Case Study: Improving Shift Performance with Short Interval Control at Summit Plastics
Summit Plastics, a leading manufacturer of custom plastic components, was struggling with inconsistent shift performance and frequent production shortfalls. Supervisors were reviewing key metrics, such as throughput and downtime, only at the end of each shift, often discovering issues too late to correct them in real-time. This reactive approach led to frequent overtime, missed production targets, and increased scrap rates. Leadership recognized the need for a more proactive system to identify and resolve issues as they occurred.
To address this, Summit Plastics implemented Short Interval Control (SIC) as part of their daily operations. The team divided each 12-hour production shift into two-hour blocks, with operators and supervisors reviewing key metrics—such as cycle times, downtime, and quality defects—at the end of each interval. These reviews took place during quick stand-up meetings at the line, where the team would immediately discuss any variances from targets and agree on corrective actions before moving into the next interval. SIC boards were installed at each workstation to track real-time performance and provide visual cues.
The results were quickly felt across the plant. Within six weeks, Summit Plastics improved schedule adherence by 16% and reduced downtime by 14%. By identifying emerging problems earlier, teams were able to resolve machine stoppages, adjust staffing, and manage material flow before issues escalated. Operators became more engaged in problem-solving, taking ownership of performance metrics and contributing to continuous improvement ideas. Additionally, the SIC process helped supervisors shift from a purely reactive stance to one where they could coach teams in the moment and prevent production losses within the same shift.
Culturally, the shift to Short Interval Control fostered a sense of urgency and accountability throughout the production floor. Teams reported higher morale, as they could see the tangible impact of their decisions and actions in real-time. Leadership also gained more granular insights into production trends, which were later used to fine-tune staffing models and maintenance schedules. By breaking shifts into smaller intervals and making performance visible at frequent touchpoints, Summit Plastics created a more responsive and productive operating environment, positioning the company for sustained operational excellence.