Any type of test performed on a material that does not permanently alter its physical, chemical, mechanical or dimensional properties is called non-destructive testing (END; in English, NDT, nondestructive testing). Non-destructive testing is opposed to destructive testing in that it involves imperceptible or no damage. The different methods are based on the application of physical phenomena such as electromagnetic, acoustic, elastic waves, emission "Emission (physics)") of subatomic particles, capillarity, absorption "Absorption (chemistry)") and any type of test that does not involve considerable damage to the sample examined.
The terms non-destructive inspection, non-destructive testing, non-destructive examination and non-destructive evaluation are commonly used synonymously.
In general, nondestructive testing provides less accurate data about the state of the variable to be measured than destructive testing. However, they are usually cheaper for the owner of the piece to be examined, since they do not involve its destruction. Sometimes, non-destructive tests only seek to verify the homogeneity and continuity of the analyzed material, which is why they are complemented with data from destructive tests.
The wide application of non-destructive testing methods on materials is summarized in the following three groups:
Background
Nondestructive testing has been practiced for many decades. There has been a record since 1868 when work with magnetic fields began. One of the most used methods was the detection of superficial cracks in railway wheels and axles. The pieces were immersed in oil, and then cleaned and sprinkled with a powder. When a crack was present, the oil that had leaked into the discontinuity wetted the dust that had spread, indicating that the component was damaged. This led to the formulation of new oils that would be used specifically to perform these and other inspections, and this inspection technique is now called penetrant testing (PT).
However, with the development of production processes, the detection of discontinuities was no longer sufficient. It was also necessary to have quantitative information on the size of the discontinuity, to use it as a source of information, in order to perform mathematical calculations and thus be able to predict the mechanical life of a component. These needs led to the emergence of Non-Destructive Evaluation (NDE) as a new discipline. As a result of this technological revolution, a series of events would arise in the field of PND that would establish its current condition.
Liquid Penetrant Testing (NDT)
Introduction
Any type of test performed on a material that does not permanently alter its physical, chemical, mechanical or dimensional properties is called non-destructive testing (END; in English, NDT, nondestructive testing). Non-destructive testing is opposed to destructive testing in that it involves imperceptible or no damage. The different methods are based on the application of physical phenomena such as electromagnetic, acoustic, elastic waves, emission "Emission (physics)") of subatomic particles, capillarity, absorption "Absorption (chemistry)") and any type of test that does not involve considerable damage to the sample examined.
The terms non-destructive inspection, non-destructive testing, non-destructive examination and non-destructive evaluation are commonly used synonymously.
In general, nondestructive testing provides less accurate data about the state of the variable to be measured than destructive testing. However, they are usually cheaper for the owner of the piece to be examined, since they do not involve its destruction. Sometimes, non-destructive tests only seek to verify the homogeneity and continuity of the analyzed material, which is why they are complemented with data from destructive tests.
The wide application of non-destructive testing methods on materials is summarized in the following three groups:
Background
Nondestructive testing has been practiced for many decades. There has been a record since 1868 when work with magnetic fields began. One of the most used methods was the detection of superficial cracks in railway wheels and axles. The pieces were immersed in oil, and then cleaned and sprinkled with a powder. When a crack was present, the oil that had leaked into the discontinuity wetted the dust that had spread, indicating that the component was damaged. This led to the formulation of new oils that would be used specifically to perform these and other inspections, and this inspection technique is now called penetrant testing (PT).
In 1941, the American Society for Non-Destructive Testing (ASNT) was founded, which is the largest technical society in the world for non-destructive testing. This society promotes the exchange of technical information on PND, as well as educational materials and programs. It is also the creator of standards and services for the qualification and certification of personnel who perform non-destructive testing, under the American scheme.
Below are a series of dates related to historical events, discoveries, advances and applications of some non-destructive tests.
The entity that brings together all duly constituted institutions is the International Committee on Non-Destructive Testing (ICNDT) based in Vienna.
