Introduction

Maintenance can either be time based or condition based, depending on the service strategy selected. The time based maintenance is carried out at predetermined intervals of time or on the base of prescribed criteria and aimed at reducing the probability of failure or the working deterioration of the element.

In the condition based maintenance the asset condition is monitored and performance degradation is tracked. Risk-based (based on asset and risk assessment) and condition-based (based on either on-site or remote monitoring) maintenance strategies may be applied. Maintenance based on the control of the performances of an element and/or the main parameters for its operation and based on the control of the corrective actions consequently taken.

Both strategies can be of a preventive character, consisting of regular inspections, regular maintenance (like retightening of gaskets) and pre-defined component replacements (like bushings).