Workforce formula
The number of pieces one operator can make in an hour on an operation, at 100% or from a measured cycle time.
Capacity at 100% = 60 / operation SMV; observed capacity = 3600 / cycle time (s)
| Symbol | Meaning | Unit |
|---|---|---|
| SMV_op | Operation SMV | min |
| t_cycle | Average observed cycle time | s |
Use it in capacity studies and line balancing to see which operators and operations can meet the hourly target.
An operation has an SMV of 0.40 min. At 100%, one operator can make 60 / 0.40 = 150 pcs per hour.
A capacity study times the same operator at an average of 28.8 seconds per cycle: 3600 / 28.8 = 125 pcs per hour. If the line target is 130 per hour, this station is a bottleneck.
Line balancing spreads the operations of a garment across operators and machines so work flows at the target rate without piles of WIP or idle people. A practical step-by-step method with a worked example, balancing efficiency and common mistakes.
A bottleneck is the station that limits the output of the whole line. How to find it with WIP observation and capacity studies, the common reasons a station becomes a bottleneck, and practical ways to raise its output.