scholarly journals Reliability Importance Measures considering Performance and Costs of Mechanical Hydraulic System for Hydraulic Excavators

2022 ◽  
Vol 2022 ◽  
pp. 1-13
Author(s):  
Wenting Liu ◽  
Qingliang Zeng ◽  
Lirong Wan ◽  
Jinxia Liu ◽  
Hanzheng Dai
Keyword(s):  
Hydraulic System ◽  
High Reliability ◽  
Weighting Factor ◽  
Design Stage ◽  
Failure Data ◽  
Component Identification ◽  
Recovery System ◽  
Mechanical Products ◽  
Hydraulic Excavators ◽  
Maintenance Policies

Although some reliability importance measures and maintenance policies for mechanical products exist in literature, they are rarely investigated with reference to weakest component identification in the design stage and preventive maintenance interval during the life cycle. This paper is mainly study reliability importance measures considering performance and costs (RIMPC) of maintenance and downtime of the mechanical hydraulic system (MHS) for hydraulic excavators (HE) with energy regeneration and recovery system (ERRS) and suggests the scheduled maintenance interval for key components and the system itself based on the reliability R i t . In the research, the required failure data for reliability analysis is collected from maintenance crews and users over three years of a certain type of hydraulic excavators. Minitab is used for probable distribution estimation of the mechanical hydraulic system failure times, and the model is verified to obey Weibull distribution. RIMPC is calculated by multiplying the reliability R i t and weighting factor W i and then compared with other classical importance measures. The purpose of this paper is to identify the weakest component for MHS in the design stage and to make appropriate maintenance strategies which help to maintain a high reliability level for MHS. The proposed method also provides the scientific maintenance suggestion for improving the MHS reliability of the HE reasonably, which is efficient, profitable, and organized.

Analysis of Machine Tool Failures Using Advanced Reliability Models for Complex Repairable Systems

2008 ◽  
Author(s):  
Marco Mazzola ◽  
Angelo Merlo ◽  
Francesco Aggogeri
Keyword(s):  
Machine Tool ◽  
Customer Service ◽  
High Reliability ◽  
Repairable Systems ◽  
Reliability Models ◽  
Failure Data ◽  
Innovative Products ◽  
Maintenance Policies ◽  
Maintainability Analysis ◽  
Non Homogeneous Poisson Process

The competitiveness of modern markets has induced machine tool producers to realize high reliability innovative products. Nowadays, machine tool is an integration of extremely advanced technological devices able to perform tasks with high accuracy and flexibility. The main goal must be to guarantee specified performances, but, above all, to maintain them for all the life cycle time. Reliability and maintainability analysis (R&M) of a complex system deals with many opportunities both for the producers and the customers. The analysis permits to understand the behavior of the machine and to obtain useful information in order to base maintenance policies on analytical results. In this paper a structured R&M analysis for repairable systems is applied to a set of lathes. Failure data are collected by the company customer service for thirty months. The whole system is decomposed into main groups and components. Life data analysis is applied and the failure distribution of the repairable groups is described through a non-homogeneous Poisson process. When complex repairable systems are considered, the reliability must be modeled taking into account that it is strictly influenced by maintenance actions that restore/renew system components when they fail. Finally an R&M perspective for the entire machine is shown.

Overview and Optimized Design for Energy Recovery Patents Applied to Hydraulic Systems

2019 ◽  
pp. 256-285
Author(s):  
Marwa Elhajj ◽  
Rafic Younes ◽  
Sebastien Charles
Keyword(s):  
Energy Saving ◽  
Energy Recovery ◽  
Optimization Technique ◽  
Hydraulic Systems ◽  
Energy Recovery System ◽  
Construction Machinery ◽  
Recovery System ◽  
Hydraulic Excavators ◽  
Complete Study ◽  
Low Efficiency

Due to their large application quantities with extremely low efficiency, pollutant emissions, high fuel consumption, and oil price, researches on the environment protection and the energy saving of construction machinery, especially hydraulic excavators, become very necessary and urgent. In this chapter, the authors proposed a complete study for the excavators' hydraulic energy recovery systems. This study is divided into two parts. In the first one, an overview for the energy saving principles is discussed and classed based on the type of the energy recovered. In the second part and once the energy recovery system is selected, the authors proposed a new approach to design the energy recovery system under a typical working cycle. This approach, the global optimization method for parameter identification (GOMPI), uses an optimization technique coupled with the simulated model on simulation software. Finally, results concluded that applying GOMPI model was an efficient solution as it proves its accuracy and efficiency to design any energy recovery patent applied to hydraulic systems.

scholarly journals Reliability and Lifetime Assessment of Glider Wing’s Composite Spar through Accelerated Fatigue Life Testing

