The changes in the condition of a plant component are determined with the help of long-term analyses, whereby starting from an optimal condition, this deteriorates over time. In the schematic representation of the condition development over time, the following points are to be emphasized: the point (S) at which the fault or the condition deterioration begins, the point (P) at which the fault can be recognized and the point (F) at which the fault occurs.
Corrective maintenance is only carried out when the fault has occurred, i.e., at the end of the P-F interval. The consequence is a failure of the plant, which causes high costs.
Preventive maintenance implies that maintenance measures are carried out based on predefined maintenance intervals. These intervals can depend on both time and usage and should be shorter than the P-F interval. This maintenance strategy can lead to maintenance being performed too frequently, resulting in unnecessary costs.
Condition-based maintenance is based on continuous monitoring, data analysis and anomaly detection. The intention is to detect the occurrence of faults earlier, thus increasing the P-F interval as the point (P) at which the fault is detected is moved forward in time.
Predictive maintenance uses the entire period of the P-F interval to flexibly schedule the maintenance task. The planning is done for all components at the same time, so that an efficient and cost-effective maintenance plan can be generated.
Fraunhofer Institute for Transportation and Infrastructure Systems IVI