A molded plastics manufacturing company was dealing with major quality issues. Their equipment was not consistently producing good product. To compensate, employees were being moved from running production to non-value adding work to mask the quality problem by trimming flashed plastic on ready-to-ship products.
Demand was increasing 10-15% YOY, but capacity was stagnant as employees were shifted from production, and OEE was falling because of an inability to consistently make a good product without flash. The quality issue was stifling growth and they were consistently shorting orders. Customer complaints flowed in - if they could not fix their problems, they might lose their biggest customer.
The organization was trying to apply a number of lean tools to try to meet demand and run a lean organization. To prioritize and plan for the day ahead, the facility tracked scrap, machine repair schedules, and operator staffing. Despite these improvement tools, the plant felt unable to make improvements. With each passing day, Cost of Poor Quality was increasing until it reached millions of dollars. Leadership decided they could no longer work around the problem and called in Stroud to help tackle the flash problem at hand.
The Necessity of a Focused Project Scope
Since many products had quality defects, solving all of them at once would require focusing on too many number one priorities at the same time. To determine the top priority, the Stroud and plant team conducted a thorough financial analysis, which included quantifying the cost of additional labor for trimming flash and conducting inspection activities, the cost of wasted raw material, and the cost associated with missed sales and defective products. Reviewing the costs by product type, the team confirmed that solving flash just on a few high-volume products would yield significant gains for the plant.
Solving the Problem
Employing a tool called Variable Analysis, the team worked to determine the culprit behind flash. Understanding that flash is a function of how well the molds can contain the molten plastic, the team organized a test to visually check how well the seal is formed when the mold is closed. The team worked to get as much information out of the test as possible, turning what used to be a binary yes/no test into one where much more data was gathered. Quality of contact when the mold is closed was evaluated at discrete sections, and the cause of poor contact was attributed to one of five fault types.
Correlating locations, characteristics, and sizes of contact gaps with the flash seen on parts that came from the molds, the data showed that poor mold contact was responsible for >80% of flash. The only common link for all instances of poor contact was the lack of complete, routine maintenance ensuring that the molds would fully close.
Implementing the Solution: Facilitating Communication
Once the team found that more focused maintenance would be the best way to eliminate flash, it was time to create a plan to sustain consistent maintenance and push tackling the maintenance backlog. Since maintenance events take equipment offline for 2-3 weeks and cost tens of thousands of dollars per event, it is not simple to conduct these events. They require thorough planning.
The team developed a top-to-bottom approach when creating a maintenance plan, ranging from full 6 month schedules to daily activities to be completed. The day-to-day activities included a standard SOP to conduct part inspections and regular cleanings to monitor mold health and increase the time before performance starts to decline. Implementing these activities in the ninth week of the project brought clear results: plant productivity was increased 15 percentage points in 5 weeks.
For planning the longer maintenance events, the Stroud and client team worked to develop a comprehensive capacity plan, taking in demand forecasts from clients, inventory levels, and work-in-progress reports from SAP. This capacity plan gave the plant the ability to select a mold maintenance time, showing the effects on inventory and production.
The team concluded the effort by wrapping together the full maintenance program, which involved coordination from the quality manager, tooling, maintenance, engineering, operations, and planning. Having demonstrated success, the client decided to roll out similar programs at other manufacturing facilities. Armed with a structured steering process, KPI tracking, goals, and mutual accountability, the client was set to meet their growth targets with well-maintained machinery.
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