Process Variability Reduction in the AC4 Manual Dispatch Workflow at Parker Curtis Instruments PR, Inc.

Abstract

This capstone project evaluated and improved the AC4 material dispatch process at Parker Curtis Instruments PR, Inc. using the Lean Six Sigma DMAIC methodology. The study aimed to reduce delivery time variability, minimize non-value-added movement, improve inventory visibility, and standardize warehouse operations supporting production continuity. Data were obtained from more than 2,140 historical CASTRO records, 320 observed dispatch transactions, 329 part-frequency observations, motion studies, and Voice of Employee feedback. Baseline analysis identified an average dispatch time of 12.45 minutes, a coefficient of variation of 112%, inventory accuracy of 92%, approximately 1,100 feet of operator travel per cycle, and substantial dependence on manual verification. Root cause analysis, process mapping, FMEA, and Lean waste assessment linked these conditions to fragmented storage locations, inaccurate inventory records, inconsistent retrieval methods, congestion, and limited system integration. The improvement strategy combined velocity-based slotting, Golden Zone placement for high-runner components, Standard Work Instructions, barcode validation checkpoints, mini-Kanban replenishment, and milk-run sequencing. Pilot results projected a 25% reduction in dispatch lead time, approximately 20% less motion waste, improved inventory accuracy, and a reduction in process variation to 56% or below. The proposed improvements also generated an estimated annual benefit of $188,036 through recovered space, lower inventory carrying costs, reduced external storage, cycle-time gains, and labor savings. A control plan incorporating KPI dashboards, cycle counts, audits, operator certification, and re-slotting reviews was developed to sustain performance. The project demonstrates how data-driven warehouse redesign can strengthen responsiveness, reliability, and long-term operational control in a complex manufacturing environment and production support efficiency