Wyniki wyszukiwania - Biblioteka Nauki

1

The diagnosis of onboard generators (alternators)

100%

Gębura A. , Radoń T.

Polish Maritime Research

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2009

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tom nr 3

36-40

EN

In the paper selected problems related to diagnostics of onboard generators and alternators fitted with control systems are discussed. Problems refer to commutator generators and synchronous single- and threephase alternators. Special attention is paid to commutation effects. Results of incorrectness and possibility to detect them are discussed. There are also discussed effects associated with changes in a character of pulsation, which occur during shortings or insulation clearances in rotor or stator wiring. Possibility of diagnosis of generator’s or alternator’s parts by means of analysis of pulsation component parameters is indicated. In the case of alternators a number of diagnostic methods based on observation of changes in shape of voltage or frequency modulation, is discussed. This allows to detect many mechanical or electrical faults of generators, alternators or their control systems.

2

Analiza stopnia degradacji oleju smarującego w silnikach spalinowych

80%

Gomółka L. , Augustynowicz A. , Maciąg A.

Silniki Spalinowe

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2011

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tom R. 50, nr 3

PL

W opracowaniu przedstawiono analizę opartą na porównaniu poszczególnych właściwości fizyko-chemicznych oleju silnikowego podczas eksploatacji, służącą do oceny jego stanu. Pomimo, że producent określa czasookres użytkowania oleju silnikowego, nie jest to efektywny wskaźnik wymiany oleju silnikowego. Przeprowadzone w ramach pracy badania wykazały, że monitorowanie zmian stałej dielektrycznej oleju silnikowego może być pomocne do określenia jego stanu, ponieważ zmiany wartości zaproponowanego parametru diagnostycznego, jakim jest rozkład widma podczerwonego, są powiązane z właściwościami oleju silnikowego.

EN

In the study the diagnostic method based on the technique of high voltages is presented whose purpose is to serve for the evaluation of the state of the engine oil. Data describing the manufacturers' time exchange of the exploitation of the engine oil aren't an effective way of controlling the exchange of the engine oil. On the basis of conducted examinations it is demonstrated that monitoring the dielectric constant of the engine oil could be of help for determining its state, since changes of values of the suggested diagnostic parameter are connected with properties of engine oil.

3

Using of technical diagnostics for an analysis of failure causes and consequences of a selected vehicle

80%

Galliková J. , Ruman F.

Logistyka

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2015

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tom nr 4

3296--3301, CD2

EN

Technical diagnostics is one of the major forms of the overall care of vehicles. It is through improving and streamlining maintenance that is non-invasive methods to execute the control of the functional situation and technical condition of the vehicles, their aggregates and construction units. This can significantly reduce maintenance costs and improve control of performed maintenance. The aim of introducing the diagnosis and the automatic diagnosis of vehicles is increasing the actual availability of vehicles, increase their reliability and operational safety, improve the quality and efficiency of maintenance and repair industry through control and decision-making activities. The work is based on an analysis of diagnostic methods, computer-aided FMEA analysis is performed on selected vehicle and the consequences of failure modes are determined. The results obtained from FMEA is done in the program APIS PRO 6.0 for the causes and consequences of failures. Critical parts are determined and measures to mitigate the effects of failures are proposed.

4

Evaluation of degradation of bricks using FRF

80%

Żółtowski M. , Napieraj K.

Budownictwo i Architektura

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2017

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tom Vol. 16, nr 3

25--36

EN

The knowledge of the dynamic state and structure of system allows to describe its behavior, and allows a model of the system behavior in the function of dynamic evolution time, based on the model of the technical state symptoms growth. Most often, there are no known equations describing behaviors of the system in the function of dynamic evolution time, which accounts for the need to apply new tools to examine the dynamic state. In this article authors shows chosen problems of technical state diagnosis with the use of identification and technical diagnostics methods such as experimental modal analysis. Relations between methods of dynamic state evaluation and methods of technical state evaluation were indicated. Example modal analysis results illustrate the complexity of projecting dynamic state researches into diagnostic researches of state evaluation.

5

Capabilities of estimation of rotor dynamic state on the ground of trajectories of bearing journals

80%

Rybczyński J.

