OPS.15.1:5.2 - One batch, several parts, one machine

A machine processes three parts together from minute zero to thirty. The completion event is linked to all three parts. The machine is otherwise available throughout a sixty-minute observation window.

The batch occupies thirty machine-minutes: utilization under this occupied-time definition is 30/60. The parts accumulate ninety part-minutes of batch residence. Copying the cycle interval into three part records preserves each part’s history but does not create ninety machine-minutes.

Part 2 requires another ten-minute cycle from minute forty to fifty. Machine occupation becomes forty minutes and utilization 40/60. There are three distinct parts and four processing visits. The returned part’s additional visit consumes capacity while its customer-level completion follows the acceptance rule.

If an operator attends only loading and unloading, machine occupation does not establish operator attention time. Recover those intervals before making a staffing claim.