INTRO RLA, A Methodology for Assessing the Remaining Life of Major Electrical Equipment to Extend the Service Life beyond the Design in PHE ONWJ

2018 ◽  
Author(s):  
Rosihan Anwar ◽  
Bambang Pudjiantoro ◽  
Mukhtarus Bahroinuddin
Keyword(s):  
Service Life ◽  
Electrical Equipment ◽  
Remaining Life

scholarly journals Predicting the influence of the non-sinusoidal network mode on power transformers

2019 ◽  
Vol 114 ◽  
pp. 04005
Author(s):  
Ngo Van Cuong ◽  
Lidiia I. Kovernikova
Keyword(s):  
Service Life ◽  
Electric Power ◽  
Power Quality ◽  
Electrical Equipment ◽  
Operating Conditions ◽  
Transformer Oil ◽  
Power Transformers ◽  
Electrical Network ◽  
Electrical Networks ◽  
Current Harmonics

The parameters of electrical network modes often do not meet the requirements of Russian GOST 32144-2013 and the guidelines of Vietnam. In the actual operating conditions while there is the non-sinusoidal mode in electrical networks voltage and current harmonics are present. Harmonics result in overheating and damage of power transformers since they cause additional active power losses. Additional losses lead to the additional heat release, accelerating the process of insulating paper, transformer oil and magnetic structure deterioration consequently shortening the service life of a power transformer. In this regard there arises a need to develop certain scientific methods that would help demonstrate that low power quality, for instance could lead to a decrease in the electrical equipment service life. Currently we see a development of automated systems for continuous monitoring of power quality indices and mode parameters of electrical networks. These systems could be supplemented by characteristics calculating programs that give out a warning upon detection of the adverse influence of voltage and current harmonics on various electrical equipment of both electric power providers and electric power consumers. A software program presented in the article may be used to predict the influence of voltage and current harmonics on power transformers.

scholarly journals The thermal history and stress state of a fresh steam-pipeline influencing its remaining service life

2011 ◽  
Vol 15 (3) ◽  
pp. 691-704 ◽  
Author(s):  
Gordana Bakic ◽  
Vera Sijacki-Zeravcic ◽  
Milos Djukic ◽  
Stevan Maksimovic ◽  
Dusan Plesinac ◽  
...  
Keyword(s):  
Service Life ◽  
Elevated Temperatures ◽  
Operating Temperature ◽  
Life Assessment ◽  
Temperature History ◽  
Significant Variable ◽  
Remaining Life ◽  
Pipe Bend ◽  
Steam Pipeline ◽  
Remaining Life Assessment

The service life of thick-walled power plant components exposed to creep, as is the case with pipelines of fresh- and re-heated steam, depend on the exhaustion rate of the material. Plant operation at elevated temperatures and at temperatures below designed temperatures all relates to the material exhaustion rate, thus complicating remaining life assessment, whereas the operating temperature variation is a most common cause in the mismatching of real service- and design life. Apart from temperature, the tube wall stress is a significant variable for remaining life assessment, whose calculation depends on the selected procedure, due to the complex pipeline configuration. In this paper, a remaining life assessment is performed according to the Larson-Miller parametric relation for a ?324?36 pipe bend element of a fresh steam-pipeline, made of steel class 1Cr0.3Mo0.25V, after 160 000 hours of operation. The temperature history of the pipeline, altogether with the pipe bend, is determined based on continuous temperature monitoring records. Compared results of remaining life assessment are displayed for monitored temperature records and for designed operating temperature in the same time period. The stress calculation in the pipe bend wall is performed by three methods that are usually applied so to emphasize the differences in the obtained results of remaining life assessment.

