Evaluation of residual operating life of pipeline based on metal strain ageing

2017 ◽  
Author(s):  
N. L. Zaitsev ◽  
S. A. Silvestrov ◽  
K. M. Gumerov ◽  
B. A. Bulykin
Keyword(s):  
Operating Life ◽  
Strain Ageing ◽  
Metal Strain ◽  
Residual Operating Life

scholarly journals Assessment of Residual Service Life of Cast Bodies of Control Valves of 220 MW Power Units

2020 ◽  
Vol 23 (4) ◽  
pp. 22-28
Author(s):  
Olha Yu. Chernousenko ◽  
◽  
Dmytro V. Ryndiuk ◽  
Vitalii A. Peshko ◽  
◽  
...  
Keyword(s):  
Service Life ◽  
Control Valve ◽  
Steam Turbines ◽  
Operating Life ◽  
Control Valves ◽  
Intermediate Pressure ◽  
Operating Modes ◽  
Residual Operating Life ◽  
Start Ups ◽  
Total Damage

In the regulatory documents of the Ministry of Energy and Coal Industry of Ukraine, the beyond-design operating life of the high-energy equipment of 220 MW power units is limited to the operating life of 220 thousand hours and 800 start-ups. To date, the high-temperature cast bodies of the control valves for the high- and intermediate-pressure cylinders of the K-200-130 200 MW steam turbines of DTEK Lugansk TPP have operated about 305–330 thousand hours with the total number of start-ups from 1438 to 1704, which exceeded the beyond-design service life characteristics. Therefore, it is necessary to assess the residual operating life of the control valve bodies of the high- and intermediate-pressure cylinders of K-200-130 steam turbines in order to determine the possibility of their further operation. These calculations were carried out on the basis of our earlier studies of the thermal and stress-strain states of cast turbine equipment. This paper establishes the values of stress intensity amplitudes, the values having been reduced to a symmetric loading cycle for the most typical variable operating modes. Using the experimental low-cycle fatigue curves for the 15Kh1M1FL steel, we established the values of the permissible number of start-ups and the cyclic damage accumulated in the base metal. We also determined the value of the static damage accumulated in the course of stationary operating modes according to our previously obtained experimental data on the long-term strength of the 15Kh1M1FL steel. The calculations showed that the total damage to the control valve bodies of the K-200-130 steam turbine of power unit 15 of DTEK Lugansk TPP is 97 and 98%. The residual operating life of the metal of the control valves of high-pressure cylinders is practically exhausted, being equal to 10 thousand hours. The residual life of the control valves of intermediate- pressure cylinders is 7 thousand hours, i.e. it is also practically exhausted, with safety factors for the number of cycles and strains at the level of 5 and 1.5, as well as the permissible 370,000 operating hours of the metal. With an increase in the permissible operating life of the metal to 470 thousand hours, according to experimental studies of Igor Sikorsky KPI, the total damage to the metal of cast valve bodies is reduced to 80%, and the residual metal life increases to 79,000 h and 75,000 h for the control valves of the high- and intermediate-pressure cylinders, respectively.

Structural principles of a universal platform for continuous monitoring of the technical condition of infrastructure facilities

2020 ◽  
Vol 6 (4) ◽  
pp. 484-498
Author(s):  
G. V. Osadchiy ◽  
◽  
A. V. Shinkarenko ◽  
D. G. Plotnikov ◽  
A. V. Banite ◽  
...  
Keyword(s):  
Continuous Monitoring ◽  
Technical Condition ◽  
Point Of View ◽  
Transport Infrastructure ◽  
Monitoring Systems ◽  
Operating Life ◽  
Optimal Sequence ◽  
Failure Conditions ◽  
Monitoring Technologies ◽  
Residual Operating Life

