Balancing the Line
Balance a multi-station line so no single station dominates — including the SECOND bottleneck that appears once you fix the first — to hit a high throughput target.
Try this first — before any explanation.
This four-station line runs at 6/min; the target is 12/min. Fix the obvious bottleneck and a new one immediately takes its place. Balance the line so every station can keep up.
Edit the production line (JSON: each station has a cycle time in seconds and a number of parallel machines), then run it. The twin animates parts flowing and grades the line's throughput.
Balancing the Line
Edit the production line (JSON: each station has a cycle time in seconds and a number of parallel machines), then run it. The twin animates parts flowing and grades the line's throughput.
The idea, built visually.
Fix the slowest station and you don't win — you just promote the second-slowest to bottleneck. To hit a target rate, every station has to clear the same bar: the required cycle, which is sixty divided by the target. Twelve a minute means five seconds a part, everywhere. Any station slower than five — per machine — needs more machines until it drops under the bar. Balancing isn't speeding up one thing; it's getting the whole line under the same ceiling.
▣ Stage animation: Four stations; the tall 'Drill' bar gets halved (×2) and the readout jumps — then 'Test' lights up as the new bottleneck; a dashed 'required cycle = 5s' line drops across all bars, and machines are added until every bar sits under it, readout locking at 12/min.
Build it up, step by step.
1. Required cycle. target 12/min → 60/12 = 5 s/part ceiling for every station. 2. Who's over? Drill 10/1 = 10 and Test 8/1 = 8 both exceed 5; Cut and Assemble (5) are fine. 3. Add machines until under the ceiling. Drill ×2 = 5, Test ×2 = 4. Now the max per-machine cycle is 5 → 12/min.
How the Bench grades your run.
PASS WHEN PASS when EVERY station's per-machine cycle is ≤ the required cycle (5 s) so the line sustains 12/min.
- You fixed one station but the SECOND-slowest is now the bottleneck — bring it under 5 s/part too.
- Required cycle for 12/min is 60/12 = 5 s/part; any station above that (per machine) caps the line.
- Over-built — you added machines to a station already under 5 s/part; not wrong for throughput, but wasteful (see the next lesson).
Bring back what you've already mastered.
- Required cycle for a target rate R/min = ____ (60 ÷ R).
- After you fix the bottleneck, the new limit is the ____-slowest station (second).
- A balanced line has every station at roughly the ____ per-machine cycle (same).
What you must demonstrate to advance.
Balance every station under the required cycle so the line sustains the target rate.
How this feeds your build.
Line balancing + bottleneck analysis combine in the factory capstone.