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Reliability, Maintainability, and Availability Analysis of a Computerized Numerical Control Machine Tool Using Markov Chains

Authors:
Rajkumar Bhimgonda Patil at Pimpri Chinchwad College Of Engineering
Rajkumar Bhimgonda Patil
Mohamed Arezki Mellal
Mohamed Arezki Mellal
Anand Bewoor at Cummins College of Engineering for Women
Anand Bewoor
Sameer Al-Dahidi at German Jordanian University
Sameer Al-Dahidi
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Reliability, maintainability, and availability analysis of Computerized Numerical Control Machine Tools (CNCMT) is vital as they are widely used in manufacturing industries for mass production. This paper proposes a generalized framework for Time-Between-Failure (TBF) and Time-To-Repair (TTR) data analysis, integrated with Markov chains for estimating the system's Steady State Availability (SSA). A case study of a typical CNCMT illustrates the applicability and the effectiveness of the proposed framework. The effect of variation of sub-systems' failure and repair rates on the availability of the CNCMT is studied. The critical subsystems from reliability, maintainability, and availability point of view are identified. The analysis reveals that the CNCMT's failure and repair rates are nearly constant and the CNCMT fails four times per year. The Lubrication Subsystem (LS) is the utmost severe subsystem as far as maintainability aspect is concerned and Turret Subsystem (TS) is the utmost severe subsystem from a reliability perspective.
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Article
Full-text available
  • Sep 2017
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Full-text available
  • Jan 2015
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A two-level Bayesian early fault detection for mechanical equipment subject to dependent failure modes
Article
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Bayesian method to solve the early failure period of numerical control machine tool
Article
  • Oct 2016
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