Diagnostics of the rolling stock wheel-motor units is an urgent matter of today. Bearing assemblies of wheel-sets and wheel-motor units (WMUs) undergo enormous impact forces and their technical condition largely influences a train performance safety.
It is customary to use 6 vibration sensors which are mounted on the general bearing assemblies (axle bearings, reducer, traction motor). Nevertheless there is an opinion that such a number of sensors is abundant and only increases diagnostic operations time.
In order to determine capability of vibration sensors number reduction while diagnosing of an electric train wheel-motor units, studies on the mutual impact between different subjects diagnostic features have been carried out.
Zaycev А.V., Lagaev А.А., Kostyukov V.N. Capability determination of vibration sensors number reduction while diagnosing of an electric train wheel-motor units // Nauka, obrazovanie, biznes (Science, education, business). - 2009. - pp. 154-157
Operating safety level of units with piston compressors is determined by reliability of their technical condition monitoring, timeliness and accuracy of malfunctions and their causes detection. Nowadays there are numerous technical tools designed for piston compressors monitoring and diagnostics, which are developed and manufactured in different countries by various companies. However, it remains a pending issue if the measurements are adequate to the actual technical condition of piston compressors and to the risk magnitude of their safe operation. Although there is a document that defines the general requirements for critical industrial facilities monitoring systems, nevertheless even experts find it rather difficult to sort out the advertised systems capabilities. In this connection there is an urgent necessity to systematize the condition diagnosing and monitoring methods and means for piston compressors.
Almost all monitoring and diagnostic systems are characterized by:
determination methodology for technical condition of piston compressors units and components is based on measurement of direct structural and technological parameters (relative displacement, pressure, temperature) and implements an online technology;
expert systems use the values of direct structural and technological parameters;
parameters of indirect processes (vibroacoustic oscillations) are used to assess these parameters values without a diagnosis-making and detection of malfunctions and defects causes.
In the equipment vibration analysis system COMPACS® the methodology for real-time monitoring and diagnostics is based not only on the measurement of direct structural and technological parameters, but on the use of vibroacoustic oscillation parameters as well, there have been implemented algorithms of the expert decision support system with an autodetection (in the rate of diagnostic signals measurement) of more than 20 units malfunctions and defects and the degree of their danger.
Naumenko A.P. Analysis of modern methods and means of piston compressors condition monitoring and diagnostics // Nauka, obrazovanie, biznes (Science, education, business). - 2009. - pp. 107-115
EMUs electrical circuits are divided into low-voltage control circuits, high voltage power and auxiliary circuits and in general constitute a complex, multi-element, multiply object with feedback loops and a large number of parameters, and its reliable operation has a significant influence upon the security and uninterrupted functioning of the railway carryover conveyor.
A repair system, designed to maintain an acceptable reliability level of rolling-stock and based on the scheduled preventive principle, has already exhausted its resource of cheap, skilled labor force and is not currently able to provide a high level of safety, keeping to schedule and improving the transportation process quality while reducing costs. Lack of modern and reliable devices for technical condition monitoring is the main reason of EMUs defects and failures. According to the statistical accounting of «Russian railways» JSC, about 60% of these defects and failures occur in electrical circuits.
Achievement of a high efficiency and reliability in the technical condition assessment of complex objects is possible on the basis of technical diagnostics devices, which development and implementation is preceded by phases of the object study and the diagnostic algorithms synthesis.
Electrical circuits can be represented as a single discrete logic device, whose input, internal and output signals have two stable states, respectively, and for their analysis it is advisable to use the mathematical apparatus of logical algebra.
Kazarin D.V. Synthesis of algorithms for diagnostics of electric circuits // Omsk Research Journal. - 2009. - pp. 133-135
Serviceability and performance capacity of repaired equipment is not objectively a guarantee of its correct operation as a part of this or that electric multiple unit system. Relationship between the elements, devices and units can be broken as a result of installation defects, damage can appear while transportation, assembling and subsequent debugging. The defects appearance at this stage of the technological cycle leads not only to duration increase of EMU putting into operation (debugging period), but, in the case of a defect omission, to spoilage and failures on the line.
