Abstract
Gamma distribution is known as the most suitable distribution to model the monotonically increasing wear or deterioration. Examples of wear or deterioration can be found in many of the mechanical components, such as in wear of the bearings, corrosion or erosion wear of pump casings and impellers etc. The component wearing gradually can be considered to have failed when it reaches a pre-specified, optimal wear limit. Calculation of MTTF (mean time to failure or to reach a wear or deterioration limit) is however cumbersome and time consuming as it has to be integrated numerically. The author presents an approximation formula to calculate the MTTF for a gamma wear process with temporal variability which can be easily applied to most of the mechanical components undergoing wear. Error in calculation of MTTF using the theoretical and the approximation formula have been displayed in a graphical form as a ratio of the theoretical MTTF.
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Verma, A.K., Srividya, A. & Rana, A. Approximation of MTTF calculation of a non-stationary gamma wear process. Int J Syst Assur Eng Manag 2, 282–285 (2011). https://doi.org/10.1007/s13198-011-0079-0
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DOI: https://doi.org/10.1007/s13198-011-0079-0