Find the bottleneck
Throughput is constrained by the step that cannot keep up with arrivals. Measure effective capacity during the busiest period, allowing for downtime, changeovers and failed work.
Worked example
A dryer processes 12 tonnes per hour for 8 hours. Two hours of cleanout reduce effective throughput to 72 tonnes. If intake is 90 tonnes, the buffer grows by 18 tonnes that day, regardless of annual spare capacity.
Change the assumption
The mill cuts cleanout from two hours to one. Does a 90-tonne intake still create a queue?
Check the reasoning
Seven hours at 12 tonnes per hour yields 84 tonnes. The backlog still grows by 6 tonnes that day. Consider overtime or rescheduling arrivals if quality and staffing permit.
Check your reasoning
What happens if intake rises while dryer capacity is unchanged?
Reveal the explanation
The buffer fills earlier. Add or schedule drying capacity, divert overflow or reschedule receipts before purchasing faster intake equipment.
Try the same framework in a different case
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