Improving the quality of the motor driven rolling stock with a simultaneous reducing of debugging duration and complexity is possible on the basis of automated systems for comprehensive diagnostics of repair and assembling quality of the most complex and critical EMUs systems that provide a reliable quantitative and qualitative assessment of their technical condition, in accordance with the guidelines requirements.
The article presents some results concerning development and application of systems for comprehensive diagnostics of EMUs repair and assembling quality. EMUs are widely used at enterprises of «Russian Railways» JSC and at factories which are prospective for the railway industry being a means of improving reliability, maximizing EMUs exploitation with a simultaneous reducing of costs for repairs and speedy reconstruction of repair system on safe resource-saving basis.
Kostyukov V.N., Kostyukov Al.V., Kazarin D.V. Quality diagnostics of electric circuits assembling // Assembling in mechanical engineering, instrument making. - 2009. - № 12. - pp. 25-34
Design life of rolling bearings is determined by bearing capacity rating, equivalent load and bearing type (ball or roller). The equivalent load is determined by two factors: static and dynamic.
If the static load is determined by the machine operation mode and can vary within wide limits, the dynamic load is determined by the bearing state - all the roughness and defects in rolling elements and surfaces lead to an increase in dynamic forces affecting the bearing, and as a result, reduce its life. Besides, this decrease in life can be rather significant. Thus, for bearings with spoilage in production, when static and dynamic forces are comparable, the design life drops to 8 times for ball bearings and 10 times for roller ones. This explains the necessity for carrying out rolling bearings input vibration analysis before they are installed on the repaired or re-manufactured machines.
The article shows a dependence diagram of the bearing velocity overall level from the magnitude of the applied radial static load. It has been concluded that when measuring the bearing vibration parameters, we can judge about the magnitude of dynamic forces affecting the bearing, and thus we can more accurately evaluate its potential life.
Solution to the problem of purchased bearings 100% acceptance testing is the application of vibration analysis methods, where through the analysis of vibration signal one can quickly give an opinion on the bearing state without disassembling and micromeasuring. To solve this problem the benchtop system COMPACS®-RPP has been developed.
Kostyukov V.N., Boychenko S.N., Kostyukov A.V., Molteninov A.V., Buluchevsky Yu.V., Karpov S.Yu.,Dvukhzhilov D.V. , Shchelkanov A.V. Benchtop system for rolling bearings acceptance vibration analysis // Assembling in mechanical engineering, instrument making. - 2009. - № 4. - pp. 38-42
There is quite a large scope of the piston machines (PM), where the safety of their operation is paramount and decisive factor. These are PM of petrochemical complex (PCC) potentially hazardous facilities.
Sudden and emergency PCC equipment breakdown threatens not only the appearance of significant economic losses due to downtimes and working capacity restoration, but also environmental and man-made accidents and disasters. In this regard, it is very important to obtain not only reliable, but early diagnosis as well, which can provide trouble-free operation with maximum resource use of the replaceable units and parts.
This can be achieved only by providing a diagnosis-making at a time-interval, shorter than the malfunction development. For the PCC equipment this period can lie in the range from several minutes to hours, days, weeks, months.
The monitoring system of technical equipment COMPACS® allows to control purposefully and reliably the reciprocating compressors condition.
The article deals with methodological principles of operation and repair of reciprocating machines, compressors, in particular the hazardous continuous facilities compressors, according to the actual technical condition using the real-time technical condition monitoring systems. Examples of maintenance and repair on the monitoring system COMPACS® indications.
