The operation of the electric motors, which are in poor health, leads to the direct financial losses, connected with an unpredictable failure of the equipment and, as a result, the violation of flow, and also the considerable cost of electricity, due to the high power consumption.
The diagnostics of the rotary equipment is usually made by the vibration parameter. However, the diagnostics of the equipment by the power consumption parameter has a great potential, since that allows to increase the depth of the diagnostics of the so-called electrical defects, i.e. defects and failures, connected with the electromagnetic forces disbalance. For instance, if the resistance to shaft movement occurs, so it would be reflected in the change of the respective current signal, and in the increasing of power consumption.
The physics principle in the basis of diagnostic complex operation is that any perturbations in the operation of the electric or mechanic part of an electric motor and equipment, connected with it, lead to the changes of the magnetic flux in the gap of the electric machine and, as a result, to the consumption current modulation.
Tkachenko A.A., Naumenko A.P. Research on the dependence of the parameters of the electric motor current consumption on its health // Science, education, business (“Nauka, obrazovanie, biznes”). - 2011. - pp. 217-219
Piston compressors are the indispensable equipment of oil-refining enterprises, the failure of which may lead to a significant decrease of production, and costly repairs, increasing the danger to life and health of workers.
One of the problems, arising from the operation of piston compressors and requiring an immediate detection, is a hydraulic impact. The hydraulic shock is a phenomenon, which is accompanied by an abrupt pressure increase in the decreasing space. The hydraulic impacts can cause the destructions of cylinder-piston group details and emergency situation occurrence.
The implementation of the automatic vibroacoustic condition monitoring and diagnostics of piston compressors COMPACS® allows to successfully prevent downtimes and accidents caused by hydraulic impacts. Diagnostics and monitoring are based on the control of the level of vibroacoustic sensor signal, axially proceeding from the cylinder cover at the moment of approach of the piston to the top dead center and the level of condensate in the separator. However, the diagnosis reliability increasing will always be an urgent task.
Sidorenko I.S., Naumenko A.P. Assessment of the possibility of using the characteristic function for hydraulic impacts diagnostics // Science, education, business (“Nauka, obrazovanie, biznes”). - 2011. - pp. 215-217
The standard reveals the requirements of safe operation of piston compressors, methods, volumes and time of revision of their details and assemblies, criteria of penalization due to wear, defects, vibration condition, operation life end, shows the data on quality assessment of the repair conducted and technical documentation created.
The standard is made for the specialists in operation, revision, repair and technical diagnostics of piston compressors. The standard is developed in replacement for "The main specifications of piston compressors repair", 1985.
The standard has been developed by DYNAMICS SPC: V.N. Kostyukov, A.P. Naumenko; "VNIKTIneftekhimoborudovaniye", JSC.
Piston compressors of the oil processing, petrochemical and chemical companies. Operation, technical supervision, audit, rejection and repair (STO 03-001-12) // Volgograd, 2013. – 242 p. ISBN 978-5-906081-72-8
Actual situation, when the rolling stock is maintained for appropriate condition due to the schedule-based preventive repair, suggests large resources costs on carrying out the planned repairs irrespectively of the actual condition of any MDRS-section unit. At the same time, the covert nature of defect nucleation and fault development leads to MDRS sections unscheduled decommissioning and additional costs.
An above-mentioned problems solving can be reached by means of an on-board condition monitoring system, making a real-time assessment of the each unit condition and giving information about the expediency of further operation. The efficiency of such a system consists in its continuous operation, i.e. the period of diagnosis, which is much smaller than fault development period in critical (emergency) condition, which gives an opportunity to carry out a condition-monitored operation of the machinery, avoiding the resource-intensive schedule-based preventive repair system.
The failures distribution analysis by the main groups of MDRS equipment shows a relatively high percentage of auxiliary machines faults in operation, it is about 10% and 20% of the detections during the repair and maintenance. The continuous condition monitoring of the auxiliary machines allows to minimize the costs for carrying out the schedule-based repair arrangement and to maximize its resource. In this case, the repair should be conducted only on those units, which are really in need of it in the required amount.
Tsurpal A.E. Failure analysis of supporting machines of motor driven rolling stock (MDRS) for its diagnostics // Science, education, business (“Nauka, obrazovanie, biznes”). - 2011. - pp.222-223
Statistical data about the traction motors failures, constituting more than 20% of the service failures total number, demonstrate the repair quality and motors testing at the repair enterprises. Thus, 65% of the motor failures occur for reasons of an electrical nature, such as: electrical breakdowns and turn-to-turn fault of armature winding, the main and additional poles, compensating windings. That testifies availability of factors, adversely affecting the dielectric resistance of the windings insulation. The suggestions for significant simplification of the traction electric motor testing process after repair, especially in the current repair № 3 process, are wrong.
Long-term experience in traction electric motors testing shows, that every month during the testing the 10-15 % of traction electric motors are identified with significant deviations in after-repair switching conditions at the Zheldorremmash plants.
On the assumption of the above-mentioned problems we suggest to tighten the control of testing and diagnostics of traction electric motors and fully automate the diagnostic complexes.
Melk V.V. Diagnostics of electric-driven rolling stock traction motors. Methods, types and main faults // Science, education, business (“Nauka, obrazovanie, biznes”). - 2011. - p. 184
Insufficient equipping of the most repair shops (of depots) with appropriate means of monitoring and diagnostics of electrical circuits doesn’t allow the personnel in charge of the safe electric trains operation to take reasonable steps for quality and timely elimination of defects, which don`t lead to equipment failure yet. Available instrumental measurement of individual parameters in majority of depots characterizes the condition of specific elements, but doesn’t provide objective information about the health of branches or sections of electric circuits, which includes these elements. This fact caused by distinction of internal interconnection between elements, branches and areas of electrical circuits from electrical circuits operation modes in general.