Transactions of the Institute of Fluid-Flow Machinery

|

2005

|

tom nr 116

43-56

EN

In the paper presented are capabilities of advanced rotary machinery diagnostics based on the analysis of trajectories of slider bearing journals. Outlined and characterized have been the categories of rotary machine malfunctioning, which can be detected and discriminated on the basis of images of the journal center trajectory. Discussed have been these elements of trajectories, which bear information about the dynamic state of the machine and which can contribute to differentiation of the machine defects. Principles of diagnostics of the machine state have been analysed from the point of view of relations between the trajectory feature and the rotor dynamic state. Presented problems are based on author's own expertise and have been illustrated by sample images stemming from author's own experimental investigations as well as numerical simulations conducted using own computer codes. The material contained in the paper can be helpful in practical diagnostic applications.

6

Problems of modelling toxic compounds emitted by a marine internal combustion engine in unsteady states

80%

Rudnicki J. , Zadrąg R.

Polish Maritime Research

|

2014

|

tom nr 4

57--65

EN

Contemporary engine tests are performed based on the theory of experiment. The available versions of programmes used for analysing experimental data make frequent use of the multiple regression model, which enables examining effects and interactions between input model parameters and a single output variable. The use of multi-equation models provides more freedom in analysing the measured results, as those models enable simultaneous analysis of effects and interactions between many output variables. They can also be used as a tool in preparing experimental material for other advanced diagnostic tools, such as the models making use of neural networks which, when properly prepared, enable also analysing measurement results recorded during dynamic processes. The article presents advantages of the use of the abovementioned analytical tools and a sample application of the neural model developed based on the results of examination carried out on the engine research rig.

7

Niekonwencjonalne metody badań diagnostycznych drutów lin stalowych

80%

Hankus J. , Hankus Ł.

Hutnik, Wiadomości Hutnicze

|

2005

|

tom Vol. 72, nr 2

56-58

PL

Diagnostyka techniczna pracujących lin stalowych obejmuje szeroki zakres badań prowadzonych zarówno w warunkach ruchowych, jak i laboratoryjnych [5, 6]. Badania takie między innymi od przeszło 50 lat prowadzi Laboratorium Lin i Urządzeń Szybowych Głównego Instytutu Górnictwa w Katowicach. W pracy podjęto próbę wykorzystania w diagnostyce technicznej drutów lin stalowych dodatkowych metod. Przykład pierwszy dotyczy znanych już od kilkudziesięciu wieków badań radiestezyjnych, których podstawę stanowią prawa biomagnetyzmu. Przykład drugi to nowa metoda wykorzystująca magnetyczną pamięć metalu MPM i naturalne namagnesowanie w magnetycznym polu Ziemi.

EN

The technical diagnostics of operating steel wire ropes includes a wide range of tests conducted both infield and in laboratory conditions [5, 6]. Such tests have been, among the others, conducted for 50 years by the Central Mining Institutes Laboratory for Ropes and Shaft Equipment Testing in Katowice, Poland. The paper undertages a trial to evaluate the possibilities of using additional methods in the technical diagnostics of steel wire ropes.The first example relates to dowsing investigation, already known for tens of centuries, the basis of which is given by the laws of bio-magnetism. The second example is a new method, which utilises the magnetic memory of metal (MMM), and natural magnetisation in the magnetic field of the Earth.

8

The possibilities of diagnosing common-rail injection systems of marine diesel engines

80%

Beiger A.

Journal of Polish CIMAC

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2011

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tom Vol. 6, no 2

15-22

EN

This article presents the application of acoustic stress wave emission for diagnosing Common-Rail injection systems of engines. Failures typical to such systems, as well as problems connected with faulty operation of injectors, have been presented. One of the methods of acoustic emission signal analysis has been discussed. It enables a non-invasive way of diagnosing the injection system of an engine with self-ignition and the Common-Rail system.

9

Endoscopic image processing and analysis of pistions' service failures of marine diesel engines

80%

Korczewski Z.