Technology for Water Economy Monitoring of Technical State of Closed Drainage on Irrigation Systems

2018 ◽  
Vol 931 ◽  
pp. 214-218 ◽  
Author(s):  
Mikhail A. Bandurin ◽  
Victor A. Volosukhin ◽  
Vladimir V. Vanzha
Keyword(s):  
Service Life ◽  
Technical State ◽  
Remaining Life ◽  
Irrigation Systems ◽  
Operational Capability ◽  
Closed Drainage ◽  
Current Survey ◽  
Automation Technology ◽  
The Given

Technical state of closed drainage on irrigation systems owing to well-established, conditions for the country's economy development was without due attention beginning since the 90s of the 20th century and this was negatively reflected of their operational capability nowadays. Current survey procedures of closed drainage on irrigation systems are directed at evaluating, as a whole, serviceability of structure system elements for the further operation. When conducting survey a number of questions to the methods and ways to detect faults and defects as well as to forecast remaining life operational capability for the given period of time have been arisen. The objective to develop an automation technology for multifactor survey of closed drainage of irrigation systems is evaluating actual technical state of structural elements and the main equipment by the methods of non-destroying instrumental control, determination of remaining life operational capability of their elements as well as determination of safety deficit to evaluate possibilities of continuing operation above the fixed service life. The positive results of the above evaluation are the basis to prepare a structure for prolongation of its service life.

scholarly journals Prediction of Remaining Life for Bridge Decks Considering Deterioration Factors and Propose of Prioritization Process for Bridge Deck Maintenance

2020 ◽  
Vol 12 (24) ◽  
pp. 10625
Author(s):  
Ki Hwan Kim ◽  
Moon S. Nam ◽  
Hoon Hee Hwang ◽  
Ki Yong Ann
Keyword(s):  
Service Life ◽  
Bridge Deck ◽  
Bridge Decks ◽  
Highway Bridges ◽  
Performance Degradation ◽  
Remaining Life ◽  
Remaining Service Life ◽  
Prioritization Process ◽  
Optimizing Design ◽  
Inspection Data

Aged highway bridges have become substantially prevalent in recent years. Moreover, combined deterioration, caused by using deicing agents in winter, has led to increased bridge maintenance costs. Accordingly, to extend the service life of bridge decks, this study utilized actual inspection data and major deterioration factors to derive the remaining service life of bridge decks. Based on this study, the following three factors are selected: deicing agent exposure grade, pavement condition state, and surface improvement status. Performance degradation curves were derived for 11 cases that considered the representative three deterioration factors, and the performance degradation of decks was examined for each deterioration factor. Additionally, a process to determine maintenance priorities, using the current condition of highway bridges and the deterioration factors of individual bridges, was proposed. The maintenance demand was predicted based on the end of deck life, which indicated that the demand for deck replacement will sharply increase in 15 years, and that the decks of more than 2000 bridges will reach the end of life in 40 years. Furthermore, this paper proposes a process for prioritizing the maintenance of approximately 9000 highway bridge decks. By applying the prioritization process for bridge deck maintenance to the bridge deck, not only can the life of the bridge deck be extended, but also environmental pollution can be minimized. Additionally, an optimizing design for bridge decks, by considering the remaining life and deterioration factors, can be possible. Therefore, it is expected that the sustainability of the bridge deck can be accomplished.

scholarly journals Research on Life Prediction of Fan Spindle Bearing Based on Gated Recurrent Unit Neural Network

2021 ◽  
Vol 261 ◽  
pp. 01039
Author(s):  
Jianeng Ma
Keyword(s):  
Service Life ◽  
Life Prediction ◽  
Learning Algorithm ◽  
Data Sets ◽  
Remaining Life ◽  
Predictive Algorithm ◽  
Remaining Service Life ◽  
Spindle Bearing ◽  
The Relationship ◽  
Gated Recurrent Unit

In order to solve the problems of redundancy calculation and inefficiency of traditional machine learning algorithm in dealing with large amount of historical data of fan, a new predictive algorithm based on gated recurrent unit (GRU) is proposed to predict the remaining service life of fan spindle bearing. Firstly, the vibration history data of the main shaft bearing of the fan is analyzed to find out the relationship between the characteristic value and the remaining life, and the characteristic parameters which can reflect the remaining life are selected; Then, GRU is used to build the remaining service life prediction model of spindle bearing, and the main parameters of the model are adjusted to improve the prediction accuracy of the model. Compared with long short term (LSTM) algorithm, GRU is an effective tool to deal with a large number of data sets.

