Queueing
Sections
Topics
Five sections, in rotation. A piece belongs to one of them, which forces a decision about what it actually is before a word of it is written.
Fundamentals
6 pieces
The ideas the rest of it is built on, worked properly rather than defined and left there.
Constraints
We fixed the bottleneck and the output barely moved
Measurement
We have no data. Where do we start?
Root cause
The five whys finds one cause, and most delays do not have one
Constraints
We added two people and nothing came out any faster
Constraints
Most constraints get elevated before they are ever exploited
Metrics and maths
8 pieces
The measures that get quoted in meetings, what each one actually counts, and the arithmetic behind them.
Measurement
You have the cycle times. Now what does the picture mean?
Queueing
How long will this backlog take to clear? There is an equation for that
Quality
A ten percent rework rate is not a ten percent problem
Variation
The average was met and a quarter of the orders were late
Bottlenecks
The hour you lost at the bottleneck did not cost forty five dollars
Utilization
The last ten percent of utilization costs more than the first eighty
Queueing
Little's Law does not care what the board says
Measurement
Cycle time and lead time are not the same number
Lean tools
6 pieces
Shop floor method: what each tool is for, and the conditions it needs to work at all.
Line balance
Our demand swings by half. Does takt time still apply?
Batching
Most of your changeover happens while the machine is stopped for no reason
Flow
Moving to pull does not remove the inventory. It shows you where it was.
Standard work
You cannot automate a step that is done five different ways
Batching
A batch size is a changeover time that nobody measured
Line balance
Takt time is a demand number, not a target
Case walkthroughs
2 pieces
One process, followed end to end, with every number shown along the way.
Process mapping
Ninety seven percent of that form's life is waiting
Process mapping
The boxes on a process map are not where the time goes
Simulation and what if
3 pieces
Asking a question about a process before changing it, and knowing what the answer is worth.