Photometric Method of Diagnosis of Bearing Units Operating with Hydrocarbon Mixtures

2018 ◽  
Vol 284 ◽  
pp. 1342-1348
Author(s):  
E.N. Gryadunova ◽  
R.N. Polyakov ◽  
N.V. Tokmakov

The article is devoted to the diagnosis of bearing units working with hydrocarbon mixtures. The diagnostic is based on the photometric method. This method allows you to determine the internal damage to the bearing unit at the stage of the appearance of the microcrack. The photometric method is based on changing the color of the indicator fabric. As the indicator substance, a bromine solution was used which had a dark brown color. If there is a leak, the hydrocarbon reacts with bromine molecules and a bright spot appears on the tape. Indicator fabric is applied to the bearing unit during assembling.The material of the article contains a model of the physicochemical process, which is the basis of the photometric method. Various stages of leakage of hydrocarbon mixtures through microcracks were studied. The results of the experimental studies are consistent with the theoretical propositions. The proposed diagnostic method can be used as a method for non-destructive testing of bearing units.

2013 ◽  
Vol 401-403 ◽  
pp. 978-981
Author(s):  
Xiao Wen Zeng ◽  
Yong Mei Zhang

The infrared thermal imagery technology receives more and more attention in the civil engineering because of its unique advantages. But there is still room for more in-depth theoretical and experimental studies in the aspect of its applicable scope, test method, the result and the precision analysis and so on. Through the research of the infrared thermogram of water-containing and insulation-free roof specimen and glass fiber insulation roofing specimen, this paper mainly analyzes the factors which influence detection of the roof leakage by using infrared thermal method and gives some suggestion for the application of infrared thermal imaging in the roof leak detection. Thus it provides the theory basis and the technical reference for the actual infrared non-destructive testing.


2021 ◽  
Vol 280 ◽  
pp. 07010
Author(s):  
Serhiі Mazurchuk ◽  
Nataliya Marchenko ◽  
Yuriy Tsapko ◽  
Olga Bondarenko ◽  
Nataliya Buyskikh ◽  
...  

The article presents the main results of experimental studies on the identification of the main grade defects of oak lumber by the thermal non-destructive testing method. Regressional dependences of wood defects temperature display from the main factors for the studied grade defects are proposed. Indicators of infrared radiation (temperature range) of the main visible oak grade defects obtained as a result of experimental studies are presented. A conceptual scheme for the line control methods of identification of the main grade defects in lumber are proposed.


2021 ◽  
Vol 6 ◽  
pp. 35-45
Author(s):  
С.В. Дубинский ◽  
Е.А. Казьмин ◽  
И.Е. Ковалев ◽  
А.Б. Корнилов ◽  
Г.А. Корнилов ◽  
...  

The method of vibrothermography may be considered as one of the promising thermal non-destructive testing techniques, which can be applied for the detection of internal damage in composite structures. The thermal excitation of the structure in case of vibrothermography is caused by the mechanical oscillations on the sonic or ultrasonic frequency, and the change in temperature field of the object is controlled by thermography methods. The present paper considers the method of vibration testing and presents the results of thermography studies focused on the behavior of composite structure with impact damage subjected to vibration loading.


