Non-Destructive Diagnostic Methods for Fire-Side Corrosion Risk Assessment of Industrial Scale Boilers, Burning Low Quality Solid Biofuels—A Mini Review

The use of low-emission combustion technologies in power boilers has contributed to a significant increase in the rate of high-temperature corrosion in boilers and increased risk of failure. The use of low quality biomass and waste, caused by the current policies pressing on the decarbonization of the energy generation sector, might exacerbate this problem. Additionally, all of the effects of the valorization techniques on the inorganic fraction of the solid fuel have become an additional uncertainty. As a result, fast and reliable corrosion diagnostic techniques are slowly becoming a necessity to maintain the security of the energy supply for the power grid. Non-destructive testing methods (NDT) are helpful in detecting these threats. The most important NDT methods, which can be used to assess the degree of corrosion of boiler tubes, detection of the tubes’ surface roughness and the internal structural defects, have been presented in the paper. The idea of the use of optical techniques in the initial diagnosis of boiler evaporators’ surface conditions has also been presented.

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Bearing defect diagnosis and acoustic emission

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1243/135065003768618614 ◽

2003 ◽

Vol 217 (4) ◽

pp. 257-272 ◽

Cited By ~ 59

Author(s):

A Morhain ◽

D Mba

Keyword(s):

Acoustic Emission ◽

Threshold Level ◽

Diagnostic Methods ◽

Non Destructive Testing ◽

Test Rig ◽

Destructive Testing ◽

High Background ◽

Bearing Defect ◽

Non Destructive ◽

Ae Counts

Acoustic emission (AE) was originally developed for non-destructive testing of static structures, but over the years its application has been extended to health monitoring of rotating machines and bearings. It offers the advantage of earlier defect detection in comparison with vibration analysis. However, limitations in the successful application of the AE technique for monitoring bearings have been partly due to the difficulty in processing, interpreting and classifying the acquired data. The investigation reported in this paper was centred on the application of standard AE characteristic parameters on a radially loaded bearing. An experimental test rig was modified such that defects could be seeded onto the inner and outer races of a test bearing. As the test rig was adapted for this purpose, it offered high background acoustic emission noise providing a realistic test for fault diagnosis. In addition to a review of current diagnostic methods for applying AE to bearing diagnosis, the results of this investigation validated the use of r. m. s., amplitude, energy and AE counts for diagnosis. Furthermore, this study determined the most appropriate threshold level for AE count diagnosis, the first known attempt.

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Identification of structural defects in composite materials by the thermal imaging non-destructive testing method

MATEC Web of Conferences ◽

10.1051/matecconf/201929800119 ◽

2019 ◽

Vol 298 ◽

pp. 00119

Author(s):

Andrey Kokurov ◽

Igor Odintsev ◽

Boris Chichigin ◽

Dmitry Subbotin

Keyword(s):

Composite Materials ◽

Polymer Composites ◽

Thermal Imaging ◽

Structural Defects ◽

Non Destructive Testing ◽

Destructive Testing ◽

Testing Method ◽

Non Destructive ◽

Layered Polymer Composites

The article discusses the practical aspects of applying the thermal imaging non-destructive testing method of layered polymer composites. The specific purpose of the work is to demonstrate the possibilities of detecting in material and geometric identification of initial defects such as debonding.

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Non-invasive and non-destructive techniques in medicine and industry

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1979.0047 ◽

1979 ◽

Vol 292 (1390) ◽

pp. 137-146 ◽

Cited By ~ 1

Keyword(s):

Diagnostic Methods ◽

Non Destructive Testing ◽

Testing Methods ◽

Destructive Testing ◽

Non Invasive ◽

Clinical Methods ◽

Surveillance Method ◽

The Cost ◽

Non Destructive ◽

And Training

The paper deals with the question ‘What can industrial users of radiological and ultrasonic non-destructive testing methods learn from medical users of non-invasive diagnostic methods and vice versa?’ and similarly, 'What can designers of equipment for the two types of users learn from each other?’ It compares the requirements of each of the two disciplines: in medicine, as complementary to clinical methods; in industry, as a maintenance aid and as a surveillance method to assist design. The basis of the comparison is the purpose of the examination, the significance of the cost factor and the differing definitions of quality and safety. The paper also deals with the problem of cooperation and of ‘interfaces' between the various teams, a problem aggravated by different educational and training backgrounds of the various interdependent teams. The above comparison is set into a background of the evolution of the methods, and conclusions are attempted for the future.

