Fault tree analysis of a hydraulic system based on the interval model using latin hypercube sampling

A hydraulic system is a key subsystem of heavy-duty machine tools with a high failure intensity, the failure of which often causes shutdown of production and economic loss in machining. Therefore, it is necessary to implement failure analysis to identify the weak links of system and improve the reliability. For hydraulic system, there is often an amount of failure data collected in field, which help to calculate the occurrence probability of basic events through fault tree analysis method. However, the data are incomplete and uncertain. To address this issue, this study presents a fault tree analysis methodology. Experts’ opinions are utilized, combined with field data based on the Dempster–Shafer theory and rough set theory to fill the incompleteness and eliminate the uncertainty. For application in a case study, a fault tree of the hydraulic system of heavy-duty machine tools is firstly constructed. Then, the importance analysis is performed to help identify the weak links of hydraulic system. The results show the critical basic events affecting the safety and reliability of a hydraulic system.

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Fault Diagnosis to Mid-Size Excavator Hydraulic System Based on Fault Tree Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.44-47.1110 ◽

2010 ◽

Vol 44-47 ◽

pp. 1110-1114

Author(s):

Chi Ma ◽

Ke She Wang ◽

Jiang Hong Sun

Keyword(s):

Hydraulic System ◽

Fault Tree ◽

Fault Tree Analysis ◽

System Structure ◽

Qualitative And Quantitative Analysis ◽

Logical Relationship ◽

Tree Analysis ◽

Qualitative And Quantitative ◽

Weakest Link ◽

Relationship Of

Analyzes slewing hydraulic system of hydraulic excavator by fault tree analysis. According to logical relationship of slewing hydraulic system structure, draws fault tree. Finishes qualitative and quantitative analysis. Divides the minimum cut sets. Calculates the reliability of the whole system in order to find the weakest link. Puts forward ways to increase the reliability.

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Safety Assessment hydraulic system Aircraft H-8

Angkasa: Jurnal Ilmiah Bidang Teknologi ◽

10.28989/angkasa.v9i2.186 ◽

2017 ◽

Vol 9 (2) ◽

pp. 39

Author(s):

Cyrilus Sukoco Budiono

Keyword(s):

Hydraulic System ◽

Safety Assessment ◽

Fault Tree ◽

Fault Tree Analysis ◽

Assessment Process ◽

System Safety ◽

Markov Analysis ◽

Tree Analysis ◽

Failure Conditions ◽

Secondary Power

Safety Assessment hydraulic system Aircraft H-8AbstrakSistem hidrolik termasuk secondary power yang digunakan untuk menggerakkan bidang atur kendali terbang, mengeluarkan dan melipat roda pendarat, dan memberikan tenaga pengereman ketika pesawat di darat. Kegagalan sistem hidrolik dapat menyebabkan pesawat hilang kendali sehingga memungkinkan pesawat mengalami kecelakaan dan jatuhnya korban jiwa. Penelitian ini membahas tentang penilaian keselamatan sistem hidrolik pesawat terbang H-8 yang mencakup proses penilaian keselamatan, regulasi mengenai sistem hidrolik pesawat terbang, beban-beban yang harus ditanggung oleh sistem hidrolik, dan prestasi sistem hidrolik pesawat H-8. Penilaian keselamatan dimulai dari melakukan identifikasi fungsi, kondisi kegagalan, efek kegagalan, dan mengklasifikasikan kondisi kegagalan dari sistem hidrolik tersebut.Kata kunci : System Safety Assessment (SSA), sistem hidrolik, Fault Tree Analysis (FTA), Markov Analysis (MA), Fanctional Hazard Asessment (FHA). Abstract A hydraulic system is one of the secondary power used to drive the flight control surfaces, retract and extend landing gears, and to provide power to wheel brakes when the aircraft is on the ground. The failure of the hydraulic system results in aircraft lost of control which can lead to aircraft accident and passenger deaths. This journals discusses the safety assessment of the hydraulic system to be used in H-8 aircraft which includes the safety assessment process, regulations of the aircraft hydraulic system, the hydraulic system loads, and the aircraft hydraulic systems performance. The safety assessment begins with identification and classification of the functions, failure conditions, the effects of failure, and classify the failure conditions of the hydraulic system.Key word : System Safety Assessment (SSA), hydraulic system, Fault Tree Analysis (FTA), Markov Analysis (MA), Fanctional Hazard Asessment (FHA).

