To provide some feasible condition-based maintenance (CBM) decision making methods for civil aeroengine, firstly, the theory of aeroengine CBM decision making is described. The proportional intensity(PI) model is ...To provide some feasible condition-based maintenance (CBM) decision making methods for civil aeroengine, firstly, the theory of aeroengine CBM decision making is described. The proportional intensity(PI) model is established based on the reliability and condition monitoring data. According to the model, the decision making methods are proposed for the optimal preventive maintenance(PM) interval and removal. Then, the time on wing (TOW) is predicted by collecting actual data based on the engine age and operating conditions. Finally, an example of a fleet for CF6-80C2 engines is illustrated. It shows that sufficient engine operation data are the key of accurate decision making. Results indicate that the CBM decision making methods are helpful for engineers in airlines to control engine maintenance actions and TOW, thus decreasing risks and maintenance costs.展开更多
The existing maintenance strategies of offshore wind energy are reviewed including the specific aspects of condition-based maintenance, focusing on three primary phases, namely, condition monitoring, fault diagnosis a...The existing maintenance strategies of offshore wind energy are reviewed including the specific aspects of condition-based maintenance, focusing on three primary phases, namely, condition monitoring, fault diagnosis and prognosis, and maintenance optimization. Relevant academic research and industrial applications are identified and summarized. The state of art, capabilities,and constraints of condition-based maintenance are analyzed. The presented research demonstrates that the intelligent-based approach has become a promising solution for condition recognition, and an integrated data platform for offshore wind farms is significant to optimize the maintenance activities.展开更多
The development process of high-voltage electric power equipment maintenance was introduced. It is pointed out that the trend of high-voltage electric power equipment maintenance is so called condition-based maintenan...The development process of high-voltage electric power equipment maintenance was introduced. It is pointed out that the trend of high-voltage electric power equipment maintenance is so called condition-based maintenance. With the development of computer technology and sensors, on-line monitoring of high-voltage electric power equipment has developed rapidly. By introducing the main principle of Schering bridge to measure tanδ, the way of on-line monitoring of high-voltage electric power equipment was explained. Difference methods of on-line monitoring of insulation parameters for 35 kV substation were discussed. Finally, the shortcomings as well as its tendency of on-line monitoring were analyzed.展开更多
A monitoring and comparison experiment with two types of sensors on a turbojet engine is carried out. Compared with a probe-typed sensor,which is designed successfully before,signals are collected to verify the validi...A monitoring and comparison experiment with two types of sensors on a turbojet engine is carried out. Compared with a probe-typed sensor,which is designed successfully before,signals are collected to verify the validity and better feasibility of the circular sensor.According to the signals monitored over 131h,the typical signals of 125—129 phases are analyzed.The results show that the unusual exhaust particles are carbon depositions from fuel spray nozzle.Therefore,with the electrostatic sensor,early warning can be provided for initial fault condition, as well as real-time reference for the condition-based maintenance.展开更多
The volume of rail traffic was increased by 5 % from 2006 to 2010, in Sweden, due to increased goods and passenger traffic. This increased traffic, in turn, has led to a more rapid degradation of the railway track, wh...The volume of rail traffic was increased by 5 % from 2006 to 2010, in Sweden, due to increased goods and passenger traffic. This increased traffic, in turn, has led to a more rapid degradation of the railway track, which has resulted in higher maintenance costs. In general, degradation affects comfort, safety, and track quality, as well as, reliability, availability, speed, and overall railway performance. This case study investigated the needs of railway stakeholders responsible for analysing the track state and what information is necessary to make good maintenance decisions. The goal is to improve the railway track per- formance by ensuring increased availability, reliability, and safety, along with a decreased maintenance cost. Inter- views of eight experts were undertaken to learn of general areas in need of improvement, and a quantitative analysis of condition monitoring data was conducted to find more specific information. The results show that by implement- ing a long-term maintenance strategy and by conducting preventive maintenance actions maintenance costs would be reduced. In addition to that, problems with measured data, missing data, and incorrect location data resulted in increased and unnecessary maintenance tasks. The conclusions show that proactive solutions are needed to reach the desired goals of improved safety, improved availability, and improved reliability. This also includes thedevelopment of a visualisation tool and a life cycle cost model for maintenance strategies.展开更多