Journal of Polish CIMAC

|

2011

|

tom Vol. 6, no 2

127-136

EN

The paper deals with diagnostic issues concerning endoscopic examinations of working spaces within marine diesel engines. In the beginning, endoscopy apparatus being on laboratory equipment of the Department of Ship Power Plants of Gdansk University of Technology has been characterized. The endoscopy considerations have been focused on theoretical bases of a digital image processing and especially - on the “Shadow” measurement method. Second part of the paper is devoted to operation damages of medium- and high speed engines that have been physically analyzed in many aspects of origin as well as places and character of their occurrence. There have been also considered possibilities of direct and indirect identification of the well known and recognizable operational unserviceable states of the elements of a piston’s constructional system by means of endoscopic methods. The results of the author’s own research as well as the accessible results of diagnostic research of the self ignition engines applied in automotive and railway transport have explained and proved the most probable reasons for the piston failures’ occurrence.

10

Niezawodność dostaw energii elektrycznej jako miara efektywności diagnostyki technicznej w sieciach elektroenergetycznych

80%

Dąbrowska-Kauf G.

Diagnostyka

|

2005

|

tom Vol. 33

203--208

PL

Sieć elektroenergetyczna składa się z wielu urządzeń i jest narażona na działanie różnorodnych czynników, które powodują zakłócenia w jej pracy. Skutkiem tego mogą być przerwy w zasilaniu lub pogorszenie jakości energii elektrycznej. Długość tych przerw zależy w istotny sposób od prawidłowej diagnostyki: elementów sieci i procesów przesyłu i dystrybucji energii elektrycznej. Efektywność diagnostyki technicznej w sieciach elektroenergetycznej wpływa bezpośrednio na niezawodności dostaw energii elektrycznej. W artykule omówiono metodę pozwalającą mierzyć efektywność diagnostyki technicznej w oparciu o wykorzystanie wyznaczanych współczynników niezawodności poszczególnych elementów sieci elektroenergetycznej.

EN

Distributed power network consists of many devices and therefore it is exsposed to the activity of various factors which result in interferences during their work. The causes of this include pauses in power supply and deterioration of the eneregy's quality. The length of the pauses depends in an essential way on undertaking correct diagnostical decisions in the area of the power network's elements and the electricity distribution. Efficiency of technical diagnostics in power network depends directly on reliablity rate of electricity supply. In the article, the method, that allows measuring the efficiency of technical diagnostics, based on a usage of assigned coefficients of reliability rates of particular elements in the power network, is presented.

11

The use of the vibration method in testing steel load-bearing cables for the purpose of developing a method of measuring their state of tension

80%

Bartmański C. , Bramorska A.

Measurement Automation Monitoring

|

2017

|

tom Vol. 63, No. 8

258--262

EN

In technical diagnostics of load-bearing tendons of bridge and building structures, vibration methods are popular due to simplicity, speed of results and low costs of their application. The aim of the research was to develop a method for measuring the load-bearing cables stress. The article presents the results of tests on the cable testing stand, which enable identification of the parameters of the cable dynamic model. In the research, a technique was applied consisting in impulse stimulation to vibrations of the tense steel cable and analysis of signals, which are a response of the cable to this excitation. Using the modal analysis method, the dependence of the frequency of various forms of the cable natural vibrations on the cable tensioning force was determined. Three types of cables were tested. The bending rigidity of the cable was determined. Using the modal analysis method as a reference method, the usefulness of a simpler method of evaluating cable natural frequency, was examined.

12

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines. Part III. Diagnostic and operating tolerances

80%

Korczewski Z.

Polish Maritime Research

|

2011

|

tom nr 4

49-53

EN

The third part of the article presents a method for detecting failures of the automatic engine control system with the aid of an exhaust gas temperature setter, specially designed and machined for this purpose. It also presents a procedure of identifying the operating tolerances and determining the diagnostic tolerances for the exhaust gas temperature recorded in the naval turbine engine during the start-up and acceleration processes. The diagnostic tolerances were determined using the statistic inference, based on the hypothesis about the normal distribution of the starting exhaust gas temperature dispersion at the initial time of engine operation. The above hypothesis was verified using the non-parametric statistic test ÷2 for examining the consistency of the empirical distribution with the assumed normal distribution. As a result of the examination, satisfactory convergence of the compared distributions was obtained which made the basis for assuming the three-sigma limits of the diagnostic tolerance for the analysed engine control parameter.

