Rework Reduction - FMCG Manufacturing Line

about this project

When high rework volumes were first flagged to the coaching team, the issue appeared to be in the latter stages of production. At the robot section, biscuits were being missed, damaged, or flipped, and the packaging sealer was crunching packs. The initial thinking was that the two machines, from different suppliers, needed better synchronisation to avoid these defects.


However, deeper investigation revealed that the root cause was further upstream. A warped oven band was producing biscuits with excessive ‘tails’ and inconsistent spacing, which caused both the robot picking errors and the packaging crunching issue.


By flattening the oven band, biscuits arrived at the robot more evenly spaced and with cleaner edges, making them easier to pick and pack correctly. This not only solved the robot and sealer problems but significantly reduced rework, improved quality, and increased efficiency across the line.

Key Project Summary "At a glance"

Project Scope


  • Focus on one manufacturing line producing biscuit products


  • Reduce rework caused by robot pick failures and packaging sealer defects



  • Identify and address the root cause of the problem to deliver sustainable improvements

Improvement Strategy


  • Apply root cause analysis to trace downstream defects back to their origin


  • Repair and flatten the oven band to improve biscuit shape and spacing



  • Monitor line performance before and after intervention, focusing on rework, operator time, and product quality


Benefits Delivered


  • 72% reduction in rework on incomplete or damaged packs


  • 67% reduction in rework from biscuits falling off the conveyor


  • Reduction of 3.5M biscuits reworked annually


  • Saving equivalent to 160 production days of one operator’s time


  • Annual labour saving of £29,000 based on rework time reduction


  • Noticeable improvement in product quality and line efficiency



People Involved

  • Sponsor: Senior Operations Leader
  • Delivery team: Factory Manager and Engineering Team for the line
  • Support: Finance team (validation of cost savings)
  • Role of PBI: Facilitated root cause investigation, coordinated trials, validated results, and embedded monitoring process




Focus Area

  • Primary issue: High rework due to robot mispicks and packaging sealer defects
  • Root cause identified: Warped oven band causing biscuits with tails and inconsistent spacing
  • Impact: Increased rework, lost production time, reduced quality, and additional labour costs
  • KPIs targeted:
  • Reduction in biscuits requiring rework
  • Reduction in biscuits falling off the conveyor
  • Operator hours saved
  • Improved visual quality and pack consistency



Process Taken

  1. Initial observation: Problem first identified at the robot and packaging stages, suspected equipment synchronisation issue.
  2. Investigation: Data collection, line observations, and trials revealed defects originated upstream at the oven band.
  3. Root cause solution:
  • Flattened oven band to restore even spacing and remove biscuit tails
  • Improved product flow into the robot picker and packaging sealer

   4. Performance validation: Measured significant rework reduction and quality improvement post-repair.

  5. Savings calculation: Rework reduction equivalent to 160 operator days, worth £29,000 annually.

   6. Sustainability: Recommendation for band review every 3 years, with replacement if warping reoccurs.