Ensuring the safe operation of machine units such as pumps, compressors and other production equipment has always been one of the most relevant tasks in the industry. Failures of the mentioned machinery can often lead to malfunctions and accidents, causing losses and damaging the environment. For example, the analysis of statistics on oil refining and petrochemical industries shows that failures of machine units account for more than 70% of the total number of equipment failures in these industries.
The wide application of electric motors, including electric motors with a working voltage of 380 V, as part of machine units, necessitates the development and use of new methods for monitoring their technical condition, which allow detecting emerging defects at early stages and preventing their further development.
To assess the insulation condition of electrical machine windings, methods for controlling the parameters of partial discharges occurring in the insulation of windings are being increasingly used, which is caused by the improvement of technical and instrumental diagnostics, which allow to register and analyze such discharges.
Kostyukov V.N., Burda E.A. Study of the applicability of the partial discharge measurement method for diagnostics of insulation condition of stators of asynchronous electric motors with an operating voltage of 380 V // Science, Education, Business: Proceedings of Russian Radio-Day Scientific and Practical Conference for scientists, teachers, students, post-graduate students, industry and connection specialists. – Omsk, 2014. – p.228-233.
The main diagnostic task is to recognize condition of machines and units, classify them as faultless or faulty ones. The task is closely connected to false alarm or defect skipping risks.
When a method for axle equipment of wheel-motor units diagnostics is utilized there is always a chance of defect skipping or false alarm.
In rolling stock operation conditions, skipping a defect may lead to unit’s destruction, which cause not only an expensive unscheduled repair, train schedule failure, but also a technogenic hazard and transport accident.
False alarm may lead to additional repairs for units which does not require maintenance, and, consequently, make their condition even worse and decreasing rolling stock’s operating availability rates.
The paper is aimed at increasing diagnostic reliability with minimum expenses for testing procedures.
Kostyukov V.N., Zaytsev A.V., Teterin A.O. Increasing diagnostic reliability of axle equipment of wheel-motor units in electric trains // Science, Education, Business: Proceedings of Russian Radio-Day Scientific and Practical Conference for scientists, teachers, students, post-graduate students, industry and connection specialists. – Omsk, 2014. – p.183-190.
The paper is aimed at finding dependency between the RMS value of vibration parameters of rolling bearings in different conditions and the axial load.
he research is carried out by means of an experimental unit based on the COMPACS®-RPP system using drive 1602 which allows to set axial and radial load values and measure vibration radially.
The subject of research is an operable bearing, bearings with seeded defects of inner and outer race, and a bearing with rolling elements defect which occurred due to long-term service.
From the analysis of the obtained results one can make a conclusion on a rolling bearing condition having a considerable impact on RMS values’ dependency on an axial load.
The operable bearing and bearings with seeded defects of inner and outer race are lacking or have non-considerable amount of such dependency. That may testify that such seeded defects have no considerable impact on dependency between bearing vibration and an axial load.
Bearings with rolling element defects which occurred due to long-term service have RMS value considerably dependent on the applied axial load. The most sensitive to changes in axial load are RMS values of vibration displacement and vibration acceleration.
Kostyukov V.N., Boychenko S.N., Basakin V.V., Teterin A.O., Kudryavtseva I.S. Research on dependency of bearing vibration parameters on axial load // Science, Education, Business: Proceedings of Russian Radio-Day Scientific and Practical Conference for scientists, teachers, students, post-graduate students, industry and connection specialists. – Omsk, 2014. – p.123-127.
Rolling bearings are the most common and important elements applied in modern engineering. For rotary mechanical equipment – rolling bearings are node points limiting machinery operational resource in general.
The most effective method, which allows to detect both – nucleating and developed defects of rolling bearings, are vibration-acoustic method of NDT.
To make a valid assessment of rolling bearings condition – it is required to know how various factors are influencing vibration level.
The paper is aimed at studying a dependency between the RMS value of vibration parameters of rolling bearings in different conditions and the radial load.
