Cost of Corrosion Key Performance Indicator

N is estimated number of replacement cycles to end of service life 

however, the calculated remaining life of a component (RL J as defined in Eq. (12.4) is greater than the field life (FL), can be assumed to be zero. This is based on the assumption that the KPI is a performance indicator reflecting the effect on operating costs (Opex) and does not consider depreciation against the initial capital cost (Capex). The number of replacement cycles (N ) can be estimated with Eq. (12.3)  

The above formulae have been developed from an actual pipework monitoring and replacement program as a result of internal corrosion effects. Both replacement cost R J, component remaining life (RL and field life (FL) are key factors in this method and reflect the need to understand accurate costing of installation and replacement activities. Required field life is not necessarily the difference between installation and design lives but more appropriately the time remaining until end of field or production life. 

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