The article discusses the development of monitoring technologies for industrial and transport infrastructure facilities. The importance of monitoring systems for improving the engineering facility maintenance technologies, as well as the ability to determine pre-failure conditions, predict further changes, and determine the residual operating life, is noted. The authors analyze approaches to the implementation of monitoring systems from the point of view of an optimum confi guration. A list of criteria for evaluating the efficacy of the considered design approaches is provided. Recommendations are given for rational designing of monitoring systems and the optimal sequence of actions is determined for creating a universal platform for continuous monitoring of the condition of engineering facilities. The concept of a universal platform for continuous monitoring for infrastructure facilities in the construction, transport and industry is proposed

scholarly journals COMPARATIVE ANALYSIS OF NONLINEAR MODELS FOR PREDICTING RESIDUAL OPERATING LIFE AND OPERABILITY OF THE STRUCTURAL ELEMENTS OF RESIDENTIAL BUILDINGS

Vestnik MGSU ◽  
2016 ◽  
pp. 10-17
Author(s):  
Natal’ya Valer’evna Golovina ◽  
Gennadiy Dmitrievich Shmelev
Keyword(s):  
Comparative Analysis ◽  
Logistic Model ◽  
Residual Life ◽  
Nonlinear Models ◽  
Residential Buildings ◽  
Building Structures ◽  
Structural Elements ◽  
Operating Life ◽  
Residual Operating Life ◽  
General Method

A number of researchers are working on the creation of a general method for forecasting operability and residual life of engineering constructions of buildings and structures of different purposes using the models of nonlinear physical wear development. The authors analyzed two approaches to forecasting operability and estimating residual operating life of structural elements of residential houses using nonlinear models of the changes in physical wear of building structures basing on forecast logistic model. The description of the differences in the approaches to forecasting and advantages of one method compared to another are given. As a result of the conducted analysis the authors recommend the most accurate model for making predictions and estimation of residual operating life of building structures.

scholarly journals Method of dependability assessment of spacecraft in design and engineering studies

Dependability ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 3-8
Author(s):  
V. Ya. Gecha ◽  
R. N. Barbul ◽  
N. I. Sidniaev ◽  
Yu. I. Butenko
Keyword(s):  
Organizational Design ◽  
Estimation Method ◽  
External Factors ◽  
Operating Life ◽  
Dependability Analysis ◽  
Technical Specifications ◽  
Classical Computing ◽  
Residual Operating Life ◽  
Design And Manufacture ◽  
Lifetime Extension

The paper examines the matters of operational dependability of space systems (SS), efficiency of complex systems, use of redundancy in spacecraft (SC) design. It presents methods of predicting the dependability of designed devices, design of devices with desired dependability and comparison of dependability of various SS. For that purpose, the authors set forth the fundamentals of the dependability theory for SS design, methods of collection and processing of data of equipment dependability based on the results of operation and special dependability tests. Methods, mathematical models are developed, the equipment architecture at the stage of design and manufacture is analyzed. The paper also cites the design ratios for various tested types of redundancy, lifetime extension of SC units based on the residual operating life estimation method. The existing methods of dependability analysis are classified and examined. The authors outline the problems of ambiguity of information of the input data in case of classical computing. The effect of nominal deviations of the external effects, irregularity of the failure rate, non-linear nature of the effect of external factors on the dependability are examined. The paper also takes a look at the way the external factors affect the dependability and the degree to which such factors are taken into consideration in the existing methods. It is noted that the qualitative, technical and organizational (design and software) requirements for dependability in the technical specifications for each stage of elements and SS development, shall be observed and confirmed at the respective stage of activities. The paper presents the methods of estimation of technical item operating life with the focus on those based on the physical premises of operating life depletion. Attention is drawn to the importance of the economic aspect in the research dedicated to SS lifetime extension.

scholarly journals ESTIMATING THE RESIDUAL OPERATING LIFE OF WOODEN STRUCTURES IN HIGH HUMIDITY CONDITIONS

2020 ◽  
Vol 5 (1) ◽  
pp. 10-19
Author(s):  
Aleksandr Chernykh ◽  
◽  
Dmitry Korolkov ◽  
Denis Nizhegorodtsev ◽  
Tatiana Kazakevich ◽  
...  
Keyword(s):  
High Humidity ◽  
Operating Life ◽  
Residual Operating Life ◽  
Wooden Structures
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