Kostyukov V.N., Naumenko A.P. Solutions to the problems of piston machines safe operation // Assembling in mechanical engineering, instrument making. - 2009. - №3. - p. 27-36
In the course of long-term theoretical and experimental researches the condition monitoring system for the refinery machine and column-storage equipment, which implements the concept of the real-time equipment operation on its technical condition, has been developed. High-precise diagnostics, built-in expert system for recognition of the defects main classes ensured the effective monitoring and the equipment technical condition forecast with an automatic issuance of regulations on equipment maintenance and their execution control. Refineries equipping with such monitoring systems increases safety and operational efficiency, as convincingly shown by the results of its maintenance: a significant reduction of sudden failures, a fourfold decrease of repairs, and the total savings from the implementation of the monitoring system are more than $6 million per year along with 1,5 months payback period.
The article shows a cause-and-effect relation between the situational costs increase, depending on the observability of the equipment condition, and the personnel actions. The analysis of the typical refinery equipment condition and its repair is shown. The concept of the equipment condition monitoring is revealed. The application of the comprehensive monitoring system COMPACS® is described to ensure the safe equipment operation on hazardous industrial facilities by real-time receiving the operational information about past, current and projected technical condition of equipment. The SM™-technology use in refineries production management has been presented.
Kostyukov V.N., Kostyukov A.V. Improving the refineries operational efficiency based on equipment condition monitoring // Oil & gas Journal. - 2009. - p. 57-64
Search and application for an estimation of a technical condition of machines of orthogonal diagnostic attributes represents rather actual problem as essentially increases reliability of diagnostics. Experience shows, that development of various malfunctions of rotor machines leads to that parameters vibroacceleration, vibrovelocity and vibrodisplacement react to these malfunctions on a miscellaneous. In a practice of vibration analysis and vibrocontrol the signals of vibroacceleration and vibrodisplacement often do not use, including their closely connected with a signal vibrovelocity, that these parameters are connected among themselves by differential-integrated ratio. These cases specify significant narrowing of a range of diagnosed malfunctions at use only one of these parameters.
By analytical researches, by numerical computer modelling and by means of natural experiments it is shown, that at diagnosing such malfunctions as defects of rolling and slidings bearings and, impellers of pumps, tooth gearings, infringement of centering of machines and fastening of units of machines to the bases, among themselves and to other attached designs, vibroacceleration, vibrovelocity and vibrodisplacement it is possible to consider parameters practically orthogonal. Thus, sharing for diagnostics of all three, parameters allows to observe in a spectrum of fluctuation of all frequencies raised in the mechanism.
Kostyukov A.V. Orthogonality of vibroacceleration, vibrovelocity and vibrodisplacement signals in vibration analysis tasks // Proceedingds of the 5th International Conference on Condition Monitoring & Machinery Failure Prevention Technologies. - 2008. - p. 794-80
Operation of the complex manufactures containing hundreds and thousand of units machine and the process equipment, is impossible without representation of the information on its technical condition to administration. Repair and modernization of the equipment, reconstruction of sites, shops and manufactures demand acceptance of the proved decisions which should base on a trustworthy information about the reasons of insufficient productivity, frequent repairs, idle times, industrial malfunctions and emergencies.
Reliability of the information is essentially determined by its objectivity, that is independence, of will, desires and reasons of the concrete people who are responsible for operation, repair, modernization of the equipment and reconstruction of manufacture. Only on the basis of the appropriate quality information, (authentic, received in due time and in necessary amount) it is possible to make the correct decisions determining success and profitableness of the enterprises.
KostyukovV.N. Condition monitoring of the equipment in real-time-technology of safe-save maintenance of the XXI century // Proceedingds of the 5th International Conference on Condition Monitoring & Machinery Failure Prevention Technologiess. - 2008. - p. 785-793
The offered classification of monitoring systems meets requirements of modern manufactures and is based on long-term experience of creation and introduction of systems of monitoring of a technical condition machine and the process equipment in real time of dangerous manufactures chemical, petrochemical, oil-extracting, refinery, mountain and an iron and steel industry, a railway transportation, a municipal services.
Boychenko S.N. Classification of the state monitoring systems // Proceedingds of the 5th International Conference on Condition Monitoring & Machinery Failure Prevention Technologiess. - 2008. - p. 178-184