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2310 ◽  
Author(s):  
Sebastian Marian Zaharia ◽  
Mihai Alin Pop ◽  
Răzvan Udroiu
Keyword(s):  
Sandwich Structures ◽  
High Reliability ◽  
Statistical Processing ◽  
Bending Test ◽  
Design Stage ◽  
Test Time ◽  
Glass Fiber Reinforced Plastic ◽  
Reliability Indicators ◽  
Inverse Power Law ◽  
Number Of Cycles

The evaluation of the reliability and the lifetime of aerospace components has become an important segment of the design stage. The aeronautical components are subjected to complex, rigorous tests and have a long test life. The main goal in the field of aviation is to have components with high reliability and quality and to meet the mandatory requirements and regulations. The spars are stiffening components positioned along the wing and which take up most of the load and are tested for fatigue over a long period of time. The spar which was analysed in this study has a sandwich structure with GFRP (glass fiber reinforced plastic) skin and foam core. In this paper, the performances in the static and dynamic conditions of the GFRP-foam sandwich structures cut out of the composite spar of a glider were analysed. Additionally, using accelerated techniques based on the three-point fatigue bending test, the main reliability indicators of the GFRP-foam sandwich structures were determined. Using the statistical processing of the experimental data and the Inverse Power Law–Weibull acceleration model, the mean number of cycles to failure, in normal testing conditions of the GFRP-foam specimens was determined, with a value of 102,814. Using the accelerated testing techniques of the GFRP-foam sandwich structures an important decrease of the test time (8.43 times) was obtained.

scholarly journals Research on a new energy-recovery system for hybrid hydraulic excavators

2019 ◽  
Vol 300 ◽  
pp. 042003
Author(s):  
Daqing Zhang ◽  
Jun Gong ◽  
Yuming Zhao ◽  
Changsheng Liu ◽  
Peng Hu ◽  
...  
Keyword(s):  
Energy Recovery ◽  
Energy Recovery System ◽  
Recovery System ◽  
New Energy ◽  
Hydraulic Excavators

Synthetic Reliability Assessment Model involving Temperature–Humidity Step-Stress Based on Wiener Process

2020 ◽  
pp. 2150016
Author(s):  
Bin Suo ◽  
Liang Zhao
Keyword(s):  
Wiener Process ◽  
High Reliability ◽  
Likelihood Estimation ◽  
Degradation Process ◽  
Test Sample ◽  
Assessment Model ◽  
Engineering Practice ◽  
Accelerated Degradation ◽  
Failure Data ◽  
Newton Iteration Method

There are always some difficulties in storage reliability evaluation of high-reliability, long-life, and high-value products, such as the test sample being small, degradation speed being slow, and failure data being inadequate. Temperature–humidity step-stress accelerated degradation test (THSS-ADT) is an effective method to evaluate the reliability of this type of products, but the test data processing is an extremely complex work. The motivation of this paper is to provide a clear, effective, and convenient method to evaluate the reliability on the basis of THSS-ADT data. Considering the stochastic volatility in degradation process, Wiener process is used to modeling the accelerated degradation process. The methods to estimate the parameters of Peck accelerated model and degradation model are discussed under temperature–humidity step-stress. As ordinary optimization algorithms (such as Newton Iteration Method and impelling function method) find it difficult to get the solutions, particle swarm optimization (PSO) method is used to solve the problem of maximum-likelihood estimation. Finally, the proposed methods are demonstrated for two examples, in which one is a numerical simulation, and another is an engineering practice of a microwave power amplifier.

1.2 Computers and Their Potential: Software

1981 ◽  
Vol 5 ◽  
pp. 5-8
Author(s):  
Pamela A. Geisler ◽  
J. France
Keyword(s):  
High Reliability ◽  
Computer Hardware ◽  
Design Stage ◽  
Final Phase ◽  
Implementation Phase ◽  
Storage Media ◽  
Systems Software ◽  
And Performance ◽  
High Level

At the present time, with the high reliability and performance of computer hardware, computer systems applied in any field must be judged more by the quality of the software provided. Thus it is highly relevant in an investigation of the use of computers in a field such as animal production, to concentrate on aspects of the software.Software provides the computer with the ability to obey instructions and to do as the user wishes. However, before arriving at these ‘machine instructions’ a number of steps have to be covered. First, it is essential to design the software — that is, to establish the requirements to be achieved on the computer. This design stage is followed by the implementation phase, in which the requirements as stated in English are transformed into such instructions as the machine can read and obey. The final phase is testing, in which it must be determined whether the requirements have been met, and to modify the design and iterate until the performance is satisfactory.Software in general can be divided into three classes — systems, utility and applications software. The systems software drives the machine and its associated peripherals such as a VDU and printer. The systems software also includes a file system for organization of the data on the relevant storage media (floppy disks, cartridges, magnetic tape). Also considered part of the systems software are the assembler, interpreters and compilers for high level languages such as BASIC and FORTRAN and for programming aids such as DEBUGGERS. Systems software is normally supplied with the computer and needs to be evaluated along with the hardware by any prospective purchaser of a computer system.

