On October 1-4, 2023 OKOndt GROUP attended Railway Interchange 2023 - the largest North American railway event. This time the exhibition took place in Indianapolis, Indiana, USA (Indiana Convention Center) and brought together over 700 exhibitors and more than 8, 000 visitors who are the major influencers in the industry. Thank you to everyone who was with us at the RI 2023!



TOFD 2.2 PRO ultrasonic weld testing equipment

TOFD method has been widely used for fast and reliable ultrasonic testing (UT) of welded joints over the last years. TOFD offers great accuracy for measuring the critical size of crack-like-defects. The accuracy of better than ±1mm can be achieved in a wide range of material thicknesses.

“TOFD 2.2 PRO System” performs mechanized UT of butt welds using Time-Of-Flight Diffraction (TOFD) technique. The Equipment is used for testing the welded joints UT at:

  • flat objects;
  • tubes of medium and large diameters – OD not less than 12 in (300 mm) – depends on the scanner type;
  • spherical and cylindrical oil and gas tanks – OD not less than 33 ft (10 m).

Wall thickness: from .25 to 12 in (6 to 300 mm). Profile types: CRC Evans, single J groove weld, single V groove weld, double V groove weld, X welds, etc.

TOFD testing

TOFD testing

Key Features:

  • Quick, accurate and highly reproducible welds inspection.
  • Wireless operation. NDT inspector with a data acquisition PC can be situated anywhere inside Wi-Fi range.
  • Ultrasonic weld tester can work with any type of Windows based computer: Laptop, Desktop, Tablet, etc. Interface is both mouse- and finger-friendly.
  • Choose, not setup! - Really quick and comprehensive setup due to the elements libraries: Geometry library, Materials library, Scanners library, Probes library, etc.
  • Automated water supply individually under each probe.
  • Electronics is protected against fall down by scanner design.

Main advantages of TOFD are:

  • Detects defects regardless their orientation, in contrast to the pulse echo technique
  • In contrast to the radiography method, planar defects and cracks, which are not perpendicular to the measured surface can be detected
  • High degree of repeatability
  • Precise defect sizing capability
  • Fast scanning only along the weld. Full volume inspection in a single run.
  • Immediate results and permanent digital records with graphic images
  • Amplitude insensitive – acoustical coupling less critical
  • Set-up independent of weld configuration

TOFD 2.2 PRO Scanner is compact and reliable equipment, which assures stable scanning results. Such NDT instrument is most often used as ultrasonic pipe testing equipment. Magnetic wheels and spring loaded probes carriers with self-positioning system ensure transducers stability on the object surface which results in good coupling necessary for testing results reliability. Scanner is easy to drive and doesn’t fall from the object even when upside-down. Scanner carries TOFD Ethernet module, Wi-Fi module, and rechargeable battery pack. Cases of TOFD module and battery pack are shockproof. All equipment has protection rating IP65. Scanner design ensures that at fall down, the main impact will come to the scanner structure elements saving electronics. Storage battery ensures 8 hours of TOFD 2.2. PRO system operation. But it can be replaced with a single hand in several seconds if necessary.

TOFD systems software consists of the queue of tabs guiding the inspector through step-by-step setup procedure, data acquisition and analysis. Software is both mouse and finger friendly so can be used on various types of computers – tablets, laptops, desktops, monoblocks, etc. Setup process is greatly facilitated due to wide usage of setup elements libraries – Geometry library, Materials library, Scanners library, Probes library, etc. So, the major portion of the setup procedure shrinks to choosing of proper elements from those libraries. Complete setup packs suitable for particular testing tasks can be saved and then loaded at any time.

Main software functions are distributed among the following tabs:

«Object» tab:

  • selecting the test object geometry and setting up its dimensions;
  • selecting the test object material;
  • selecting the type of a weld bevel and setting up all its dimensions.


«Scanner» tab:

  • selecting the scanner;
  • setting up the scanner type: manual, motor-operated;
  • setting up the spatial position of TOFD transducers pairs relative to the origin of the coordinate system;
  • using of up to 4 TOFD transducer pairs;
  • carrying out encoder calibration.

