scholarly journals INVESTIGATION OF RESIDUAL RESOURCE OF SPECIAL RAILWAY VAGON

2021 ◽  
Vol 1 (37) ◽  
pp. 50-58
Author(s):  
N. Radkevich
Keyword(s):  
Service Life ◽  
Residual Life ◽  
Technical Diagnostics ◽  
Residual Service Life ◽  
Passenger Cars ◽  
Scientific Publications ◽  
Load Bearing ◽  
Metal Structures ◽  
Long Operation ◽  
Standard Tests

The article examines the residual life of load-bearing metal structures (NMC) of special cars for the transportation of special contingent on the basis of the results of technical diagnostics and standard tests. Most scientific publications investigate the increase in the service life of different types of passenger cars by improving their design properties. The following methods are used in the study: resetting from wedges, resource tests for impact strength, impact tests, static strength tests. On the basis of carrying out technical diagnostics and standard tests the possibility of establishment of new appointed service life of cars is defined. The residual resource was set at one of the minimum calculated values obtained by mathematical dependence to calculate the residual service life. When determining the residual resource during the standard tests, the evaluation of the fatigue resistance margin was performed taking into account the stress of the load-bearing structures of the car during the tests. It is concluded that the condition of load-bearing metal structures of special wagons for transportation of special contingent after long operation does not approach the limit. The obtained practical and theoretical results make it possible to extend the service life of special wagons for the transportation of special contingent beyond the established by the manufacturer.

STUDY OF RESIDUAL RESOURCE AND ESTABLISHMENT OF THE LIMIT LIFE OF NON-PURCHASER PASSENGER CARS OF CONSTRUCTION OF KVZ

2020 ◽  
pp. 54-62
Author(s):  
N. Radkevich ◽  
S. Sapronova ◽  
V. Tkachenko
Keyword(s):  
Service Life ◽  
Residual Life ◽  
Rolling Stock ◽  
Technical Diagnostics ◽  
Passenger Cars ◽  
Load Bearing ◽  
Metal Structures ◽  
Passenger Traffic ◽  
Long Operation ◽  
Theoretical Results

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.

scholarly journals IMPROVEMENT OF METHODS OF TECHNICAL DIAGNOSIS OF PASSENGER RAILWAY CARS

2021 ◽  
Vol 1 (38) ◽  
pp. 80-87
Author(s):  
M. Radkevych ◽  
S. Sapronova ◽  
N. Braikovska ◽  
V. Tkachenko
Keyword(s):  
Service Life ◽  
Technical Diagnostics ◽  
Residual Service Life ◽  
Structural Elements ◽  
Passenger Car ◽  
Metal Structures ◽  
Long Operation ◽  
Theoretical Results ◽  
Residual Service ◽  
Standard Tests

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.

Functional and operational risk as a criterion for assessing the durability of an autonomous energy system

2019 ◽  
Vol 12 (1) ◽  
pp. 56-62 ◽  
Author(s):  
A. O. Nedosekin ◽  
A. V. Smirnov ◽  
D. P. Makarenko ◽  
Z. I. Abdoulaeva
Keyword(s):  
Service Life ◽  
Structural Reliability ◽  
Residual Life ◽  
Fuzzy Random Variable ◽  
Operational Risk ◽  
Energy System ◽  
Technical System ◽  
Residual Service Life ◽  
Technological Parameters ◽  
Residual Service

The article presents new models and methods for estimating the residual service life of an autonomous energy system, using the functional operational risk criterion (FOR). The purpose of the article is to demonstrate a new method of durability evaluation using the fuzzy logic and soft computing framework. Durability in the article is understood as a complex property directly adjacent to the complex property of system resilience, as understood in the Western practice of assessing and ensuring the reliability of technical systems. Due to the lack of reliable homogeneous statistics on system equipment failures and recoveries, triangular fuzzy estimates of failure and recovery intensities are used as fuzzy functions of time based on incomplete data and expert estimates. The FOR in the model is the possibility for the system availability ratio to be below the standard level. An example of the evaluation of the FOR and the residual service life of a redundant cold supply system of a special facility is considered. The transition from the paradigm of structural reliability to the paradigm of functional reliability based on the continuous degradation of the technological parameters of an autonomous energy system is considered. In this case, the FOR can no longer be evaluated by the criterion of a sudden failure, nor is it possible to build a Markov’s chain on discrete states of the technical system. Assuming this, it is appropriate to predict the defi ning functional parameters of a technical system as fuzzy functions of a general form and to estimate the residual service life of the technical system as a fuzzy random variable. Then the FOR is estimated as the possibility for the residual life of the technical system to be below its warranty period, as determined by the supplier of the equipment.