Offshore platforms are of high strategic importance,whose preventive maintenance is on top priority.Buoyant Leg Storage and Regasification Platforms(BLSRP)are special of its kind as they handle LNG storage and process...Offshore platforms are of high strategic importance,whose preventive maintenance is on top priority.Buoyant Leg Storage and Regasification Platforms(BLSRP)are special of its kind as they handle LNG storage and processing,which are highly hazardous.Implementation of structural health monitoring(SHM)to offshore platforms ensures safe operability and structural integrity.Prospective damages on the offshore platforms under rare events can be readily identified by deploying dense array of sensors.A novel scheme of deploying wireless sensor network is experimentally investigated on an offshore BLSRP,including postulated failure modes that arise from tether failure.Response of the scaled model under wave loads is acquired by both wired and wireless sensors to validate the proposed scheme.Proposed wireless sensor network is used to trigger alert monitoring to communicate the unwarranted response of the deck and buoyant legs under the postulated failure modes.SHM triggers the alert mechanisms on exceedance of the measured data with that of the preset threshold values;alert mechanisms used in the present study include email alert and message pop-up to the validated user accounts.Presented study is a prima facie of SHM application to offshore platforms,successfully demonstrated in lab scale.展开更多
In recent years, more and more manufacturers and operators of fleets of mobile systems have been focusing their efforts on studying and developing condi-tional maintenance, monitoring, and diagnostic strategies to cop...In recent years, more and more manufacturers and operators of fleets of mobile systems have been focusing their efforts on studying and developing condi-tional maintenance, monitoring, and diagnostic strategies to cope with an increasingly competitive, unstable, costly, and unpredictable environment. This paper proposes a case study concerning the application of a novel event management architecture, called EMH^2, to a fleet of trains. This EMH^2 architecture, which applies the holonic paradigm, aims to facilitate the monitoring and diagnosis of a fleet of mobile systems. It is based on a recursive decomposition of cooperative monitoring holons. The definition of a generic event modeling, called SurfEvent, is the second key element of the contribution. EMH^2 has been designed to be applicable to any kind of system or equipment up to fleet level. The edge computing paradigm has been adopted for implementation purpose. The EMH^2 architecture is designed to facilitate asynchronous and progressive onboard and off-board deployments. A real-world application of EMH^2 to a fleet of ten trains cur-rently in use, in collaboration with our industrial partner, Bombardier Transport, is presented. Three key perfor-mances indicators have been estimated by comparing EMH^2 with the current industrial situation. These indi-cators are (1) the number of fleet maintenance visits,(2) the time needed by a maintenance operator to investigate and diagnose, and (3) the time needed by the system to update data regarding the health status and monitoring of trains. Results obtained outperformed industrial expecta-tions. The paper finally discusses feedbacks from experi-ence and limitations of the work.展开更多
基金the National Natural Science Foundation of China(60672164)the National High Technology Research and Development Program of China(863Program)(2006AA04Z427)~~
文摘To provide some feasible condition-based maintenance (CBM) decision making methods for civil aeroengine, firstly, the theory of aeroengine CBM decision making is described. The proportional intensity(PI) model is established based on the reliability and condition monitoring data. According to the model, the decision making methods are proposed for the optimal preventive maintenance(PM) interval and removal. Then, the time on wing (TOW) is predicted by collecting actual data based on the engine age and operating conditions. Finally, an example of a fleet for CF6-80C2 engines is illustrated. It shows that sufficient engine operation data are the key of accurate decision making. Results indicate that the CBM decision making methods are helpful for engineers in airlines to control engine maintenance actions and TOW, thus decreasing risks and maintenance costs.
基金performed within the project ARCWIND-adaptation and implementation of floating wind energy conversion technology for the Atlantic region-which is co-financed by the European Regional Development Fund through the Interreg Atlantic Area Program under contract EAPA 344/2016
文摘The existing maintenance strategies of offshore wind energy are reviewed including the specific aspects of condition-based maintenance, focusing on three primary phases, namely, condition monitoring, fault diagnosis and prognosis, and maintenance optimization. Relevant academic research and industrial applications are identified and summarized. The state of art, capabilities,and constraints of condition-based maintenance are analyzed. The presented research demonstrates that the intelligent-based approach has become a promising solution for condition recognition, and an integrated data platform for offshore wind farms is significant to optimize the maintenance activities.
文摘The development process of high-voltage electric power equipment maintenance was introduced. It is pointed out that the trend of high-voltage electric power equipment maintenance is so called condition-based maintenance. With the development of computer technology and sensors, on-line monitoring of high-voltage electric power equipment has developed rapidly. By introducing the main principle of Schering bridge to measure tanδ, the way of on-line monitoring of high-voltage electric power equipment was explained. Difference methods of on-line monitoring of insulation parameters for 35 kV substation were discussed. Finally, the shortcomings as well as its tendency of on-line monitoring were analyzed.