Risk-based corrosion assessment and refurbishment of marine structures

2018 ◽  
Vol 58 (1) ◽  
pp. 60
Author(s):  
Stephan Dickinson ◽  
Kerryn Wilson ◽  
Ali Sarandily ◽  
René van der Werf ◽  
Steve Sheen ◽  
...  
Keyword(s):  
Service Life ◽  
Phase 1 ◽  
Phase 2 ◽  
Remaining Life ◽  
Liquefied Petroleum Gas ◽  
Original Design ◽  
Marine Structures ◽  
Corrosion Rates ◽  
Design Life ◽  
Inspection Techniques

This paper outlines a holistic, risk-based approach to managing the service life of existing liquefied natural gas (LNG) and liquefied petroleum gas (LPG) marine structures in Western Australia. The structures have been in service since 1989 (LNG) and 1995 (LPG) and are nearing the end of their original design life. The objective of this approach is to extend the design life for an additional 20 years to 2040. The risk-based assessment (RBA) process is composed of three main steps undertaken in sequence to identify and quantify refurbishment requirements for the timeframe. A two-campaign approach was considered, the first being in 2019 (Phase 1) and the second in 2030 (Phase 2). The RBA process combines innovative and conventional inspection techniques with a detailed desktop structural assessment of the remaining life of the structures’ individual components to enable an informed decision to be made on the refurbishment requirements for each campaign. The results of the stepped RBA process demonstrate the effectiveness of the approach to define and manage a refurbishment program that achieves the required extended service life of the structures to 2040. The RBA process enabled the first campaign’s scope to be minimised through detailed analysis and calculation of residual design life of each critical member, deferring most of the refurbishment scope to the second campaign in 2030. The study has recommended implementation of a corrosion rate trial to verify the assumed corrosion rates for the jetty structures. Environmental monitoring stations and test coupons installed on the jetty for a five-year period will confirm the actual deterioration rates specific to the jetty structures. Confirmation of actual deterioration rates may reduce uncertainty in the values over those currently assumed in the study and positively affect the identified Phase 2 refurbishment scope.

scholarly journals A Supercapacitor-Based Method to Mitigate Overvoltage and Recycle the Energy of Pantograph Arcing in the High Speed Railway

Energies ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1214
Author(s):  
Cuidong Xu ◽  
Zhu Chen ◽  
Ka Cheng ◽  
Xiaolin Wang ◽  
Ho Ho
Keyword(s):  
Service Life ◽  
High Speed ◽  
Electronic System ◽  
Electrical Equipment ◽  
Power Electronic ◽  
High Speed Railway ◽  
Electromagnetic Transient ◽  
Bidirectional Converters ◽  
Devices And Instruments ◽  
Simulation Results

The pantograph arcing phenomenon may shorten the service life of a pantograph and even destroy onboard devices and instruments, due to the irregular motions of the train and the intermittent line–pantograph disconnection. This paper points out that abrupt inductive energy from the magnetizing inductance of the traction transformer can lead to an electromagnetic transient process with unexpected overvoltage across it. Further, a supercapacitor-based power electronic system is proposed, which can not only redirect the inductive energy to the supercapacitor pack through bidirectional converters but also mitigate the overvoltage across the main electrical equipment when pantograph arcing occurs. Simulation results show the overvoltage could be reduced and the energy stored in the supercapacitor which could also be used to provide energy for sensors or other devices.

