Reliable Housing Research Articles

A hazard analysis of heavy CNC machine tools based on fusion fault correlation

AbstractThis paper presents an analysis of the fault correlation between CNC machine tool subsystems using decision laboratory analysis and the House of Reliability (HoR) methodology. Initially, the maintenance information of the machine tool and other hazard indicators is comprehensively analyzed based on the cognitive best worst method (CBWM) to assign weights of hazard indicators. The HoR method is then employed to perform fault correlation fusion, which results in comprehensive hazard analysis results of the machine tool subsystems considering the fault correlation. Finally, the results obtained from the fusion fault correlation and the traditional hazard analysis are compared. The results indicate that the proposed method can highlight the relatively important subsystems and the most vulnerable parts of the machine tools. Overall, the hazard analysis results of this paper contribute to the safe and reliable operational and maintenance optimization of CNC machine tools.

Fault correlation analysis-based framework for reliability deployment of electromechanical system

Reliability allocation is a very critical step of product development process for setting achievable reliability goals. However, most research on reliability allocation have ignored the correlation between faults in a complex electromechanical system. In view of this problem, this work proposed an optimizationmethod of reliability allocation by combining Quality Function Deployment (QFD) and Failure Tree Analysis (FTA). First, a fault tree of the system is build, and failure mode of the system is discovered in the bottom events of the fault tree. Second, the failure mode in previous step is input into House of Reliability (HoR), and the correlation of faults and fault severity could be calculated in the HoR. Finally, according to the results of HoR, the fault severity of each component is transformed into the importance degree, and the system reliability target is allocated to each component on the basis of the importance degree. A case study of a transmission agent was conducted to illustrate the analysis and application processes of the proposed method. The result showed that this method made the distribution more reasonable by considered the correlation between failures.

Reliability prediction of electromechanical system concerned about correlation of multiple failures based on RFD

As the boosting complexity of developing electromechanical system in various fields, significant efforts have been recently devoted to the reliability analysis of electromechanical system to obtain better precision of reliability prediction, leading to advanced demand of reliability predictionmethodologies. Conventional system reliability prediction adopts the reliability prediction theory of electronic products which ignores the interaction among different components. Aiming at this, an improved reliability calculation approach concerning correlation is proposed in this paper, taking dependence into account by considering the correlation degree between the primary and the secondary failure modes of components as the main factor in reliability prediction by building failure modes reliability prediction HOR (house of reliability) of components.

Failure Mode and Effects Analysis by Using the House of Reliability-Based Rough VIKOR Approach

Failure mode and effects analysis (FMEA) is a widely used reliability analysis tool for identifying and eliminating known or potential failures in system, design, and process. In traditional FMEA, failure modes are evaluated by FMEA team members with respect to three risk factors: severity (S), occurrence (O), and detectability (D), and ranked via their risk priority number (RPN), which is obtained by multiplying the crisp values of S, O, and D. However, traditional RPN has been considerably criticized due to the following shortcomings: not considering the different weights of risk factors; the identical value of RPN for different combinations of S, O, and D; the diversity and uncertainty of evaluation information given by FMEA team members and without considering the dependence among different failure modes. Although significant efforts have been made in FMEA literatures to overcome these shortcomings, there are still some deficiencies. In this paper, a new risk priority model is presented for FMEA by using the house of reliability (HoR)-based rough VIsekriterijumska optimizacija i KOmpromisno Resenje (VIKOR) approach. In the proposed model, the HoR is introduced to identify the dependence among different failure modes and the link between failure modes and the risk factors of O, D and the subcriteria of S. Rough number is introduced to manipulate the subjectivity and vagueness in decision making and VIKOR approach is used to determine the risk priority order of failure modes in a comprehensive way. Finally, an illustrative case in transmission system of a vertical machining center has demonstrated the effectiveness and practicality of the proposed model.

The house of reliability

PurposeThe purpose of this paper is to provide a structured methodology for performing build‐in reliability (BIR) investigation during a new product development cycle.Design/methodology/approachThe methodology in this paper represents an extension of the Quality Functional Deployment/House of Quality (QFD/HoQ) concepts to reliability studies. It is able to translate the reliability requisites of customers into functional requirements for the product in a structured manner based on a Failure Mode And Effect Analysis (FMEA). Besides, it then allows it to build a completely new operative tool, named House of Reliability (HoR), that enhances standard analyses, introducing the most significant correlations among failure modes. Using the results from HoR, a cost‐worth analysis can be easily performed, making it possible to analyse and to evaluate the economical consequences of a failure.FindingsThe paper finds that the application of the proposed approach allows users to identify and control the design requisites affecting reliability. The methodology enhances the reliability analysis introducing and managing the correlations among failure modes, splitting the severity into a detailed series of basic severity aspects, performing also cost/worth assessments.Practical implicationsIt is shown that the methodology enables users to finely analyse failure modes by splitting severity according to the product typology and the importance of each Severity criterion according to laws or international standards. Moreover the methodology is able to consider the “domino effects” and so to estimate the impact of the correlation between the causes of failure. Finally a cost/worth analysis evaluates the economical consequences of a failure with respect to the incurred costs to improve the final reliability level of the product.Originality/valueThe paper proposes a completely new approach, robust, structured and useful in practice, for reliability analysis. The methodology, within an integrated approach, overcomes some of the largely known limits of standard FMECA: it takes into account multiple criteria, differently weighted, it analyses the product considering not only the direct consequence of a failure, but also the reaction chain originated by a starting failure.