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Dimensional effect when measuring Martens hardness

Bulletin of Kharkov National Automobile and Highway University ◽

10.30977/bul.2219-5548.2021.94.0.128 ◽

2021 ◽

pp. 128

Author(s):

Vasyl Moshchenok ◽

Lyidmila Kostina ◽

Denis Pluzhnikov

Keyword(s):

Service Life ◽

Functional Dependence ◽

Test Method ◽

Structural Defects ◽

Non Destructive Testing ◽

Destructive Testing ◽

High Productivity ◽

Dimensional Effect ◽

Meyer Equation ◽

Non Destructive

One of the most common methods of non-destructive testing, hardness testing, is used to evaluate the properties of materials. This is due to the ease of measurement and testing of the finished part, which will be used in the future, high productivity of the method, the ability to assess other mechanical properties of the material: elasticity, creep, tensile strength. An important aspect in the study of the hardness using in the range the Berkovich and Vickers indenters, which are more consistent with non-destructive testing, while the methods of Brinell and Rockwell leave quite large deformations, in our opinion, which further promote the development of structural defects and reduce the service life, which are not acceptable in critical products. Due to the improvement of product manufacturability, more and more manufacturers are trying to minimize the size of the part, while increasing their performance by applying a reinforced layer, which, in turn, should seek to reduce the thickness with increased service life. It is also impossible to study the hardness of very small products in the micro range due to the large mismatch between the dimensions of the product under test and the test method. In our opinion, the study of hardness by the Berkovich method in comparison with the Vickers method is more expedient for use with the same physicochemical properties of the material because of a larger scatter of hardness values between the compared methods, although they should be almost the same, with a small difference. An important omission to a certain year was the dimensional effect. Goal. The aim of the study is to assess the nature of the change in hardness with increasing load on the indenter, using the functional dependence of the hardness on the depth of the indenter. For this purpose, it is necessary to establish such connection for an indenter of various geometry. In this regard, we consider it appropriate to check the validity of the Meyer equation, which relates the load to the size of the imprint, for different indenters and materials. Results. When the hardness is calculated according to the Martens scales, the Vickers and Berkovich indenters are applied to the function of the surface area of the working part of the tip. An important factor of the consistency of the results in the increase in hardness is the small effect. The reasons for this can be very negligible. The sizeable effect is significantly infused into the results of increasing hardness, changing from 2,5 to 3,0 folds.

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Pile quality assessment by vibroacoustic method

E3S Web of Conferences ◽

10.1051/e3sconf/202021202010 ◽

2020 ◽

Vol 212 ◽

pp. 02010

Author(s):

Sergey Leonovich ◽

Nely Budrevich ◽

Ping Lyu ◽

Jijun Miao

Keyword(s):

Diagnostic Methods ◽

Non Destructive Testing ◽

Testing Methods ◽

Destructive Testing ◽

New Production ◽

Large Cities ◽

Steady Growth ◽

Entire Structure ◽

Production Technologies ◽

Non Destructive

In recent years, there has been a steady growth in industrial and civil construction, especially in large cities. Construction is often carried out in increasingly difficult geotechnical and hydrogeological conditions. This contributes to the emergence of new production technologies and diagnostic methods. The use of non-destructive testing methods allows you to quickly obtain information about various characteristics of an object without disrupting the process of its operation. This is especially true for hidden work, since access to the research object is practically closed, and its opening may entail undesirable consequences for the operation of the entire structure.

