Non Destructive Techniques (NDT)
Authors: W.D. Dover, R. Collins, D. H. Michael
Ac-field measurement technique measures and interprets
field perturbations in a region containing a surface flaw.
ACPD, as it was originally called, has a long history of
malpractice but was so eminently suitable for laboratory
monitoring of fatigue cracks that it was reassessed for this
purpose. The technique consists of impressing an AC
current into the region containing the flaw and exploring
the surface—voltage distribution with a probe.
Initially edited in hard copy, this book was considered one
of the most relevant documents when published. Apart
from some new technologies that did not exist when it
was written, we can say that this document is still actual
and should be considered a reference
Authors: A.I.Bondarenko, E.O.Paton
Extended welded pipelines are characterized by the
presence of various discontinuities in them related to the
change of material density and/or cross-section of pipe
walls on their joint boundary and/or along the pipe
length. This paper deals with detecting these
discontinuities, with which low-frequency guided waves
of longitudinal and torsional modes interact during their
propagation in the form of a circular wave through the
pipe cross-section.
Author not indicated
Ultrasonic Testing (UT) uses high frequency sound energy
to conduct examinations and make measurements.
Ultrasonic inspection can be used for flaw
detection/evaluation, dimensional measurements, material
characterization, and more. To illustrate the general
inspection principle, a typical pulse/echo inspection
configuration as illustrated below will be used.
Author unknown
This presentation provides information on magnetic
particle inspection methods (MPI).
It can be used to teach divers on the purpose and
implementation of such procedures during mobilization
and maintenance. This document does not explain
underwater MPI.
Publisher: Mark Stephen Rogers
This presentation shows the applications, advantages and
disadvantages of various Non-Destructive Techniques
(NDT) used in multiple industries, particularly in the
offshore and petroleum industries.
Author: Micheal C. Smith
This document describes the inspection procedure to be
used with the Underwater ACFM instrument for manual
inspection with standard probes. These probes are
designed to be deployed by divers, with data collected
and sent to a controlling PC.
TSC Subsea is a company based in the UK
https://www.tscsubsea.com/contact/
This document can be classified under the “Technical
document - Vessels” rubric. Nevertheless, it provides
guidelines that can be used to organize inspections.
Publisher:
The american society for non destructive testing, inc.)
This training package provides essential knowledge of
radiography according to the American Society for
nondestructive testing (ASNT) requirements ( ASNT can be
contacted @ https://www.asnt.org/).
Author:
Reza K. Amineh, Maryam Ravan, Hesamedin Sadeghi, and
Rouzbeh Moini
In the alternative current field measurement (ACFM)
technique, the nonzero value of liftoff distance for the
magnetic sensor acts as a low-pass filter on surface crack
signals, causing errors in crack detection and sizing. The
authors present a blind deconvolution algorithm for Liftoff
evaluation and surface crack signal restoration.
Publisher:
The american society for non destructive testing, inc.)
This training package provides essential knowledge of
magnetic testing according to the American Society for
nondestructive testing (ASNT) requirements (ASNT can be
contacted @ https://www.asnt.org/)
Publisher: Siemens Rolling Stock Pvt. Ltd, Aurangabad
This presentation can be used to inform personnel on
ultrasonic testing
Publisher: International Atomic Energy Agency
Even though this document is not specifically designed for
diving activities, it provides essential information regarding
Eddy Current.
Publisher: Dzevad Hadzihafizovic
This handbook provides basic information about weld
conditions, gauges, symbols, and weld terms.
Authors:
Jasper A. Agbakwuru, Ove T. Gudmestad, John Groenli,
Helge Skjaveland
This paper demonstrates a technique for tracking and
identifying leaking points on pipelines installed in
unclear/muddy water conditions using optical cameras.
The method leads a remotely operated or hyperbaric
system to the leak in muddy water conditions for close
visual inspection and subsequent repair.
Publisher:
The american society for non destructive testing, inc.)
This book was previously published as Supplement to
Recommended Practice SNT-TC-1A (Q&A Book):
Ultrasonic Testing Method, first published in the 1980s. It is
based on previous Q&A Book editions.
Authors:
Ken Woolley, Tim Woolley, and Bruce Banfield
Since the beginning, underwater MPI has been carried by
night due to the inks' characteristics. New inks are now
available, although they are for topside use and thus are
not necessarily applicable to underwater conditions.
Recent trials have been conducted to determine the
suitability of available inks to increase white light levels
underwater. This paper presents the work and discusses
the findings, which have application worldwide.
Publisher: Frontline
This document provides procedures for visual and optical
inspection according to “Frontline”, a company specialised
in non destructive techniques
(https://frontlinetesting.com/ )
Authors: Restu Putra & Ahmad Irsyad
This presentation is another document that can be used to
initiate personnel to Eddy Current inspection.
Author: Mark W Hounslow
Particulate matter derived from various fuel combustion
sources contains minor to trace amounts of Fe-oxides that
magnetic measurements can detect. These magnetic
particulates can be used as proxies for particulate pollution
since oxide contents are often more significant in
quantities and may have distinctive magnetic properties
compared to most types of natural dust.
Author:
Ali Khaloo , David Lattanzi, Adam Jachimowicz, and
Charles Devaney
This paper presents a case study where photogrammetry
was used to create comprehensive and high-resolution
3D point clouds of a dam and surrounding environment
at intervals. These models were then assessed for their
quality and ability to resolve defects that were artificially
applied to the structure between inspection intervals. The
results indicate that the integrated process can generate
models that accurately render various defect types with
sub-millimeter accuracy.
Authors: Restu Putra & Ahmad Irsyad
This presentation is another document that can be used
to initiate personnel to Eddy Current inspection.
Publisher: International Atomic Energy Agency
Even though this document is not specifically designed for
diving activities, it provides essential information regarding
the use of NDT .
The organization for which it has been designed is proof
of quality.
This is another document from the International Atomic
Energy Agency, not specifically designed for diving
activities, that provides essential information regarding the
use of NDT.
Tomography is an x-ray technique in which shadows of
superimposed structures are blurred out by a moving x-ray
tube. This method is used in radiology, archaeology,
biology, atmospheric science, geophysics, oceanography,
plasma physics, materials science, astrophysics, quantum
information, and other areas of science.
This document is provided by the International Atomic
Energy Agency.
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Authors: Duje Medak, Luka Posilovic, Marko Subasic,
Marko Budimir, Sven Loncari
Most ultrasonic data collection has recently become
automated, but the analysis of this data is still done
manually. This makes it expensive, inconsistent, and prone
to errors. An automated system could make processes
much more efficient, but the current methods are not
effective. Deep learning could be a more effective
approach for analyzing this data, as it has been successful
in similar cases. Based on this, the authors utilized a deep
learning model called EfficientDet to automatically detect
defects in ultrasonic images.
Authors: Chao Chen, and Xingyuan Zhang
A support vector machine-based method is proposed to
solve the challenge of accurately quantifying surface
defect depth during laser ultrasonic inspection. A finite
element model for laser ultrasound inspection of
aluminum materials with surface defects was developed
using COMSOL software, based on the thermal-elastic
mechanism.