Author(s):  
C. Li ◽  
J. Yang ◽  
X. Zhang ◽  
M. Fu

<p><strong>Abstract.</strong> With the increasing emphasis on the conservation of cultural relics, the renovation work of historic buildings has become more and more important. Basically, most of the ancient buildings in China are wooden structure. Wood is a flexible material which could resist deformation in the earthquake. The drawback, however, is that they are susceptible to temperature, humidity and other external influences (which will lead to rot, cracks, tilt, foundation settlement, etc.), and poses a hidden danger to entire architecture. Besides, after years of use, the decline in mechanical properties could affects their bearing capacity. Moreover, traditional renovation methods, determining renovation and demolition in the absence of accurate and effective detection and evaluation methods, like eyeballing, knocking, which are simple and depend largely on manual experience and lacks of accuracy, will cause the loss of historical information of ancient construction. Also, Traditional way of stylobate repairing can only be qualitative analysis which are visually or empirically, deciding partial repair or comprehensive replacement. Internal damage remains unclearly and inaccurately that often result in the loss of historical information and over-repair of heritage. Paper aims to interpret with two typical example in Mukden Palace, where located in the temperate sub-humid continental climate, with a huge temperature difference between day and night, one is the stone stylobate of Dazheng Hall, the palace used for holding ceremonies, the other is the wooden structure of Ancestral Temple. Both faced with varying degrees of damage, such as foundation broken, frieze panel inclined and pillar cracked. Non-destructive Testing (NDT) Technology using in those two projects includes 3D scanning, ground penetrating, concrete ultrasonic testing and mineral element analyzing that can collect data more comprehensive than just using traditional methods, especially for internal damage. Then generating the quantitative analysis of damage category. Furthermore, discussing cause of damage and moderately protection methods of the stone stylobate and the wooden structure on the basis of testing. As well as providing references of repairing project of traditional Chinese stony heritage.</p>


2018 ◽  
Vol 77 (3) ◽  
pp. 182-187 ◽  
Author(s):  
A. N. Kireev

When forecasting the technical state of the parts and units of railway rolling stock in operation, an important task is to determine the shape of the discontinuity in ultrasonic non-destructive testing in order to predict its behavior in further operation (this is especially important if the discontinuity in the results of such control is acceptable). Author proposed a solution for the improvement of the two-frequency defectometry method. A mathematical apparatus was developed and a method for determining the coefficient of the discontinuity shape was elaborate on its basis. The method makes it possible to determine the shape of both a point and an extended discontinuity. The software product NDTRT-07.03.01.18 was developed to automate calculations in determining the shape of discontinuity by a two-frequency method. The article gives a description of the experimental studies carried out to evaluate the reliability of the proposed method. This method can be used in determining the shape of the discontinuity in the details of the rolling stock, in which the defect can have a different shape, for example: cast wheel centers; various shaped castings used in the manufacture of rolling stock units (brackets for locomotive bogies, cast sidewalls for cars), as well as in parts manufactured by the method of plastic deformation, including wheel treads, axles, all-rolled wheels, rolled wheel centers, etc. In these details discontinuities are predominantly planar in nature, but voluminous discontinuities are also encountered - non-deformable nonmetallic inclusions, therefore the developed method can be applied to such objects of rolling stock railways.


2021 ◽  
Vol 6 ◽  
pp. 26-34
Author(s):  
Н.П. Алешин ◽  
Н.В. Крысько ◽  
С.В. Скрынников ◽  
А.Г. Кусый

The issues of detecting operational surface planar flaws by the ultrasonic non-destructive testing method with the use of Rayleigh surface waves generated by an electromagnetic-acoustic transducer are considered. The paper presents experimental studies of planar defects detection, simulated by an artificial reflector of the "notch" type with different width, depth and angle of inclination. The dependences of the signal amplitude on the listed parameters are constructed and their character was estimated. The optimal amplitude models for constructing the probability of detection curves (PoD) have been determined. A conclusion is made about the minimum dimensions of an operational planar flaw detected by the considering method with a probability of 90%, taking into account the confidence interval of 95%.


2011 ◽  
Vol 159 (1) ◽  
pp. 261-270
Author(s):  
Marek SZUDROWICZ ◽  
Waldemar ŚWIDERSKI

Composite armour is a preferred solution against military and paramilitary threats at present. Composite armour has to be resistant against impacts of fragments and bullets as well as mines and grenades. Except visible external damage of composite armour, its internal damage is equally essential. An IR thermography non-destructive testing method was used to identify delamination areas in composite armour. The results of these tests are presented in the paper. The authors also discuss the possibilities of composite armour repair methods.