13

Keeping mining machinery in operation based on energy factors

80%

Korbiel T. , Czerwiński S.

Mining Machines

|

2022

|

tom vol. 40, iss. 3

123--128

EN

Mining machinery maintenance strategy based on the current dynamic condition of the equipment not only improves reliability, reduces repair and renovation costs, but also affects electricity costs. Due to the use of modern monitoring and diagnostic systems, as well as advanced control and supervision methods, it is possible to improve the efficiency of devices and thus reduce energy costs. Due to the high power of the devices, even a slight decrease in efficiency translates into significant financial resources. Taking into account the prices of electricity as well as ecological aspects, investments in modern solutions give specific financial and social savings.

14

Modelling in technical diagnostics

80%

Żółtowski B.

Journal of KONES

|

2010

|

tom Vol. 17, No. 3

541-546

EN

The knowledge of the dynamic stat and structure of the system allows desercribing its behaviour, and allows creating prognosis models of the system behaviour in the function of dynamic evolution time, based on the model of the technical state symptoms growth. Most often, however, there are no known equations describing behaviours of the system in the function of dynamic evolution time, which accounts for the need to apply new tools to examine the dynamic state. There is, therefore, the requirement to experimentally verify analytical technical models as the proper one is a model which is verified in practice. An experiment is, therefore, often only an inspiration for further researches leading to the optimization of the construction. In this work presented are chosen problems of machines technical state diagnosis with the use of identification and technical diagnostics methods. Relations between methods of dynamic state evaluation and methods of technical state evaluation were indicated. Example modal analysis results illustrate the complexity of projecting dynamic state researches into diagnostic researches of machine state evaluation.

15

Diagnosis modern systems of marine diesel engine

80%

Krakowski R.

Journal of KONES

|

2014

|

tom Vol. 21, No. 3

191--198

EN

In this paper, in terms of diagnostic tests, functional systems composed of a technical object that is marine diesel engine piston were presented. This decomposition enables the identification of diagnostic systems, where failures occur most frequently and those whose failure may cause serious This decomposition enables the identification of diagnostic systems, where failures occur most frequently and those whose failure may cause serious consequences further consequences. Marine diesel engine was divided into the following functional systems: piston-crank exchange of the working medium, fuel supply, lubrication, cooling, starting, starting and reversing. Operating practice shows that the most common marine engine failure include damage to the injection system, the injectors, injection pumps, fuel system, speed controllers, lubrication system, timing mechanism, as well as the cooling system malfunctions. In this paper, examples of currently used diagnostic systems were described. In addition, the unconventional methods of diagnosing piston engines were presented. These are new, increasingly completely without disassembly and without any interference in the process of the internal combustion engine technical condition testing methods. Measurement systems computerization causes they are used with the simultaneous use of artificial intelligence and especially expert systems. These include, inter alia, vibration analysis, marine engine exhaust gas analysis, acoustic emission, endoscopy and quick photography in research diagnostics. Then infirmities cooling system were presented. The problem of development of methods of diagnosis and diagnostic system for marine diesel engine cooling system was formulated. It has been found that the developed diagnostic system would be a good complement to the existing electronic surveillance systems of the marine engine technical state.

16

Diagnostics of vessel power plants

80%

Charchalis A.

Journal of KONES

|

2011

|

tom Vol. 18, No. 2

41-47

EN

In this paper, the problems of diagnostics of main propulsion marine engines are presented. Diesel or turbine engines are used for main propulsion of vessel power plants. Marine engine is a complex technical object. For the purpose of diagnostics it is convenient to divide the engine into several units - subsystems such as: piston -crank assembly; working medium exchange system, fuel supply system, lubricating system, cooling system, starting up -reversing system; combustion chamber. The organization of the marine engine diagnostic process can usually come down to two stages, general diagnostics and damage location. Most popular in marine engine diagnostics have been the periodic run analyzers, called pressure analyzers, electronic indicators or MIP (Mean Indicated Pressure) calculators. Marine turbine engine operation requires professional technical supervision. The basic diagnostic system of marine turbine engine is able to assess the current engine condition and give forecast concerning its future operation in a complex way with the use of computer technology. Working out operating decision was based on proper preparation of operational parameters which were processed in a computer according to defined algorithms. Diesel engine diagnostic systems of merchant vessel engines are discussed. Finally, description of diagnostic methods implemented in turbine and piston engines in Polish Navy ships are introduced.

