without change of the

focal lawsInspection modes Pulse echo or transmit/receive (dynamically

selectable). Note that twice the quotednumber of channels are available in trans-mit/receive mode.

Multiple probe capability The system supports up to 4 probes of32 elements in pulse-echo configurationor any combination of probes up to128 elements.

Dynamic range 56 dB/channelComputer interface Both RS232 and Ethernet standard. Direct

configuration from Tomoscan.Windows NT™–based software availablefor setup from computer. Custom inter-faces may be designed using standardremote procedure call (RPC) functions ordynamic link libraries (DLL).

Focal law storage Up to 1024 different focal laws can bestored for high-speed multiplexing.Independent focal laws may be used fortransmission and reception.

Power requirements 85–265 VAC 47–63 HzTemperature range 0°C–50°C

Pulser/ReceiverNumber of pulsers Configurations available with 8,16, 64, or

128 pulsersPulser delays Adjustable from 0 µs to 25 µs in

2-ns incrementsOutput impedance 6 ΩPulse output Amplitude adjustable from 50 V to 200 V;

pulse width adjustable from 20 ns to500 ns; fall time < 6 ns

Pulse type Negative square pulseNumber of receivers Configurations available with 8, 16, or

32 receivers (more in custom configurations)

Receiver delays Adjustable from 0 µs to 25 µs in 2-ns increments

Receiver DAC curves Up to 30 dB/µs on each element slopebefore summing

Receiver gain range 0–80 dB. Independent gain for eachreceiver and focal law.

Maximum input signal +10 dBm (2 Vpp) for each elementInput filters 4 user-selectable filter ranges: none,

500 kHz–5 MHz, 2 MHz–10 MHz, 5 MHz–15 MHz

Input impedance 50 ΩRF output +10 dBm in 50 Ω

Available ConfigurationsFOCUS may be tailored for specific applications. The various configurations are identified with a two-number suffix as follows:• The 1st number is the maximum number of simultaneously active drivers (8, 16, or 32 drivers) • The 2nd number is the total number of available connections for transducer elements (8, 16, 32, 64, or 128 elements)Example: A FOCUS 32/64 connects to up to 64 elements out of which up to 32 may be active at any time.

Please note that the systems may be expanded at any time up to the limit supported by the choosen housing with the simple addition of plug-inboards. Also note that while the maximum available configuration is FOCUS 32/128, custom configurations are also available with more channels.Multiple FOCUS systems can also be used in parallel to increase the number of active elements.

8-Channel Phased-Array EMAT SystemThis stand-alone phased-array EMAT system is driven by the same software than the regular phased-arraysystems. It can interface with either conventional EMAT probes or phased-array EMAT probes.

Number of P/R channels 4 or 8 channelsOutput impedance 10 ΩOutput voltage 1 kVpp (no load). Output current: 30 A with 22 Ω load.Receiver input impedance 50 ΩPower requirements 110/220 VAC, 50/60 Hz

Benchtop version48 cm x 39 cm x 18 cm, 22 kg32/128 max. configurationA 19 in. rack mount version is also available

Portable benchtop version36 cm x 36 cm x 16 cm, 12.2 kg16/64 max. configuration

S2000 version36 cm x 30 cm x 36 cm, 15 kg16/128 max. configuration