Thus, during the technical diagnostics development it is required to conduct the research with a view to determine these unit operation modes, in which the interconnection between the available measurement parameters and condition parameters of this unit is the strongest.
According to the task and the main diagnostic signs, selected for condition assessment and which are variables of their condition (current, voltage, voltage drop), the experimental unit for research of the functioning modes of train electric circuits is designed for their diagnostics.
The results and conclusions, obtained by computer experiments, are the basis of the method for power determination of each element (branch) of control circuit with the total current and method for diagnostics of electric circuits at EMU-trains, which have been successfully tested and confirmed high efficiency during the diagnostics of electric train different series real sections at the pilot unit, realized on the basis of computer monitoring hardware and software of the computer monitoring system for accidents prevention and condition control COMPACS®, implemented in a number of advanced EMU-train depots of "Russian Railways", JSC network.
Kazarin D.V. The experimental unit for the examination of the EMU-train electrical circuits functioning mode // Science, education, business (“Nauka, obrazovanie, biznes”). - 2011. - pp. 159-164
The experimental data for large samples can be represented in the form of a histogram, which is a graphic (empirical) estimate of the density probability. The number of the experimental data group intervals can be defined with the Williams formula. One can build the empirical distribution function based on the empirical density probability.
Weibull-Gnedenko distribution is used for the purpose of diagnostic characters statistical properties description, since such distribution is versatile enough and covers a wide range of the various processes probability characteristics changes cases by means of the parameters variation.
Along with the lognormal distribution this distribution satisfactorily describes details operating time based on fatigue damage, and mean time between failures of bearings. This distribution is used for an assessment of machines parts and components reliability.
Naumenko A.P. Diagnostic features statistical analysis methods // Science, education, business (“Nauka, obrazovanie, biznes”). - 2011. - pp.188-195
Light Gasoline Fraction Isomerization Unit Isomalk-2 commissioned at "Gazpromneft – Omsk Refinery" JSC on 29th of October, 2010, allowed to transfer whole work technique of the enterprise to a new level.
All rotating equipment of the unit: pumps, electric motors, air-cooling units (ACU) are under the permanent control of the computer monitoring system for accidents prevention and condition control - COMPACS®.
The system helps the personnel, managing "Izomalk-2" unit technological process, to obtain the current information on diagnosed equipment condition.
COMPACS® system operation on "Izomalk-2" unit rotating equipment in "Gazpromneft – Omsk Refinery", JSC allowed to implement the unit commissioning saving technologies and begin to carry out the diagnostics of equipment operation based on the actual condition.
The productions equipment with condition monitoring systems and the transition to condition-monitored equipment operation – that is a real way to ensure reliable, safe and stable operation of hazardous production, that , in turn, leads to an increase of production profitability. It is the way Omsk refinery plant operates already more than 20 years.
Kostyukov V.N., Kostyukov A.V., Tarasov E.V. COMPACS is on guard over new technology // Oil & Gas of Siberia, № 1(2). - 2011. - pp. 24-25
Automatic system for condition assessment of electric-driven rolling stock assemblies. Including wheel-motor units and wheel pairs.
The quality of production and repair of wheel-motor units and wheel pairs was always a priority, since the failures of such equipment are more hazardous over the consequences they can cause. The failures of rolling stock units of railway transport reduce the technical readiness coefficient, which leads to high operating costs in the sector.
The main reason of such situation is the high wear of a rolling stock and also lack of control of units` condition during their manufacture, repair and operation. It is possible to significantly reduce the number of unscheduled repairs and, as a result, the operating costs, by applying the quality diagnostic systems at plants and depots, control and monitoring systems of assemblies of rolling stock in the process of maintenance and current repair.
The system should allow to assess the quality of manufacture and/ or repair of wheel motor units and wheel reduction gear units to detect the hidden defects of bearings, gearbox gears, the lubrication quality and defects of assemblies’ balancing, alignment and fastening.
The various systems for diagnostics of the wheel-motor unit (WMU) of EMU-trains, which are notable not only for design features, but for a methodology, a diagnostic process, methods for defects determining, etc. are introduced and operated in Russian locomotive depots. The disadvantage of these systems is the low degree of the diagnostic process automation, that increases its duration, reduces the reliability and throughput of the systems. The automatic system for vibroacoustic diagnostics of WMU – COMPACS®-EXPRESS is described in the present article.
Kostyukov Al.V., Lagaev A.A., Zaitsev A.V. Assembling quality diagnostics // The World of Transport ("Mir Transporta"). - 2010. - № 3. - pp.70-74
The adequacy of the condition assessment of piston compressors of hazardous production, reliable and timely detection of faults and their causes, the risk rates of piston compressors safe operation are determined by the level of methodological basis development for the organization and operation algorithms of the soft-hardware of systems for piston compressors condition monitoring.
Nowadays, there are documents that define the basic requirements to the organization and the means of hazardous production facilities monitoring, but even for the experts in this field it is very difficult to orient oneself in the advertised capabilities of the systems. Thereby, there arises a need to range the methods and means of piston compressors condition monitoring and diagnostics.
The article dwells upon the development of condition and prospects of modern monitoring and diagnostic methods and means of piston compressors of hazardous process industries. The review of the condition control principles, implemented in nearly all the monitoring systems is made. The present article concentrates on technical means of monitoring systems.
The analysis of the methodology, techniques and principles of systems for real-time monitoring building is carried out. The article addresses the condition monitoring system of piston compressors in real-time COMPACS®.
Naumenko A.P. Modern methods and means of real-time condition monitoring of piston machines // Compressors and Pneumatics. - 2010. - №8. - pp. 27-34