scholarly journals ASSESSMENT CARTS STRENGTH INDICATORS WAGONS WITH EXPIRED SERVICE LIFE

Author(s):  
O. Fomin

Currently, a significant number of units of specialized cars of 1520 mm gauge in Ukraine has a service life that exceeds that assigned by the manufacturer. At the same time, many years of experience in diagnosing and analyzing the operation of carts of these cars by specialized organizations, shows that their technical condition after long operation shows that the specified service life specified in the technical conditions in most cases far from the limit. This is largely due to the significant margin of safety, which is laid down in the design, and the peculiarities of the operation of a particular type of car. The paper considers the issues of assessing the operation of such cars on the example of the carriage of the weighing car, bogie model 18-102, and the carriage of the passenger car model KVZ-TsNII used in the track economy for transportation of workers. The average daily mileage of such cars is 60-70 percent less than the average mileage that is laid down when calculating the service life assigned by the manufacturer. The evaluation and methods of determining the strength of the frames of carriages of special cars are performed. Conclusions are made based on the results of the analysis of the strength of the carriages of special cars.

Author(s):  
M. Radkevych ◽  
S. Sapronova ◽  
N. Braikovska ◽  
V. Tkachenko

Extension of the service life of a particular passenger railway car can be considered fully justified only if it is justified by the results of scientific and experimental research and approved by the relevant administrative documents of Ukrzaliznytsia the service life limit for wagons of this type. The existing method of technical diagnostics of passenger railway cars does not allow to fully assess the probability of extension of the service life of the car, because it does not take into account the peculiarities of damage to structural elements during operation. In the article the sequence of research of stresses in elements of a frame of a body of the passenger car of construction of KVN on the basis of standard tests is considered. The task of the study is to determine the sequence of calculation of stresses in the frame elements of the passenger car body of KСР (Kryukiv Carriage Plant) with a service life exceeding 41 years from the date of manufacture to assess strength and fatigue resistance by technical diagnostics and standard tests. It is concluded that the condition of the load-bearing metal structures of cars after long operation does not approach the limit. The residual resource was set at one of the minimum calculated values. If the results of calculations show that the resource is exhausted, the residual service life is determined by the results of bench tests for fatigue. The obtained practical and theoretical results make it possible to extend the service life of cars beyond that set by the manufacturer.


2012 ◽  
Vol 30 (1) ◽  
pp. 59-72 ◽  
Author(s):  
Piotr Barszcz

Research studies that are conducted by both the Air Force Institute of Technology (AFIT) and other domestic and foreign organizations indicate that investigations of corrosion phenomena present a very important factor with respect to prolongation of technical resources and operation of aircraft driven by their actual technical condition. The investigation of the corrosion degree and deterioration of protective coatings must be carried out in a systemic manner with thorough analysis of information that bring together the aircraft operation and the processes of corrosion and deterioration of protective coatings. The investigation must comprise measurements of the atmospheric corrosion in order to determine corrosive aggressiveness of the atmosphere and establish frequency and scope of corrosion inspection. Only the analysis of gathered information with its characteristics may guarantee safe operation of structural components of aircrafts according to their actual technical condition. This paper outlines the approach to corrosion investigation that is in place in AFIT.


Author(s):  
N. Radkevich ◽  
S. Sapronova ◽  
V. Tkachenko

In order to ensure the uninterrupted performance of passenger traffic, the task of ensuring the operation of rolling stock outside the extended service life, including passenger cars for the carriage of passengers, remains relevant. Based on this, there is a need for comprehensive research aimed at substantiating the possibility of ensuring operation while maintaining dynamic and strength characteristics. The article examines the residual life of load-bearing metal structures of passenger cars based on the results of technical diagnostics and standard tests. It is concluded that the condition of the load-bearing metal structures of passenger cars built by the Kryukiv Carriage Plant (KСP) after long operation does not approach the limit. The obtained practical and theoretical results make it possible to extend the service life of passenger cars for the construction of KCP beyond the factory set by 41 years.


2018 ◽  
Vol 216 ◽  
pp. 03011
Author(s):  
Sergey Barsukov ◽  
Sergey Pakhomov

The paper is aimed at developing a forecast model for estimating the service life of a diagnosed object based on the Neyman–Pearson method. It presents a procedure for selecting necessary and sufficient number of diagnostic indicators using the forecast model. The technique has been tested on the basis of a power transformer with a liquid dielectric. A condition-based operation strategy has been proposed for the transformer. According to this strategy, the iron impurity content in the dielectric liquid (oil) of the transformer should be measured every year of operation. Based on the forecast model, it is possible to calculate the variation of average risk (R) and a threshold value of iron impurity content in the transformer oil (k0) for each year of operation. Using these parameters, a reliable forecast model can be constructed to estimate the remaining service life of the transformer. The obtained relationships make it possible to identify a scientifically grounded stage in the service life of a diagnosed object, at which the number of measurable diagnostic indicators (indicators that are necessary for assessing the real technical condition of equipment) can be minimized.


