Process Reliability KPIs calculation details (preview)

The values for the different Process Reliability KPIs are derived from a special event type called PREventHourly, available only in selected assets. Process Reliability is similar to OEE, but has two main differences.

• OEE usually excludes planned downtime, while Process Reliability includes it.

• Process Reliability expresses its components as time losses. In OEE, performance and quality are calculated as ratios of production rate and waste, respectively.

Process Reliability (PR)

The value for this KPI is determined by subtracting these Process Reliability KPIs from 100% Process Reliability: Planned Dowtime (PDT), Unplanned Downtime (UPDT), Quality Loss, and Rate Loss. It is calculated using the following expression:

PR(%) = 100% - PDT% - UPDT% - Quality Loss% - Rate Loss%

Planned Downtime (PDT)

PDT% is the percentage of the Total production time spent in a planned downtime state. This KPI is calculated by using the following expression:

PDT(%) = (Planned downtime / Total production time)*100

or

PDT(%) = (Planned downtime / (Actual runtime + Planned downtime + Unplanned downtime + Microstops))*100

Unplanned Downtime (UPDT)

UPDT % is the percentage of the Total production time spent in an unplanned downtime or microstop state. This KPI is calculated by using the following expression:

UPDT (%) = ((Unplanned downtime + Microstops) / (Total production time))*100

or

UPDT (%) = ((Unplanned downtime + Microstops) / (Actual runtime + Planned downtime + Unplanned downtime + Microstops))*100

where:

Total production time is the total time excluding idle time

Actual runtime is the time spent in the running state

Rate Loss

Rate Loss % is the percentage of the Total production time lost by running below target rate. This KPI is calculated by using the following expression:

Rate Loss (%) = ((1- OEE performance)* Actual runtime / Total production time))*100

where:

Total production time is the total time excluding idle time

Actual runtime is the time spent un running state

Quality Loss

Quality Loss % is the percentage of the Total production time lost by producing non-good quality goods. This KPI is calculated based on the following expressions:

Quality Loss (%) = ((1- OEE quality)* Adjusted runtime / Total production time))*100

where:

Total production time is the total time excluding idle time

Adjusted runtime is Actual runtime - Rate Loss (minutes)