VIRTUAL FACTORY

Throughput & the Bottleneck

Find a line's bottleneck — the station with the slowest per-machine cycle — and fix it so the line meets its throughput target.

01Challenge

The line runs at 6.7 parts/min, but the order needs 8/min. Three stations are wired in series; one of them is choking the whole line. Run it, find the bottleneck, and fix only that station.

02Model

A line moves only as fast as its slowest station — the bottleneck. And what counts is per-machine time, not total work: a 9-second station with one machine pushes a part every 9 seconds, but give it a second machine and the two share the load — 4.5 seconds a part. Throughput is just sixty over the bottleneck's cycle. Here's the trap: speed up any OTHER station and nothing changes — the bottleneck still sets the pace. Speed up the bottleneck and the whole line speeds up.

Throughput is capped by the slowest station.

03Guided practice

1. Per-machine cycle. For each station compute time ÷ machines. Cut 4/1=4 s, Drill 9/1=9 s, Assemble 3/1=3 s. 2. Bottleneck = the max. Drill at 9 s/part sets the rate: 60/9 = 6.7/min. 3. Fix it. Give Drill a second machine ("machines": 2) → 9/2 = 4.5 s/part → 60/4.5 = 13.3/min. Run it.

04Feedback

PASS WHEN PASS when the line throughput ≥ 8 parts/min — i.e. the bottleneck's per-machine cycle is fast enough.

Still under 8/min — the bottleneck is the station with the highest time ÷ machines. Add a machine THERE (Drill), not elsewhere.
You sped up a non-bottleneck — throughput didn't budge. Only the slowest per-machine station sets the rate.
Throughput = 60 ÷ (bottleneck cycle). To clear 8/min the bottleneck must be ≤ 7.5 s/part.

05Retrieve & space

Define the bottleneck of a serial line (the station with the largest time ÷ machines).
Throughput of a line = 60 ÷ ____ (the bottleneck's per-machine cycle).
Adding a machine to a NON-bottleneck station changes throughput by ____ (nothing).

06Mastery & project

Identify and fix the bottleneck so the simulated line meets the throughput target. Proves you can read a line's rate-limiting step.

Bottleneck analysis is the core move of the factory capstone (M5).

← Assembly sequencing Balancing the Line →

VIRTUAL FACTORY

Throughput & the Bottleneck

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.