Author(s):  
R. T. Martyniuk ◽  
O. T. Chernova ◽  
M. R. Shyan

The basic principle of diagnosing long-life metal structures, and pipe­lines in particular, is based on consistent and systematic measurements of certain design parameters, on detecting changes in these parameters during operation and comparing them with the original ones, and on predicting changes in these parameters. The application of technical diagnostics and non-destructive testing methods to determine the actual technical status is a regular technological operation and, as experience shows, an effective way of ensuring the tech­nical reliability and safe operation of pipelines and the gas transmission system as a whole. The methods of non-destructive testing, correlation analysis and mod­ern methods of statistical processing of experimental and reference data (artificial neural networks) were used to determine the actual state of oil and gas pipelines. Factor and regression analysis methods were used during theoretical studies. In the course of the experimental studies, the methods of experiment planning, probability theory were used.


Author(s):  
А.В. Илющенко ◽  
А.Н. Чубинский

В мировой практике для определения качества пиломатериалов широко используют неразрушающие методы контроля. Анализируются достоинства и недостатки наиболее распространенных методов. Делается вывод, что наиболее приемлем в условиях современного производства - фотометрический метод, поскольку обладает рядом преимуществ: удобен в использовании, легко интегрируем в технологический процесс, не требует больших инвестиций. Данный метод является наиболее эффективным в комбинации с силовой сортировкой на предприятиях, выпускающих пиломатериалы конструкционного назначения. Сортировка по предлагаемой схеме осуществляется в два этапа: на первом посредством фотометрии выявляются очевидно непригодные к большим нагрузкам пиломатериалы, второй этап позволяет повысить точность оценки свойств пиломатериалов для несущих конструкционных пиломатериалов. Отмечаются проблемы, которые могут возникнуть при внедрении такой схемы, и возможные пути их решения. Указывается на отсутствие достаточной информационной базы в электронном виде о влиянии пороков на прочность древесины, особенно при скоплении пороков одного типа или наложении разных типов в одной области пиломатериала. Приводятся ссылки на исследования, согласно которым нормы допуска основных пороков установлены без должного обоснования. Делается вывод о том, что сорт не дает достоверных сведений о прочности конструкционных материалов, в то время как для прочих пиломатериалов имеют значение предпочтения потребителей, визуальные характеристики продукции из пиломатериалов, например количество, размеры, качество и расположение пороков. Предлагается ввести границы применимости различных методов сортировки пиломатериалов (визуальная, силовая, компьютерная томография и др.). Приводятся группы признаков, необходимые для распознавания пороков: морфометрические, цветовые, текстурные. На примере двух распространенных видов пороков (сучков и трещин) демонстрируются возможности распознавания их системой «машинного зрения». В табличном виде представлен перечень части признаков, по которым велось распознавание. In world practice, to determine the quality of lumber is widely used non-destructive testing methods. The paper analyzes the advantages and disadvantages of the most common methods. It is concluded that the most appropriate in today's production is the photometric method, as it has several advantages: easy to use, easy to integrate in the process, does not require large investments. It is noted that this method is most effective in combination with the power sorting in enterprises producing timber for constructional purposes. Sorting by the proposed scheme is carried out in two stages: the first detected by photometry obviously unfit for heavy loads timber, the second stage can improve the accuracy of evaluation of the properties of sawn timber for structural constructions. There have been problems that may arise in the implementation of such a scheme and the possible solutions. It indicates a lack of adequate information base in electronic form on the influence of defects on the strength of the wood, especially in a cluster of defects of one type or the imposition of different types in one area of ​​the sawn timber. Provides links to research, according to which the rules of admission of the major vices installed without proper justification. The conclusion is that the variety does not provide reliable information about the structural strength of materials, while for other sawn timber are important consumer preferences, visual characteristics of the production of sawn timber, such as the number, size, quality and location of the defects. It is proposed to enter the limits of applicability of various lumber sorting methods (visual, power, computer tomography and others). Are given a group of features required for recognition of defects: morphometric, color, texture. Two common types of defects (knots and cracks) are demonstrated the possibility of recognition of their by system of «machine vision» for. The tabular form is submitted the list of the grounds on which recognition was shown.


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