基金Supported by the National Natural Science Foundation of China(60939003,61079013)the Natural Science Fund Project in Jiangsu Province(BK2011737)the Fundamental Research Funds for the Central Universities(NS2012059)
文摘A monitoring and comparison experiment with two types of sensors on a turbojet engine is carried out. Compared with a probe-typed sensor,which is designed successfully before,signals are collected to verify the validity and better feasibility of the circular sensor.According to the signals monitored over 131h,the typical signals of 125—129 phases are analyzed.The results show that the unusual exhaust particles are carbon depositions from fuel spray nozzle.Therefore,with the electrostatic sensor,early warning can be provided for initial fault condition, as well as real-time reference for the condition-based maintenance.
文摘The volume of rail traffic was increased by 5 % from 2006 to 2010, in Sweden, due to increased goods and passenger traffic. This increased traffic, in turn, has led to a more rapid degradation of the railway track, which has resulted in higher maintenance costs. In general, degradation affects comfort, safety, and track quality, as well as, reliability, availability, speed, and overall railway performance. This case study investigated the needs of railway stakeholders responsible for analysing the track state and what information is necessary to make good maintenance decisions. The goal is to improve the railway track per- formance by ensuring increased availability, reliability, and safety, along with a decreased maintenance cost. Inter- views of eight experts were undertaken to learn of general areas in need of improvement, and a quantitative analysis of condition monitoring data was conducted to find more specific information. The results show that by implement- ing a long-term maintenance strategy and by conducting preventive maintenance actions maintenance costs would be reduced. In addition to that, problems with measured data, missing data, and incorrect location data resulted in increased and unnecessary maintenance tasks. The conclusions show that proactive solutions are needed to reach the desired goals of improved safety, improved availability, and improved reliability. This also includes thedevelopment of a visualisation tool and a life cycle cost model for maintenance strategies.
文摘Offshore platforms are of high strategic importance,whose preventive maintenance is on top priority.Buoyant Leg Storage and Regasification Platforms(BLSRP)are special of its kind as they handle LNG storage and processing,which are highly hazardous.Implementation of structural health monitoring(SHM)to offshore platforms ensures safe operability and structural integrity.Prospective damages on the offshore platforms under rare events can be readily identified by deploying dense array of sensors.A novel scheme of deploying wireless sensor network is experimentally investigated on an offshore BLSRP,including postulated failure modes that arise from tether failure.Response of the scaled model under wave loads is acquired by both wired and wireless sensors to validate the proposed scheme.Proposed wireless sensor network is used to trigger alert monitoring to communicate the unwarranted response of the deck and buoyant legs under the postulated failure modes.SHM triggers the alert mechanisms on exceedance of the measured data with that of the preset threshold values;alert mechanisms used in the present study include email alert and message pop-up to the validated user accounts.Presented study is a prima facie of SHM application to offshore platforms,successfully demonstrated in lab scale.
基金led within the context of a research project whose partners were Bombardier Transport, the Polytechnic University of Hauts-de-France (UPHF) and the French National Center for Scientific Research (CNRS)led with the financial support of the Chadian National Centre for Research (CNRD)
文摘In recent years, more and more manufacturers and operators of fleets of mobile systems have been focusing their efforts on studying and developing condi-tional maintenance, monitoring, and diagnostic strategies to cope with an increasingly competitive, unstable, costly, and unpredictable environment. This paper proposes a case study concerning the application of a novel event management architecture, called EMH^2, to a fleet of trains. This EMH^2 architecture, which applies the holonic paradigm, aims to facilitate the monitoring and diagnosis of a fleet of mobile systems. It is based on a recursive decomposition of cooperative monitoring holons. The definition of a generic event modeling, called SurfEvent, is the second key element of the contribution. EMH^2 has been designed to be applicable to any kind of system or equipment up to fleet level. The edge computing paradigm has been adopted for implementation purpose. The EMH^2 architecture is designed to facilitate asynchronous and progressive onboard and off-board deployments. A real-world application of EMH^2 to a fleet of ten trains cur-rently in use, in collaboration with our industrial partner, Bombardier Transport, is presented. Three key perfor-mances indicators have been estimated by comparing EMH^2 with the current industrial situation. These indi-cators are (1) the number of fleet maintenance visits,(2) the time needed by a maintenance operator to investigate and diagnose, and (3) the time needed by the system to update data regarding the health status and monitoring of trains. Results obtained outperformed industrial expecta-tions. The paper finally discusses feedbacks from experi-ence and limitations of the work.