Kostyukov V.N., Boychenko S.N., Basakin V.V., Teterin A.O., Kudryavtseva I.S. Research on dependency of bearing vibration parameters on radial load // Science, Education, Business: Proceedings of Russian Radio-Day Scientific and Practical Conference for scientists, teachers, students, post-graduate students, industry and connection specialists. – Omsk, 2014. – p.118-123.
Technology for real-time diagnostics and monitoring of piston machines is based on collection and processing of data which are to provide detection of defects and malfunctions of piston machines with specified detalization and accuracy, as well as their danger rates.
The technology implementation comprises usage of vibration-acoustic signal structure models in case of occurrence of defects and failures of assemblies and details of piston machines, combination of diagnostic features of failures and signal parameters in case of failure occurrence, ways of vibration-acoustic signal processing and evaluation system for the vibration-acoustic signal parameters.
One of the practical ways of the technology implementation and solutions of piston machines diagnostic and monitoring tasks is introduction of the given solutions which form a database connecting diagnostic features of failures and condition of piston machines’ details into functioning algorithms of the diagnostic and monitoring system COMPACS®.
The presented methodology of monitoring and diagnostics based on measuring the parameters of secondary processes (vibration-acoustic oscillations) allows to implement the algorithms of the real-time expert system for decision-making with automatic detection (diagnosing in time with diagnostic signals’ change) of more than 20 malfunctions of assemblies, such as piston compressors of hazardous production facilities, their danger rates and issuing prescriptions to the personnel for the required maintenance actions.
Naumenko A.P. Basic principles of technology for real-time diagnostics and monitoring of piston machines // XX Russian scientific conference on NDT and technical diagnostics: proceedings – Moscow: Spectr Editorial, 2014. – p.358-362.
The paper dwells upon the experience of operating condition monitoring systems for hazardous production facilities of power, mining, metallurgy and transport industries.
The paper shows the difference between the machinery parameter monitoring systems and condition monitoring systems. Parameter monitoring systems measure parameters of physical processes, however, without determining the causes of their change. Condition monitoring systems not only determine the change of physical parameters, but also the causes of their changes.
Those systems use algorithms of a real-time automatic decision-making expert system with an automatic machinery malfunction diagnosing, automatically show the personnel which actions should be made in order to eliminate the malfunctions.
Sometimes such systems in Russia are called “vibration monitoring systems”. The term “real-time” when referring to condition monitoring means that the speed of determining parameter measuring, condition evaluation, and depiction of the diagnostic results have to be adjusted to the speed of the machine’s degradation and exceed it by a few times in order to eliminate outliners and increase reliability of the diagnosis, along with creation of time reserve for making a management decision and carrying out all necessary actions.
Technical and economic efficiency indicators for the monitoring systems application are given in the paper.
Kostyukov V.N. Vibration monitoring of production and transport facilities // XX Russian scientific conference on NDT and technical diagnostics: proceedings – Moscow: Spectr Editorial, 2014. – p.357-358.
EMU-train depots widely use the COMPACS®-EXPRESS vibration acoustic diagnostics systems, designed for condition evaluation of WMU of motor-driven rolling stock during scheduled maintenance and repair works.
The diagnostics is aimed at increasing reliability and resource of technical systems. The main diagnostic task is to evaluate the condition of units and assemblies and classify it as good or faulty. That is closely connected with the risk of false alarm or defect skipping. The present work is devoted to reliability increase of rotary units’ condition diagnostics with simultaneous decrease of complexity of its usage.
An analysis of geometrical parameters of a bearing assembly resulted in dependency of vibration level from rotation frequency and defect’s size. According to the dependency, the vibration signal amplitude rate is proportional to the bearing rotation frequency and the defect’s size. Using the COMPACS®-EXPRESS systems the dependency proved valid. A diagnostic error connected with false alarm or defect skipping probability can be eliminated by using an ambiguity area limited by the highest and the lowest critical values.
The paper considers the developed approach to reduce the diagnostic error by using an ambiguity area and conducting an additional independent testing. Thus, using an ambiguity area in condition evaluation together with two independent tests, increasing complexity of its usage not more than by 2, substantially increases the reliability of rotary units condition diagnostics.