Hydraulic actuation of multi-body structures through large-scale motions. Part 2: Controller design and performance

2008 ◽  
Vol 222 (3) ◽  
pp. 365-375
Author(s):  
D T Branson ◽  
P S Keogh ◽  
D G Tilley
Keyword(s):  
Hydraulic System ◽  
Large Scale ◽  
Controller Design ◽  
Experimental Tests ◽  
Companion Paper ◽  
Design Stage ◽  
Base Level ◽  
Active Vibration ◽  
And Performance ◽  
Multi Body

This paper addresses a controller design methodology for the hydraulic actuation of non-linear multi-body systems. It takes account of system uncertainties, envisaged system changes through added mass, positioning speed requirements, and vibration control. A mathematical model developed in the companion paper, Part 1, describes an experimental multi-body structure that is actuated by a hydraulic system. It is used to generate H∞-based position and active vibration controllers to meet the actuation requirements at the design stage. Experimental tests were undertaken with the developed H∞ controllers to demonstrate their accuracy and stability of motion control. The results are compared to ‘base level’ tests completed using a more traditional proportional-integral (PI) controller. In contrast with the instability experienced using PI control, the design process associated with the H∞ controllers ensures accurate closed loop stability over the range of system variations.

The Design of Plate Mills Hydraulic Lubricating and Monitoring System

2014 ◽  
Vol 1006-1007 ◽  
pp. 643-649
Author(s):  
Zhi Qiang Wu ◽  
Jun Fang Zhao
Keyword(s):  
Monitoring System ◽  
Temperature Control ◽  
Hydraulic System ◽  
High Reliability ◽  
Working Time ◽  
Central Control ◽  
High Grade ◽  
Hydraulic Station ◽  
Signal Complexity

Plate mills hydraulic system is made up of several hydraulic stations, lubrication stations and grease stations, these hydraulic stations and lubrication stations are distributed around the mills. Each hydraulic station possesses qualities of successive long working time, high reliability and signal complexity, and it can satisfy diverse demands of high grade pressure or temperature control, etc. This paper is based on these demands, assembling control missions of hydraulic and lubricating stations. Several PLC S7-300 were chosen to match the need of controlling mills hydraulic and lubricating system for a certain plate factory, and the HMI monitoring system for mill hydraulic and lubricating stations was developed by WINCC, which achieved central control and monitoring the hydraulic and lubricating system of plate mills.

A Review of Reliability Principles in Conceptual Design

2011 ◽  
Vol 199-200 ◽  
pp. 583-586
Author(s):  
Yu Lian Cui ◽  
Wei Wu
Keyword(s):  
Conceptual Design ◽  
High Reliability ◽  
Reliability Prediction ◽  
Design Stage ◽  
Design Phase ◽  
Product Reliability ◽  
Design Decisions ◽  
Early Stages ◽  
Conceptual Design Phase

In this paper an attempt has been made to identify certain useful parts that will assist to consider reliability during conceptual design phase. The aim is to provide some thoughts and a toolkit for addressing reliability during the early stages of design, influencing design decisions and product reliability, and reducing the relying on the reliability prediction and expensive experiments in later design stage. Therefore high reliability can be cost-effectively achieved.

The Numerical Control Device Reliability Based on Bayesian Approach

2014 ◽  
Vol 556-562 ◽  
pp. 2515-2518
Author(s):  
Bin Quan Li
Keyword(s):  
Material Selection ◽  
High Reliability ◽  
Reliability Evaluation ◽  
Control Device ◽  
Numerical Control ◽  
Mcmc Method ◽  
Failure Data ◽  
Device Reliability ◽  
Important Means ◽  
Complex Forms

The material selection and manufacturing processes of numerical control device were related with the reliability of system. Therefore, the reliability evaluation of it was significant. Numerical control system was, obviously, high-reliability product and the application of Bayesian theory has become an important means of its reliability assessment. The failure data of numerical control device obeys Weibull distribution which has complex forms. The posterior distribution becomes extremely complicated and the numerical integration which Bayesian computing depends on is not available. Markov chain Monte Carlo (MCMC) method ensures the implementation of the assessment. The result of Bayesian estimation proves that it increases the robustness, accuracy and effectiveness of the calculation and it's suitable for numerical control device reliability evaluation.

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