Buildings ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 126 ◽  
Author(s):  
Beata Nowogońska

The perspective of maintaining residential buildings in adequate technical condition is one of the most important problems over the course of their service life. The aim of the work is to present issues connected with the methods of predicting the process of changes in performance characteristics over the entire period that a building, constructed using traditional technology, is operational. Identification of the technical situation consists of a prognosis based on the analytical form of the distribution function and probability density of building usability. The technical condition of a building results from its past, while familiarity with the condition is necessary to determine how the building will behave in the future. The presented predictive diagnostics of the performance characteristics of an entire building and its elements is an original methodology of describing the lifespan of a building. In addition to identifying the technical condition, its aim is also to aid in making decisions regarding maintenance works. The developed model of predicting changes in the performance characteristics of buildings, the Prediction of Reliability according to Exponentials Distribution (PRED), is based on the principles applied for technical devices. The model is characterized by significant limitations in its application due to the negligible influence of wear processes. In connection with the above, the Prediction of Reliability according to Raleigh Distribution (PRDD) was developed, where the carried-out processes of changes in the performance characteristics are described using Rayleigh’s distribution, and the building is a multi-element system. Model development would be incomplete without subjecting it to verification. Predicting the degree of the technical wear of load-bearing walls of a building is a form of checking the proposed PRED and PRRD models on the basis of data derived from periodical inspections of the research material. The developed model of the time distribution of the proper functioning of a building, presented as an image of the forecast of changes in the technical condition, can be applied to solving problems occurring in practice. The targeted approach to predicting the occurrence of damage will allow for optimal planning of maintenance works in buildings during their entire service life.


Author(s):  
G J Stein ◽  
P Múčka

This paper deals with simulation results of a planar passenger car model, supposed to simulate a ‘standard European saloon car’, with simple linear cushioned seats and a seated human model, which accounts for variation in the body weight. As excitation a short harmonic undulation (so called ‘rollete’) is used, sometimes encountered ahead of traffic-light-controlled road crossings. The simulation results indicate some dependence of the respective frequency response characteristics on the stipulated driver's and passenger's weights. Further large vertical acceleration values at axle hop frequencies are observed, which may under circumstances even exceed the standard gravity acceleration. These decrease with increased traversing velocity, say, above 50 km/h to bearable values. Further it is illustrated that the visibility of lights or signs may be momentarily impaired when accelerating from standstill at a road crossing with a large ‘rollete’ directly before the crossing.


2018 ◽  
Vol 22 (7) ◽  
pp. 66-71 ◽  
Author(s):  
M.A. Bandurin ◽  
I.F. Yurchenko ◽  
V.A. Volosukhin ◽  
V.V. Vanzha ◽  
Ya.V. Volosukhin

The analysis of the current approaches to the assessment of the technical condition of water supply facilities of irrigation systems has been carried out and the need has been established for improving the monitoring technology for reclamative water utilization system on the basis of the development of innovative automated instrument control methods that use the integral evaluation of the remaining service life of structures and the prediction of the service life of the facility. Created software-hardware complex automated diagnostic detection of latent defects providing designs and constructions underlying subgrade acoustic GPR and methods of nondestructive testing, determination of the location and geometric parameters of each structure element malfunctions. As part of the diagnostics, an assessment is carried out: the degree of abrasion, leaching, filtration of concrete elements of structures; indicators of frost resistance and water resistance, the volume of existing damage and the efficiency of the structure. The problem with the evaluation of the effectiveness of the creation and application of automated control systems for technological processes, caused by the lack of standards in the field of melioration regulating such calculations, is identified.


2016 ◽  
Vol 48 (3) ◽  
pp. 411-418
Author(s):  
V. V. Pokrovskii ◽  
V. G. Sidyachenko ◽  
V. N. Ezhov ◽  
S. B. Kulishov ◽  
A. N. Skritskii ◽  
...  

Author(s):  
P. Openko ◽  
V. Polishchuk ◽  
M. Mуronіuk ◽  
A. Kozyr

Maintenance of armaments and military equipment, implementation of a set of measures to maintain armaments and military equipment in working order are related to the need to solve the problem of ensuring the specified indicators of their efficiency, especially samples with long service life. Given the current state of the domestic armaments and military equipment park, it is important to study the experience of NATO member states in implementing adaptive maintenance and repair strategies, including maintenance and repair strategies. The aim of the article is to analyze the current state of use of adaptive strategies for maintenance and repair of weapons and military equipment in the world's leading countries with further substantiation based on its recommendations for their practical implementation during the organization of their operation in the Air Force of Ukraine. According to the results of research, a positive impact of the application of maintenance and repair strategy, including by solving the problem of minimizing the cost of operation of weapons and military equipment. As a result, substantiated and proposed the necessary conditions for the application of the strategy of their maintenance and repair, which are in service with the Armed Forces of Ukraine in technical condition, the implementation of which as an alternative to the use of service life (resource) of relevant samples control of the limit condition or the need for maintenance and repair of the product, which are accepted as a result of continuous (periodic) control of the parameters that determine the technical condition.


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