A OEE como bússola de melhoria em uma linha de blocos de concreto: estudo de caso com SMED e A3

Abstract

This study describes the application of the OEE indicator in a semi-automated concrete block production line located in Uberlândia, Minas Gerais, Brazil. After mapping the process into seven stages—from dosing to palletizing—daily data on production, quality, maintenance, and external testing were collected and consolidated into monthly spreadsheets. OEE was calculated based on its three pillars (availability, performance, and quality), using an internal target of 83.7%. Pareto, Ishikawa, and 5 Whys analyses showed that dimensional variation, deformation, and burrs accounted for 80% of scrap. Root causes were documented in A3 reports and addressed through countermeasures such as SMED, start-up checklists, weekly sensor calibration, and the installation of a top scraper. Between 2021 and 2025, unplanned downtime decreased by 35%, mold changeover time was reduced from 45 to 28 minutes, and the out-of-specification rate dropped to 0.4%. OEE improved from 62% in the first measurements of 2020 to 90% in December 2023 and remained at a level close to the internal target through May 2025, indicating that simple and disciplined adjustments increase operational efficiency and contribution margin.