Time of Flight Diffraction (ToFD) Course

Time of Flight Diffraction (ToFD) - Blended Learning Package

This eLearning training is part of the ‘blended learning’ ToFD package; a mix of eLearning and in-class practical training followed by certification to BS EN ISO 9712. The online modules can be studied when and where it is most convenient and at your own pace.

The package separates the learning of key concepts from the learning of a specific instrument, coupled with interactive exercises focused on the principles behind set-up, calibration, acquisition and data analysis. An intuitive logical training structure, which invariably helps the students understand key concepts, step-by-step.

In addition to the eLearning element of the Time of Flight Diffraction training, students will then attend practical classroom training for 5 days.

Note for candidates wishing to enrol on a course which includes blended learning: It is a mandatory requirement to issue access to the online material no less than 30 DAYS prior to the commencement of the in-class element of the course. There shall be no exception to this requirement, please plan your study to embrace this requirement.

The eLearning training course is divided in four modules:

Module 1: Basic Principles of Ultrasound and Ultrasound Testing
Module 2: Principles Underlying ToFD
Module 3: Data Analysis
Module 4: Review

Each module contains:

Pages explaining the underlying theory
Videos explaining the theoretical and practical aspects of Time of Flight Diffraction,
Silverlight interactive exercises in which the student can build a set-up, practice calibration and scanning and learn to evaluate real data
A test section for self-evaluation

At the end of your online training phase, an online test will enable you to decide whether you are ready for the classroom element of the course, or if you need further time to study.

Prices depend where you will be attending the last 5 days of the course - find out more.

When you have booked your online training, you will receive an email notification with your login details. You will then have 60 days from first login to complete your eLearning course.

Module 1: Basic Principles of Ultrasound and Ultrasound Testing

Non-Destructive Testing (NDT)
Sound versus ultrasound
Distance, velocity, cycle, material density
Sine wave, frequency, wavelength
dB system
The shell of an ultrasound instrument, ToFD probes, ToFD wedges
Pulser/receiver, square pulse
Wave propagation, scattering, absorption, energy spreading
Beam, sound field, beam diameter
Through transmission, pulse echo, angle beam, immersion, PAUT
A-Scan
Structure and qualification of a procedure, training, acceptance criteria
Calibration blocks, couplant
Marking on part, probe positioning
Naming files, storing data
Section's test

Module 2: Principles underlying ToFD

Butt welds
Digital instrument, pulser/receiver, digitizer, filters, gain
Probes, frequency spectrum, signal waveform
Wedges, hard wedges
Scanner, encoder
Huygens’ principle, diffraction
Snell’s law, incident vs. refracted, critical angles
ToFD A-Scan, phase shift, phase difference, averaging
PCS, transit time, depth calculation, height calculation, position uncertainty
Beam spread, beam spread in-wedge, beam spread in-part, frequency spectrum
Lateral wave, backwall, mode-converted backwall
Dead zones, accuracy, resolution
B-Scan, gray scale
Whisker effect, parabolic cursors
Non-parallel and parallel scans
Multiple scans
Influence of frequency on coverage, dead zones
Influence of wedge angle on time scale, coverage
Influence of PCS on dead zones, resolution, coverage
How to optimize the digitizing frequency, filters, averaging, time window, sensitivity, PRF
Calibration of the beam index point, velocity
Scanning speed
Wedge delay calibration, lateral wave straightening, lateral wave removal
Interactive exercises on set-ups, beam index point and velocity calibration, scanning
Interactive exercises on wedge delay calibration and lateral wave straightening
Section’s test

Module 3: Data Analysis

B-Scan perspective
Lateral wave, backwall and mode-converted backwall signals
Effect of beam spread on depth and the backwall signal
Indication classification, probe position vs. height, angle vs. height
Geometrical indications, double-V welds, pipes misalignment, different wall thickness
Data quality, calibration, basic analysis, detailed analysis
Signal start, grouping, point-like indications
Height and depth, top-surface breaking, bottom-surface breaking, embedded
Length and position, parabolic shape, elongated and curved
Interactive viewer, top-surface breaking, bottom-surface breaking, embedded
Interactive exercises on set-up, beam index calibration, scanning, data analysis
Section’s test

Module 4: Review

Hardware
Scans and views
Theory
Set-ups
Calibration
Data analysis
The defects

Time of Flight Diffraction (ToFD) Course

Time of Flight Diffraction (ToFD) - Blended Learning Package

Taster

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