Changeover reduction for style changes

Learning objectives

• Define changeover from last good old style to first sustained good new style.
• Separate internal and external tasks and pre-stage external ones.
• Reduce startup defects while cutting changeover minutes.

Problem and CTQ

Style change consumes productive time and produces unstable startup quality. The correct clock stops at first sustained good output, not the first piece.

DMAIC path

• Video and time every task; separate internal (line stopped) from external (line running).
• Identify searching, adjustment, approval, material and training delays.

Improvement choices

• Pre-stage tools, materials and programs.
• Quick-release devices and setting standards.
• Parallel tasks, first-piece checklist, skill matrix and rehearsal.

Control plan

• Changeover minutes, first-piece approval time, startup defects, lost output, plan adherence and standard compliance.

Garment-factory example

A jersey line reduces changeover from 92 to 41 minutes by pre-staging trims, moving needle changes external and rehearsing the sleeve-attach fold. Startup DHU falls from 18 to 9.

Common mistakes

• Ending the timer at first piece rather than stable output.
• Trading safety or quality for changeover speed.