Globalization in world markets has marked the development of non-destructive testing, which already has a reach in every corner of the planet, and currently there are non-destructive testing societies in most countries, such as the Argentine Society of Non-Destructive Testing (AAENDE), the Australian Institute for Non-Destructive Testing (AINDT), the Austrian Society of Non-Destructive Testing (OGFZP), the Belgian Association of Non-Destructive Testing (BANT), The Brazilian Society for Non-Destructive Testing (ABENDE), The Canadian Society for Non-Destructive Testing (CSNDT), The Chinese Society for Non-Destructive Testing (ChSNDT), The Mexican Institute of Non-Destructive Testing A.C. (IMENDE A.C.), Mexican Association of Non-Destructive Testing (AMEXEND A.C.).
Applications
Non-destructive testing is used in a variety of branches covering a wide range of industrial activities.
Methods and techniques
Contenido
La clasificación de las pruebas no destructivas se basa en la posición en donde se localizan las discontinuidades que pueden ser detectadas, por lo que se clasifican en:.
Superficial non-destructive testing
These tests provide information about the surface health of the inspected materials. Superficial PND methods are:.
In the case of using VT and PT, there is the limitation of detecting only superficial discontinuities (open to the surface); and with MT and ET you have the possibility of detecting both superficial and sub-surface discontinuities (those found below the surface but very close to it).
Volumetric non-destructive testing
These tests provide information about the internal health of the inspected materials. The volumetric PND methods are:.
These methods allow the detection of internal and subsurface discontinuities, as well as under certain conditions, the detection of surface discontinuities.
Non-destructive leak testing
These tests provide information on the degree to which fluids can be contained in containers, without escaping into the atmosphere or becoming out of control. The PND methods of airtightness are:.
However, with the development of production processes, the detection of discontinuities was no longer sufficient. It was also necessary to have quantitative information on the size of the discontinuity, to use it as a source of information, in order to perform mathematical calculations and thus be able to predict the mechanical life of a component. These needs led to the emergence of Non-Destructive Evaluation (NDE) as a new discipline. As a result of this technological revolution, a series of events would arise in the field of PND that would establish its current condition.
In 1941, the American Society for Non-Destructive Testing (ASNT) was founded, which is the largest technical society in the world for non-destructive testing. This society promotes the exchange of technical information on PND, as well as educational materials and programs. It is also the creator of standards and services for the qualification and certification of personnel who perform non-destructive testing, under the American scheme.
Below are a series of dates related to historical events, discoveries, advances and applications of some non-destructive tests.
The entity that brings together all duly constituted institutions is the International Committee on Non-Destructive Testing (ICNDT) based in Vienna.
Globalization in world markets has marked the development of non-destructive testing, which already has a reach in every corner of the planet, and currently there are non-destructive testing societies in most countries, such as the Argentine Society of Non-Destructive Testing (AAENDE), the Australian Institute for Non-Destructive Testing (AINDT), the Austrian Society of Non-Destructive Testing (OGFZP), the Belgian Association of Non-Destructive Testing (BANT), The Brazilian Society for Non-Destructive Testing (ABENDE), The Canadian Society for Non-Destructive Testing (CSNDT), The Chinese Society for Non-Destructive Testing (ChSNDT), The Mexican Institute of Non-Destructive Testing A.C. (IMENDE A.C.), Mexican Association of Non-Destructive Testing (AMEXEND A.C.).
Applications
Non-destructive testing is used in a variety of branches covering a wide range of industrial activities.
Methods and techniques
Contenido
La clasificación de las pruebas no destructivas se basa en la posición en donde se localizan las discontinuidades que pueden ser detectadas, por lo que se clasifican en:.
Superficial non-destructive testing
These tests provide information about the surface health of the inspected materials. Superficial PND methods are:.
In the case of using VT and PT, there is the limitation of detecting only superficial discontinuities (open to the surface); and with MT and ET you have the possibility of detecting both superficial and sub-surface discontinuities (those found below the surface but very close to it).
Volumetric non-destructive testing
These tests provide information about the internal health of the inspected materials. The volumetric PND methods are:.
These methods allow the detection of internal and subsurface discontinuities, as well as under certain conditions, the detection of surface discontinuities.
Non-destructive leak testing
These tests provide information on the degree to which fluids can be contained in containers, without escaping into the atmosphere or becoming out of control. The PND methods of airtightness are:.