«TOFD setup» tab:

  • selecting the type of TOFD probes, TOFD wedges, or setup of their parameters;
  • setting up the PCS – the distance between the index points of TOFD transducers and their shift relative to the welded joint axis;
  • calculation and graphic display of the following parameters using TOFD Calculator:
    • Spatial resolution (R);
    • Scanning-surface dead zone (D);
    • Backwall dead zone (D);
    • Locus curve;
    • Beam Spread.
TOFD setup

TOFD Calibration

«TOFD Calibration» tab:

  • setting up the main UT parameters;
  • carrying out the real-time TOFD calibration;
  • real-time checkup of reflectors detection in calibration block;
  • saving the calibration results.

«Data acquisition» tab:

  • A-Scan + TOFD-Scan display during the testing process;
  • carrying out the testing and data acquisition;
  • displaying the current scanner position and the scanning speed;
  • data synchronization by lateral wave during the testing process;
  • considering the scanning direction and capability to rescan the regions with the acoustic coupling loss;
  • saving the testing results.
Data acquisition

Data analysis

«Data analysis» tab:

  • review and analysis of saved data in a form of А-Scans and TOFD-Scans;
  • quick and detailed analysis of testing results using two measuring gates (type: normal, hyperbolic, manual hyperbolic);
  • for all indications, the following parameters can be measured:
    • their position in the object (X and Y-coordinates);
    • their length (ΔX);
    • their depth and height (Z, ΔZ);
    • their type: “volumetric”, ˝top-surface breaking˝, ˝bottom-surface breaking˝ or ˝inner˝;
  • building the defects table and its saving.

«Reports» tab:

  • Sorting and filtering of testing results in the database;
  • TOFD scan scaling for printout;
  • Reports preview;
  • Reports printing.

tofd transduser

  1. Transmitter;
  2. Receiver;
  3. Wedges;
  4. Internal crack.
  1. lateral wave;
  2. back wall echo;
  3. diffracted signal from the top tip;
  4. diffracted signal from the bottom tip.

TOFD transducers specification:

Catalog number Frequency, MHz Element dia. Object thickness
mm in mm in
TWS10-3-TOFD 3/8" 10 3 .125 10-15 .390-.600
TWS10-6-TOFD 3/8" 10 6 .250 15-35 .600-1.4
* TWS5-6-TOFD 3/8" 5 6 .250 15-50 1.4-2.0
TWS5-12-TOFD M16 5 12 .500 50-100 2.0-4.0
TWS3-12-TOFD M16 3 12 .500 100-200 4.0-8.0
TWS2.5-12-TOFD M16 2.5 12 .500 200-300 8.0-6.0
TWS2.25-12-TOFD M16 2.25 12 .500 200-300 8.0-6.0
TWS3-8-TOFD M16 3.0 8 .325 100-200 4.0-8.0
TWS2.5-8-TOFD M16 2.5 8 .325 100-200 4.0-8.0
TWS2.25-8-TOFD M16 2.25 8 .325 100-200 4.0-8.0


TOFD wedges specification:

Catalog number Refracted angleo
WS45 L-3/8"-TOFD 45
WS50 L-3/8"-TOFD 50
WS60 L-3/8"-TOFD 60
* WS70 L-3/8"-TOFD 70
WS45 L-M16-TOFD 45
WS50 L-M16-TOFD 50
WS60 L-M16-TOFD 60
WS70 L-M16-TOFD 70

* included in basic delivery set

Unit connectors
Pulser and Receiver 2 × BNC
Sync input
Trigger output
Types Spike + SWP
Voltage (SWP) 20 V, 30 V, 50 V, 100 V, 150 V, 200 V, 250 V, 300 V
Energy (SWP) 20 ns to 500 ns with 10 ns step Manual & Auto modes
Voltage (Spike) Low: 50 V, High: 300 V
PRF from 15 to 6000 Hz
Range Up to 100 us
Delay Up to 100 us
Gain 0 to 110 dB, with 0.1 dB step
Max signal input 20 V p-p
Bandwidth 0.2 MHz - 27 MHz
Filters 1 MHz, 2-3 MHz, 4-5 MHz, 10 MHz, 15 MHz, Full band
Rectification Full Wave
Signal Average 2x / 4x / 8x / 16x / 32x

Basic delivery set:

  • TOFD 2.2 PRO scanner (with electronics, battery and transducers on board);
  • Software for MS Windows notebook/tablet;
  • Charger;
  • Manual guide (hard copy);
  • Hard case.

Available at option:

  • Rugged Notebook or Tablet PC with pre-installed TOFD Software;
  • Additional transducers (see tab "Transducers");
  • Portable water tank (16l/3,52gal) with motorized pump (2-4,5Bar);
  • Extra battery.


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