17

Verification of diagnostic thresholds with elimination of ambient factors

80%

Lindstedt P. , Zboiński M. , Deliś M. , Borowczyk H.

Journal of KONBiN

|

2015

|

tom No. 1 (33)

61--80

EN

Measurements of signals received from ambient environment is a difficult task for technical diagnostics and becomes even infeasible in a series of cases. It is why the issues related to elimination of ambient factors from the identification process of diagnostic thresholds are truly justified. The method for elimination of environment impact is disclosed in this paper and consists in displacement of a specific set of measured diagnostic parameters (the initial set) in relation to the subsequent set of diagnostic parameters (the target set). Then the square of amplitude gain and the phase shift are calculated for these two mutually shifted data sets, which makes it possible to evaluate “cohesion” density of results obtained for diagnostic signals and thus their suitability for calculation of diagnostic thresholds. The method is characterized by the peculiarity that it takes account for ambient “environment” with no need to measure its parameters [6, 7, 8, 12, 13, 14].

PL

Trudnym do rozwiązania problemem diagnostyki technicznej jest pomiar sygnałów otoczenia. W wielu przypadkach pomiar ten jest niemożliwy. Stąd podjęcie problemu eliminacji otoczenia z procesu identyfikacji progów diagnostycznych jest zasadne. Przedstawiony sposób eliminacji otoczenia polegający na przesuwaniu danego zbioru pomiarów parametrów diagnostycznych (zbioru początkowego) względem kolejnego zbioru pomiarów diagnostycznych (zbioru następnego), a następnie wyznaczenie kwadratu wzmocnienia amplitudowego i przesunięcia fazowego dla tak przesuniętych zbiorów, pozwala ocenić „skupienie” pomiarów sygnałów diagnostycznych i stąd ich przydatność do obliczenia progów diagnostycznych. Metoda znamienna jest tą osobliwością, że uwzględnia ona „otoczenie” bez konieczności jego pomiaru [6, 7, 8, 12, 13, 14].

18

Reliability and its relation to regulation and diagnostics in the machinery exploitation systems

80%

Lindstedt P.

Journal of KONBiN

|

2006

|

tom No. 2

317--330

EN

The paper presents a cybernetic system that describes the exploitation of technical equipment. It is emphasized that basic parameters of the system include reliability, diagnostics and regulation, therefore mutual relationships between those three parameters are established and described. It is proved that the “map of defects” of the object (reliability) makes it possible to determine a set of diagnostic signals that represent the technical condition of the object and reflect possible alteration of the object status (diagnostics). Subsequently, detected alterations can serve as a background for necessary adjustment of technical equipment (regulation).

19

Procedure Of Constructing And Evaluating Linear Diagnostic Models Of Complex Objects

80%

Żółtowski B.

Journal of Polish CIMAC

|

2009

|

tom Vol. 4, no 2

349-354

20

Determining patterns of some defect-symptom type diagnostic relations for a turboset in steady-state operation and rundown conditions

80%

Rybczyński J.

Transactions of the Institute of Fluid-Flow Machinery

|

2007

|

tom nr 120

23-51

EN

The article presents results of the research oriented on determining a set of diagnostic relations referring to a special, but relatively common class of turboset defects, consisting in the misalignment of great turbine set bearings with respect to their designed base positions. The paper discusses a collection of types of the diagnostic relations obtained via simulation calculations of the dynamic state of the machine in steady-state operation and transient conditions. Numerical calculations were carried-out, with the aid of a package of MESWIR codes, on a model turbine set in which the bearings have been dislocated by the maximum permissible range. For this purpose the maximum permissible misalignments of all seven turbine set bearings were calculated. The research makes it possible to formulate a system of diagnostic relations connected with the bearing lateral dislocation defect, which can make the knowledge basis for a diagnostic system.