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Fuzzy Dynamic Fault Tree Analysis of Hydraulic System of CNC Machining Center

Volume 7: 5th International Conference on Micro- and Nanosystems; 8th International Conference on Design and Design Education; 21st Reliability, Stress Analysis, and Failure Prevention Conference ◽

10.1115/detc2011-47583 ◽

2011 ◽

Author(s):

Yan-Feng Li ◽

Jian Sun ◽

Haiqing Li ◽

Hong-Zhong Huang ◽

Yu Liu

Keyword(s):

Hydraulic System ◽

Fault Tree ◽

Fault Tree Analysis ◽

Probability Of Failure ◽

Cnc Machining ◽

Extension Principle ◽

Tree Analysis ◽

Dynamic Fault Tree ◽

Machining Center ◽

Cnc Machining Center

Fault tree analysis (FTA), as an effective reliability assessment tool, is a widely used in analyzing the risk and reliability of large scale and complex engineering systems. Dynamic fault tree analysis (DFTA) extends the static fault tree by defining additional gates to model the complicated interactions, and in most case, Markov models can be used to solve dynamic gates. In many real systems, it is quite difficult to evaluate the probability of failure events preciously due to many uncertainty factors. To account for the uncertainty resulting from the lack of sufficient data or the subjective adjustments from experts, a fuzzy dynamic fault tree model is proposed to assess the system reliability when acquiring precious probability of failure event is impossible. With the aim of obtaining the membership function of the fuzzy probability of the top event, the extension principle is employed. The proposed method and algorithm are demonstrated by a case study of the hydraulic system of a specific CNC machining center.

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Fault Diagnosis to Mid-Size Excavator Bucket Hydraulic System Based on Fault Tree Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.190-191.88 ◽

2012 ◽

Vol 190-191 ◽

pp. 88-92

Author(s):

Jiang Hong Sun ◽

Chi Ma ◽

Yuan Lin Yi

Keyword(s):

Hydraulic System ◽

Fault Tree ◽

Fault Tree Analysis ◽

System Structure ◽

Qualitative And Quantitative Analysis ◽

Logical Relationship ◽

Tree Analysis ◽

Qualitative And Quantitative ◽

Excavator Bucket ◽

Relationship Of

Analyzes bucket hydraulic system of hydraulic excavator by fault tree analysis. According to logical relationship of hydraulic system structure, draws fault tree, finishes qualitative and quantitative analysis .Divides the minimum cut sets. Calculates the reliability of whole system to find the weakest components. Puts forward ways to increase the reliability on basis of oil pipe.

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Hydraulic Fault Diagnosis Expert System of Excavator Based on Fault Tree

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.228-229.439 ◽

2011 ◽

Vol 228-229 ◽

pp. 439-446 ◽

Cited By ~ 1

Author(s):

Guo Ping Li ◽

Qing Wei Zhang

Keyword(s):

Expert System ◽

Hydraulic System ◽

Expert Knowledge ◽

Fault Tree ◽

Fault Tree Analysis ◽

Hydraulic Excavator ◽

Law And Order ◽

Tree Analysis ◽

System Breakdown ◽

Maintenance Personnel

The constituting of diagnosis expert system and the basic theory of fault tree analysis were introduced at first. A model of combining fault tree with expert system was analyzed. It focused on the hydraulic excavator PC220-7 for Komatsu according to the hydraulic system breakdown of law and order was particularity. A method combined the fault tree analysis with an expert system based rules was adopted. It was expressed systematically expert knowledge by building a fault tree. According to the fault tree, a database of diagnostic rule can be automatically generated. Automatic diagnosis knowledge acquisition has become reality. A hydraulic system fault of excavator was given as an example to design an expert system with the function of complex reasoning and explanation. It provides a reference for hydraulic excavator of the use of management and fault maintenance personnel to solve excavator problems. It shows that this method has a good application in the future.

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