Process Improvement: Removal of the Second Alkaline Cleaning Step in Dual‑Anodized Products

Abstract

This study addresses the removal of the second Alkaline Cleaning step in the dual-anodized process for titanium medical device components, which currently involves Color Anodize followed by Type II Anodize. Repetition of this cleaning step exposes silicone masking plugs to elevated temperatures, weakening their integrity and increasing the risk of cosmetic or functional defects. In addition, the redundant operation extends cycle time by 8–10 minutes per lot and reduces equipment availability. A structured validation methodology was applied, including risk and impact assessments, baseline scrap data review, confirmation runs, and operator readiness activities. Results demonstrated a significant and sustained reduction in scrap levels after eliminating the second cleaning step, with stability observed for multiple consecutive months. Process parameters remained within compliance, and throughput efficiency improved without compromising inspection rigor or product quality. The improvement aligns with lean manufacturing principles by eliminating non-value-added activities and strengthening process reliability. Keywords ⎯ Alkaline Cleaning, Anodize Process, Lean Manufacturing, Scrap Reduction.