Using OEE and SPC to improve quality and productivity

Quality is the process of producing products that meet specifications. It is but one of three elements of Overall Equipment Effectiveness (OEE), the other two being uptime and rate. It is fair to say that we cannot produce quality without measurement. We may either measure to insure that our processes are in control and thus infer that product quality is achieved or we may measure product attributes directly to insure quality. Product attributes may be measured in-line, near-line, or off-line in a laboratory. Typical hybrid manufacturing/packaging operations perform a combination of all of these to insure product quality.

In today's world, when we discuss production, quality is assumed. Once basic quality and product safety issues are addressed, much of the quality discussion resembles a productivity discussion. In this context, Don Enstrom, Senior Director Manufacturing & Engineering Services at Cliffstar Corporation shared experiences with Packaging Automation Forum attendees about the implementation of Overall Equipment Effectiveness (OEE) and Statistical Process Control (SPC) solutions that improved quality and prductivity.

Cliffstar (which has been acquired by Cott Corporation) has a disruptive manufacturing environment, with the record for changeovers on a single line being forty-two in one day. This amount of disruption can surely lead to variability that presents opportunities to achieve both quality and efficiency benefits.

In its juice bottling plant, Cliffstar was challenged with both direct material losses, process variability (quality) losses, and labor efficiency losses. By reducing these, Cliffstar saw potential to increase capacity, reduce capital, improve performance and quality and improve customer and consumer satisfaction.

A two-step strategic plan was created to maximize return on investment. Step one was to develop a continuous improvement model using manual measures and basic lean and six sigma tools that would be implemented at all sites. Step two was to provide automated real-time performance measurement in a phased installation of a scalable system and compare its results to those from the manual system. As this OEE-based system was being expanded, a pilot of SPC was planned.

As this plan developed into the first full site implementation, plant line efficiencies responded in the first 30 days. Results were a 3.1% higher average efficiency 5 months into the project. This pilot delivered an internal rate of return of 157% which extrapolates to a potential $3 million near term savings across 5 plants. The SPC pilot implementation resulted in reducing bottle overfill by 76% in the first 30 days and indicates a short term potential 5 plant opportunity of $1.1 million.

At-line SPC measurements of bottle fill may lead to additional quality measurements such as cap torque. These measurements can work their way into engineering for design and maintenance improvements. Line associates are more enthusiastic about working on performance problems given real data rather than the erroneous data that used to be provided from manual systems. One problem that remains to be addressed by Cott is the ongoing support challenge of a system that cuts across both engineering and information technology departments.

Nevertheless, these results have guaranteed ongoing executive sponsorship. What has been your experience with using OEE or SPC to improve quality and productivity?