Life cycle maintenance costs for a non-exponential component

•Maintenance Costs (Repairs & Spares) for non exponential items based on item’s Reliability model.•Calculations by application of trapezoidal rule, controlled accuracy.•Universal for any Reliability Model (as opposed to currently used analytic models).•Long term Life cycle prediction (as opposed to currently used Field Failure observation methods).•Solved by simple tools (Excel sheet) as opposed to complex Monte Carlo simulation tools. The paper presents a method for determining maintenance and spare provisioning costs, for systems containing a non exponential component. The input data of the model are R(t) - the reliability function with time of the component, T the duration of the life cycle, cost of a repair, cost of a spare part and the turnaround time. The model is applicable for any form of R(t): Weibull, Normal, expressed by an explicit or implicit set of equations and even in the form of discrete frequency table. The calculations can be performed by a simple Excel worksheet and do not require expensive tools (e.g. a flexible Monte Carlo package): The algorithm requires a few iterations of the dot product of two matrices. The entries of the matrices are calculated from the input values and the results of previous iterations, at M equidistant time points along the life cycle. M determines the accuracy of the calculations. The paper indicates sufficient conditions for M, which ensure a desired accuracy. Numerical examples performed on an Excel worksheet are presented. Since the model is applicable for any R(t), it was applied, for verification purposes for R(t)=e−λt, which has well known accurate results. The comparison confirmed the accuracy of the approximations.