Expected residual service life of reinforced concrete structures from current strength considerations

2019 ◽  
Vol 22 (7) ◽  
pp. 1631-1643
Author(s):  
Sushil Kumar Dhawan ◽  
Abhinav Bindal ◽  
Suresh Bhalla ◽  
Bishwajit Bhattacharjee
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Residual Life ◽  
Concrete Structures ◽  
Present Condition ◽  
Material Strength ◽  
Reinforced Concrete Structures ◽  
Residual Service Life ◽  
Remaining Service Life ◽  
Residual Service

Concrete is primarily used in the form of reinforced concrete for construction of buildings, bridges and other important structures. Due to normal usage and environmental effects, the structure would gradually deteriorate. The actual residual life needs to be worked at a given time vis-à-vis the design life of the structure, commensurate with the fulfilment of essential requirements of structural integrity and safety and from strength as well as serviceability considerations. Requirements for residual life assessment would depend upon the current parameters, such as the residual cross-sectional area of concrete as well as steel, Young’s modulus of elasticity and the in situ material strength of the constituent materials, namely, concrete and steel. This article aims to develop a rigorous methodology for expected remaining service life of a reinforced concrete structure from wind/seismic considerations, based on the present condition of the structure encompassing the residual material strength and the residual reinforcement/sectional areas. The methodology development section is followed by an illustrative example and a parametric study involving a 10-storeyed reinforced concrete building frame under wind and earthquake loads. Influences of various parameters such as concrete strength and residual rebar area on the expected remaining service life are studied in detail. The proposed methodology provides a simple but rational estimation of the residual service life for reinforced concrete structures.

scholarly journals Technical condition of welded load-bearing metal structures of operated agricultural hoisting cranes

2020 ◽  
Vol 175 ◽  
pp. 11005
Author(s):  
Alexander Scherbakov ◽  
Anna Babanina ◽  
Ivan Kochetkov ◽  
Pavel Khoroshilov
Keyword(s):  
Plastic Deformation ◽  
Metal Structure ◽  
Technical Condition ◽  
Technical Diagnostics ◽  
Low Alloy Steels ◽  
Low Carbon ◽  
Load Bearing ◽  
Metal Structures ◽  
Elastic Plastic ◽  
Alloy Steels

The paper considers the methodology for assessing the technical condition of welded load-bearing metal structures of operated agricultural hoisting cranes. In the course of the study, the relationship between structural, mechanical and magnetic parameters was established during cyclic elastic-plastic deformation of low-carbon and low alloy steels. Based on the analysis, it was concluded that the dependence of the minimum values of the magnetic parameter on the acting stresses Нр(σ) is influenced by the metal structure and its chemical composition. It has been established that the coarser-grained structure of the studied steels under elastic-plastic deformation contributes to a shift in the minimum values of Нр towards lower acting stresses; an increase in the strength characteristics of steels shifts the minimum of Нр toward large values of s, which must be taken into account when conducting technical diagnostics of the elements of the operating metal structures of hoisting cranes. Based on the results of the study, a method for determining the acting stresses in the elements of the metal structures of hoisting cranes was developed, which, by the nature and magnitude of the change in the residual magnetization of the scattering field during their stepwise loading (unloading), allows judging the magnitude of the acting stresses. The work also presents a methodology for assessing the technical condition of welded load-bearing metal structures of hoisting cranes based on the integrated use of passive flux-gate and other control methods, which allows determining the acting stresses used in strength calculations in the identified hazardous zones of concentration of stresses in the elements of metal structures.

INVESTIGATION OF CORROSION WEAR OF SUPPORTING METAL STRUCTURES OF FREIGHT CARS DURING MEASURES TO EXTEND THE TERM OF SERVICE

2020 ◽  
pp. 43-53
Author(s):  
D. Bulich ◽  
S. Sapronova ◽  
V. Tkachenko ◽  
A. Koshel
Keyword(s):  
Statistical Analysis ◽  
Residual Life ◽  
Corrosion Wear ◽  
Load Bearing ◽  
Metal Structures ◽  
Individual Approach ◽  
Freight Car

All elements of load-bearing metal structures of freight cars are subject to corrosion wear. In this article, a statistical analysis of corrosion wear for each element of load-bearing metal structures. Damage to load-bearing metal structures of gondola cars taking into account corrosion wear is considered. Measures to increase the possible maximum corrosion wear, which can be used to predict the residual life and structural finishing of the elements of load-bearing metal structures. Cracks and fractures that are not detected in time, which turn into through-corrosion during operation, have a great impact on corrosion. To determine the corrosion of the freight car requires an individual approach to each element of the load-bearing structures of the car, taking into account the performance and time of repair.Studies have shown that half of freight cars were operated with corrosion of some elements of load-bearing metal structures more than 30%. This shows the possibility of increasing the tolerance of the threshold of corrosion wear of cars, which will affect the ability to reduce the exclusion of freight cars from the inventory.

