Migración del control analógico - Manual a un control digital - Semiautomático para la elaboración de botanas a base de maíz por proceso de extrusión

Abstract

This project presents the migration from an analog–manual control system to a digital–semi-automatic control system for the production of corn-based fried snacks through an extrusion process. The modernization initiative arose from several issues identified in the original production system, including variations in ingredient dosing, long downtime caused by electrical failures, low repeatability in operating cycles, and a high volume of product rejected for not meeting established quality specifications. These problems not only increased production costs but also compromised the consistency and standardization required in the final product. To address these deficiencies, a new digital control architecture was designed and implemented using a PLC, an HMI, and variable-frequency drives, supported by a redesigned electrical panel and updated wiring diagrams. The system incorporated sensors, actuators, and calibrated measuring devices such as water and oil flowmeters and a flour weighing module. Programming was carried out according to international standards, including IEC 61131-3 for PLC programming and ISA 101 for HMI design, ensuring a structured, reliable, and user-friendly control platform. The digital system replicated the operation of the previous analog control while adding precision, stability, and enhanced monitoring capabilities. The implementation process involved equipment relocation, integration of mechanical and electrical updates, real-world operational testing, and training of production, maintenance, and quality personnel. Through iterative adjustments, the system successfully matched and stabilized the timing and sequences previously achieved under manual control. Alarm-based diagnostics and real-time visualization improved fault detection, operational safety, and process traceability. The results revealed significant improvements in production performance. Downtime was reduced by more than 95%, decreasing from interruptions of up to two hours to only a few minutes. Product rejection decreased by up to 85.7% per week due to improved process stability and more accurate ingredient dosing. Additionally, the digital IV system increased overall operational efficiency, optimized resource utilization, and provided a scalable automation foundation aligned with the ISA-95 automation pyramid for potential future expansions. In conclusion, transitioning to a digital–semi-automatic control system substantially enhanced the reliability, efficiency, and quality of the corn snack production process. The project not only resolved critical limitations of the analog system but also positioned the company to adopt more advanced and competitive automation technologies in the food manufacturing sector.