37% More Modules a Day, From the Same Plant

The Situation

The line looked busy on reports, but output was leaking in small, frequent losses that no one system was surfacing clearly.

Stringers idled waiting for reworked strings, cleaning stages ran longer than needed, and auto-bussing recalibration frequency quietly pulled performance down.

Because each loss was small, it was tolerated. Together, those losses held the bottleneck at 38.4% OEE with availability around 60%, and capped plant output.

What We Did

We started at the constraint and made losses visible by station and shift before changing methods line-wide.

• Built a floor data layer with revised production formats, hourly boards, and a live OEE dashboard.
• Ran time-and-motion plus Yamazumi analysis, then validated bottleneck fixes through controlled proof-of-concept trials.
• Standardized the rework-string process to remove repeat stoppages at stringers.
• Embedded TPM into daily work through autonomous maintenance, revised checklists, and fuguai closure.
• Reduced cycle time at manual cleaning and final inspection by about 35-37% through method redesign.

The Results

Daily finished output increased from 1,404 to 1,923 modules in six months without adding a new line or building.

Stringer OEE moved from 38.4% to 53.7%, availability improved from 60.6% to 75.5%, and standardized rework alone removed about 449 minutes of stoppage each month.

The internal team now runs daily reviews with a maintenance discipline that sustains the gains.