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Thermal Non-Destructive Testing for the Titanium Implants

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.785-786.52 ◽

2013 ◽

Vol 785-786 ◽

pp. 52-57 ◽

Cited By ~ 1

Author(s):

Qi Fang Zhu ◽

Ze Ming Sun ◽

Tong Da Ma ◽

Pu Li ◽

Dong Hui Zhang ◽

...

Keyword(s):

Processing Technique ◽

Titanium Implants ◽

Structural Defects ◽

Test Results ◽

Non Destructive Testing ◽

Destructive Testing ◽

Bottom Hole ◽

Hole Defects ◽

Non Destructive ◽

Data Processing Technique

Active thermal NDT is a promising technique for the detection of structural defects in solids. In this paper, the results of the first-stage research devoted to infrared thermographic detection of cracks in titanium alloys are presented. The test results obtained show that the Fourier analysis is a convenient data processing technique in active thermal NDT. Images of phase are more noise-resistant and able to reveal deeper defects compared to images of amplitude. In application to the inspection of bottom-hole defects in 9.6 mm-thick Ti6Al4V titanium alloy samples, it has been found that a minimum detected defect should have diameter from one to two times greater than its depth.

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Conclusive Determination of Compliance with the Prescribed Reinforcement Elements of Concrete Structures - The Appropriate Methods and their Capabilities

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.776.76 ◽

2018 ◽

Vol 776 ◽

pp. 76-80 ◽

Cited By ~ 2

Author(s):

Ondřej Anton ◽

Tereza Komárková ◽

Věra Heřmánková

Keyword(s):

Concrete Structures ◽

Structural Defects ◽

Non Destructive Testing ◽

Destructive Testing ◽

Current State ◽

Electromagnetic Methods ◽

Technical Solutions ◽

Non Destructive ◽

Physical Principles

Despite efforts to maintain quality during the construction of reinforced concrete structures, it is relatively common for improper reinforcement to be used, contradicting the project, which can lead to serious structural defects. It is then up to non-destructive testing methods to prove these defects. The key is the choice of the appropriate method and equipment, both in terms of achieving the necessary results and the possibility of their documentation. In recent years, there has been a significant progress in the development of non-destructive methods for the diagnosis of reinforcement and modernization of the technologies used so far, especially in the field of GPR and electromagnetic methods. At the same time, however, for a number of reasons, major limitations appear in the area of a conventional method of radiography. This contribution focuses on the current state of the problem, and it demonstrates the applicability of individual methods and their limitations given by their physical principles and technical solutions on a set of practical examples.

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Non-destructive and semi-destructive diagnostics of concrete structures in assessment of their durability

Bulletin of the Polish Academy of Sciences Technical Sciences ◽

10.1515/bpasts-2015-0010 ◽

2015 ◽

Vol 63 (1) ◽

pp. 87-96 ◽

Cited By ~ 32

Author(s):

J. Hoła ◽

J. Bień ◽

Ł. Sadowski ◽

K. Schabowicz

Keyword(s):

Structural Integrity ◽

Concrete Structures ◽

Test Methods ◽

Diagnostic Methods ◽

Test Results ◽

Non Destructive Testing ◽

Destructive Testing ◽

Comprehensive Classification ◽

Non Destructive

Abstract This paper proposes a comprehensive classification of test methods for the diagnosis of concrete structures. The main focus is on the ranges of suitability of the particular methods and techniques for assessing the durability of structures, depending on the principal degradation mechanisms and their effects on this durability. The survey covers non-destructive testing (NDT) methods, which do not in any way breach the integrity of the tested structures, and semi-destructive testing (SDT) methods requiring material samples to be taken or any other minor breach of structural integrity. An original taxonomy of physical, chemical and biological diagnostic methods, useful in assessment of concrete structures durability, is proposed. Equipment specific for selected advanced testing methods is presented as well as exemplary test results.

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