Kostyukov Al.V., Kazarin D.V., Zaytsev A.V. Reliability increase of rotary units’ vibration analysis // XX Russian scientific conference on NDT and technical diagnostics: proceedings – Moscow: Spectr Editorial, 2014. – p.355-357.
In terms of an operational process of rail-tracked rolling stock, the most important assemblies, liable to sudden failures, are limiting the rolling stock in general. Such assemblies include ones of electric and mechanical equipment which failures cannot be eliminated during operation.
The most efficient methods of detecting failures of rotary mechanical equipment is heating and vibration-acoustics, however, heating method allows barely state the fact of beginning of an assembly’s destruction, or find defects on a late stage of their development, as long as the vibration-acoustic method of NDT allows to detect both nucleating and developed defects.
Big amount of interferences and high noise level accompanying interaction of a wheel and a rail track has formed a common opinion on provision objective vibration acoustic condition diagnostics of rolling stock’s rotary machinery condition in operation being hard or, sometimes, impossible to achieve.
The research is aimed at providing the most informative, in terms of vibration-acoustic diagnostics, frequency range of a vibration signal, in order to develop an expert system and provide condition monitoring of a rail-tracked rolling stock.
Kostyukov Al.V., Tsurpal A.E., Basakin V.V. Research on vibration activity of assemblies in rail-tracked rolling stock’s mechanical parts // XX Russian scientific conference on NDT and technical diagnostics: proceedings – Moscow: Spectr Editorial, 2014. – p.353-355.
Today, the most common method to estimate centrifugal pump unit condition is vibration analysis which analyze vibration signals on the unit’s surface. In that case spectral analysis of signals is used, in which harmonic components of the spectrum are placed in correspondence with particular defects. However, usage of spectrum analysis requires precise information on the type and construction of the unit, its operation practice which might be imprecise or even absent. That might lead to condition estimation errors. Thus, a task of investigating new diagnostic methods using algorithms invariant to type and construction of the unit is urgent.
The paper considers using in diagnostics of centrifugal pump unit one of non-linear dynamic methods - fractal dimension, in which Hurst exponent of fractal dimension is used as a diagnostic feature. The main advantage of the feature is invariance to the level of analyzed signal, and, consequently, independency of power and dimension characteristics of the unit.
The paper reveals the results of researches on using the Hurst exponent of fractal dimension for determining unit’s cavitation carries out by means of the COMPACS®-RPG bench system for pump units testing. It is shown that the exponent’s response is accurate, and, in some cases, even more accurate than the main cavitation spectral feature – level of blade harmonics.
Thus, usage of the Hurst exponent of fractal dimension allows to improve reliability of output from an expert system for pump units condition diagnostic.
Kostyukov V.N., Boychenko S.N., Pavlenkov D.V. Usage of fractal dimension coefficient for vibration analysis of centrifugal pump units’ condition // XX Russian scientific conference on NDT and technical diagnostics: proceedings – Moscow: Spectr Editorial, 2014. – p.352-353.
Non-destructive testing and technical diagnostics of columns, reactors and tanks of refinery and petrochemical productions during operation on production conditions is an urgent task, which solution provides reliability and safety of explosive and flammable productions.
The computer monitoring and automatic diagnostics systems COMPACS® apply almost all methods of non-destructive testing: vibration, acoustic emission, heat, electric, eddy-current, acoustic, optical.
The principles of the system’s structure allow to provide flexibility and multipurposeness of the applied NDT methods. In that case the data are collected by various-type sensors, and an automatic expert system analyzes the facility’s condition.
Today, DYNAMICS SPC in collaboration with «FORC — Photonics» has solved the task on control provision by applying a fiber-optic technology for non-destructive testing purposes and technical diagnostics of columns and tanks at refinery and petrochemical production facilities in operation.
The paper considers application of fiber-optic technology in the COMPACS® systems in order to provide NDT and technical diagnostics of columns and tanks at refinery and petrochemical production facilities in operation.
Boychenko S.N., Tarasov E.V., Zarenbin A.V., Simonov M.A. Fiber-optic systems for temperature and strains monitoring // XX Russian scientific conference on NDT and technical diagnostics: proceedings – Moscow: Spectr Editorial, 2014. – p.247-248.