Modernization of eight-axle tank car for alkylbenzenesulfonic acid with extension of service life

2020 ◽  
pp. 41-46
Author(s):  
Nikita Alexandrovich Bityutskiy ◽  
◽  
Vladimir Viktorovich Galov ◽  
Lyudmila Valerievna Tsyganskaya ◽  
Alexander Igorevich Bondarenko ◽  
...  
Keyword(s):  
Finite Element ◽  
Statistical Analysis ◽  
Service Life ◽  
Finite Element Model ◽  
Element Model ◽  
Technical Diagnostics ◽  
Residual Service Life ◽  
Basic Design ◽  
Analysis Of Failures ◽  
Residual Service

The paper considers an issue of extending the service life of eight-axle tank cars for alkylbenzenesulfonic acid by modernization of car design. The modernization included technical diagnostics of cars with basic design, repair or replacement of car parts and equipment, calculations and tests of modernized car design. During the technical diagnostics of cars the authors carried out a statistical analysis of failures, determined a speed of corrosion of car elements in operation and predicted a residual service life. On the basis of results of technical diagnostics the authors created a finite element model of the car, formulated normative calculations and carried out necessary tests on natural samples of cars. As a result, calculations and tests confirmed the reliability of gained data, justified the service life of the modernized car design.

scholarly journals THE DETERMINATION OF THE RESIDUAL LIFE OF BUILDING STEEL STRUCTURES BY THE RELIABILITY INDEX INDICATORS

2021 ◽  
pp. 28-55
Author(s):  
S.V. Kolesnichenko ◽  
◽  
Y.V. Selyutyn ◽  
D.F. Obolonkov ◽  
O.S. Karapanov ◽  
...  
Keyword(s):  
Service Life ◽  
Structural Steel ◽  
Reliability Index ◽  
Residual Life ◽  
Steel Structures ◽  
Life Extension ◽  
Design Stage ◽  
Residual Service Life ◽  
Term Operation

In order to assess the operational safety of steel constructions, the paper analyzes the principles of calculating the safety of structural steel constructions with consideration for the reliability index β at all phases of constructions operation and the design fundamentals of the reliability index β for both new constructions (at the design stage) and structural steel constructions in the conditions of the long-term operation. The task of safety and reliability calculations, first of all, consists in assigning normalized safety parameter values, i.e. normalizing the reliability index, the value of which should be strictly related to the consequence classes (CC), which are determining for setting the reliability coefficients for further calculations while designing the constructions. The article considers the calculation values β of the reliability index for constructions operated beyond the time limit for operation, with accumulated defects and damages. To improve the mechanism for calculating the reliability index value for the constructions operated beyond the maximum operating limit, with accumulated defects and damages, several tasks were set to determine such values β of the reliability index below which the construction is no longer considered to be operational and to define the reliability index values β for possible performance of renovation works (reconstruction, refurbishment) to strengthen and extend the remaining structural lifetime. Thus, emphasizing all of the aforementioned, the main conclusions to the article should be specified: at the stage of solving the issue of calculating the reliability index for structures being operated over the projected service life, with damages and initial defects accumulated during the operation period, it is required to perform their review and determine two main criteria for solving the issue of determining the reliability index, namely: to set such values of the reliability index below which the structure will be no longer operational, to define and set such values of the reliability index at which it is possible to carry out renovation works on steel structures, their reconstruction or repair. Considering the possibility of changing the reliability index compared to a new structure, given that the residual service life may be shorter than the design one, taking into account the economic factors and factors of probability of losing a person’s life, setting of such reliability index values is necessary for further possibility of the service life extension of a structure and determination of its residual life.

scholarly journals TECHNICAL DIAGNOSIS OF TRACTION ROLLING STOCK. FEATURES OF APPLICATION OF THE METHOD OF EVALUATION OF THE RESIDUAL RESOURCE OF SUPPORTING METAL STRUCTURES

2021 ◽  
pp. 43-52
Author(s):  
M.O. Bahrov ◽  
Keyword(s):  
Service Life ◽  
Key Words ◽  
Rolling Stock ◽  
Operating Life ◽  
Load Bearing ◽  
Metal Structures ◽  
Technical Diagnosis ◽  
Certification Procedure ◽  
Experimental Project ◽  
Method Of Evaluation

Recently there is the intrest increasing in admission of private locomotives to the operating on the particular headings of public railways. At the initiative of Ministry of Infrastructure the Resolution of the Cabinet of Ministers of Ukraine dated 04.12.2019 № 1043 “About implementation of experimental project on the admission of private locomotives to the operating on the particular headings of public railways” is confirmed. The experimental project is designed for two years, it means till 04.12.2021. According to the requirements of the “Temporary Regulations on the procedure of the admission of private locomotives to the operating on the particular headings of public railways” approved by the Order of the Ministry of Infrastructure of Ukraine dated 04.03.2020 № 191, defined the requirements for applicants (enterprises), rolling stock, their maintanence and repair, personnel. In particular, it is established that private locomotives are allowed to operate on public railways with the availability of a conformity certificate. Private locomotives, that are applied for participation in experimental project, as a rule, are not new, and have certain service life, respectively, certain performance characteristics, remaining operating life of load-bearing metal structures, so the certification procedure of locomotives has some particularities and should cover, exept common measures of certification, measures of technical diagnoses, i.e. with the assessment of final resources of load-bearing metal struc-tures. Key words: experimental project, allowance for private locomotives, a conformity certificate, technical diagnoses.

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