How to determine the remaining life of machine parts

2020 ◽  
pp. 50-57
Author(s):  
Vyacheslav I. Chernoivanov ◽  
Vyacheslav A. Denisov ◽  
Aleksey A. Solomashkin
Keyword(s):  
Service Life ◽  
Residual Life ◽  
Interval Estimation ◽  
Probability Of Failure ◽  
Technical Condition ◽  
Research Purpose ◽  
Interval Estimate ◽  
Remaining Life ◽  
Maintenance And Repair ◽  
Machine Parts

The article presents three strategies for maintenance and repair of machines that control the pre-selected and justified parameters of the technical condition of the machine, as well as the costs of eliminating failures for these strategies and the possibility of reducing them. (Research purpose) The research purpose is to identify the most effective way to determine the residual life of machine parts. (Materials and methods) The article proposes a strategy for maintenance and repair of machines, in which a special place is occupied by ways of reducing the mechanical friction losses, increasing the efficiency of the machine and the service life of its parts. The article notes that in order to meet the service life, it is necessary to monitor their remaining life visually or using appropriate sensors. In order to determine the remaining resource in more accurately way, we suggested that it would be measured several times, preferably using different methods or devices. Authors designed a computer program that allows to estimate the remaining resource using an interval estimation of random values for a given probability of failure-free operation of the machine part. The plunger pairs of a high-pressure fuel pump were chosen as the object of research. As a diagnostic parameter that characterizes the technical condition of the pump, its starting cycle feed was used, the value of which was determined on different stands. (Results and discussion) Article presents the values of the average resources of the plunger pairs, their dispersion around the corresponding average values, and calculated their average residual resource as an interval estimate for a given probability of failure-free operation. (Conclusions) The research results have shown a possibility of using the residual resource as the basis of the proposed strategy for maintenance and repair of machines based on minimizing the residual resource of their parts. The most important unsolved task for this strategy remains the selection and justification of primary diagnostic sensors for assessing the residual life of machine parts.

scholarly journals Evaluation of electrical equipment service life on the basis of its status index trend

2017 ◽  
Vol 25 ◽  
pp. 04004 ◽  
Author(s):  
Alexander Nazarychev ◽  
Alexey Tadzhibaev ◽  
Dmitry Andreyev
Keyword(s):  
Service Life ◽  
Electrical Equipment ◽  
Status Index

scholarly journals The estimation of ship cable condition by the means of measuring its insulation characteristics

Vestnik MGTU ◽  
2020 ◽  
Vol 23 (4) ◽  
pp. 335-344
Author(s):  
A. B. Vlasov ◽  
S. A. Buev
Keyword(s):  
Dielectric Loss ◽  
Service Life ◽  
Thermal Aging ◽  
Electrical Equipment ◽  
The State ◽  
Loss Angle ◽  
Linear Change ◽  
Cable Insulation ◽  
Diagnostic Parameters ◽  
Dielectric Loss Angle

Timely detection of defects in electrical equipment and cable network is required for the ensuring the fire safety of a modern marine vessel. The method of continuous monitoring of the resistance value of cable insulation is not very informative and is not applicable for assessing the service life of cables and predicting their replacement during operation and repair. Currently the problem of developing modern non-destructive methods of insulation control is very urgent in order to determine the operability of the cable, search for diagnostic parameters characterizing the state of insulation during prolonged aging, as well as the introduction of traditional methods of diagnostics of electrical equipment that have shown their effectiveness at the facilities of the coastal infrastructure. A promising solution for this problem is a method for monitoring the values of the tangent of the dielectric loss angle tgδ of cable insulation using devices that allow registering parameters with high accuracy. In this study the determination of changes in the parameters of a ship cable subjected to accelerated thermal aging at temperatures 120-130 °C has been made. The tgδ measurements of the cable sheath have been carried out using the Tangent-2000 insulation meter. The tests have shown that aging of cable hose insulation is accompanied by a non-linear change in tgδ; at certain values of the tangent of dielectric loss angle, visible cracks appear indicating the onset of an emergency condition of the cable. The nature of the change in the parameter tgδ is explained by the occurrence of reactions of oxidative dehydrochlorination of polychloroprene in the process of thermal aging of insulation and changes in its mass. Thus, the tangent of the dielectric loss angle can be one of the diagnostic parameters for assessing the state of the insulation of the ship's cable and predicting its service life.

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