Food Container Producer

A Midwestern food container manufacturer producing more than 620 SKUs across plastic and foil formats depends on a continuous feed of resin pellets to keep its extruders running. Ten metal silos — each 18 feet in diameter and holding up to 40,000 pounds of pellets — are opaque by design, so operators relied on a manual plumb-bob system to estimate fill levels. Because pellets form uneven cones inside the silos, measurements routinely diverged from actual levels by several thousand pounds. These miscalculations caused multiple extruder stoppages on PET and PLA lines: each stoppage costs more than $450 per hour, requires a minimum two-hour cleanout, and then seven workers four to six hours to restart the line — with a full day of downtime exceeding $10,000.

When a new plant manager joined in 2009, he partnered with Rockwell Automation Global Solutions to replace the plumb-bob process with a continuous, sensor-driven monitoring platform. Laser-array sensors installed inside each of the ten silos stream real-time resin level data to an Allen-Bradley ControlLogix programmable automation controller (PAC) — the core of the Logix Control Platform. Allen-Bradley PanelView HMIs running FactoryTalk View SE software translate raw sensor feeds into role-specific, color-coded level displays for each operator station. Automated alarms fire when levels fall below predefined production thresholds, removing human estimation from the critical path entirely. FactoryTalk ViewPoint extends monitoring to any internet-connected browser, enabling remote visibility across the facility. The legacy plumb-bob system was retained as a verification backup rather than removed, and Rockwell Automation engineers were on-site during commissioning to reduce deployment risk and accelerate operator adoption.

Since deployment, the plant has recorded zero extruder breakdowns caused by resin shortages — eliminating what had been a recurring, high-cost failure mode. Key outcomes include:

• Downtime eliminated: No stoppages on PET or PLA extruders since the system went live, compared to multiple incidents prior to implementation.
• Manual data collection removed: Operators no longer walk to each silo, time plumb-bob drops, or hand-calculate fill estimates — freeing time and removing a primary source of input error.
• Faster response: Real-time alarms give operators lead time to reorder or redistribute resin before a shortage becomes a stoppage.
• Scalability validated: Existing HMI screens, control code, server infrastructure, and IT network are already in place to extend the system to additional facilities with minimal incremental cost.

• Manual measurement of bulk materials in opaque vessels is a hidden reliability risk that can persist even in otherwise well-run facilities — sensor-based continuous monitoring directly eliminates the failure mode.
• Retaining the legacy measurement method as a backup during transition lowers change risk and gives operators a familiar verification tool while they build confidence in the new system.
• Standardizing on a single control platform and programming language (ladder logic across all machines) compounds long-term serviceability and reduces technician training overhead.
• Designing the system for scalability from day one — shared code, screens, and infrastructure — makes multi-site rollout substantially cheaper than treating each facility as a greenfield deployment.