How SAPPI’s Ehingen Plant Uses Condition Monitoring to Boost Efficiency and Reliability

At SAPPI GmbH in Germany, condition monitoring has long been the backbone of operational excellence. The Ehingen paper mill—one of seven European plants—produces roughly 250,000 tonnes of paper annually, contributing to SAPPI Fine Paper Europe’s 2.7 million‑tonne global output.

While the industry is highly competitive, downtime costs the plant about €10,000 per hour. Over the past 30 years, SAPPI has transformed its maintenance strategy from reactive to predictive, extending the interval between mandatory shutdowns from every two weeks to every six weeks.

Interview with SAPPI Management

Q: How large is your annual paper output, and what product range do you cover?

A: Burkhard Köhn, Technical Manager – In Ehingen alone we produce around 250,000 tonnes of paper each year. SAPPI Fine Paper Europe’s total output exceeds 2.7 million tonnes, focusing on wood‑free coated paper for high‑gloss brochures, artistic calendars, and art portfolios.

Q: Why is time critical in your manufacturing and supply chain?

A: Köhn – We serve wholesalers who demand high quality and delivery reliability. The mill runs almost 24/7, 365 days a year, so any machine failure cannot be compensated by extra shift work.

Q: What challenges do your machines present?

A: Köhn – Our line is 200 m long, packed with controls, drives, bearings, and gears—every component is a potential failure point.

Q: How do you mitigate those risks?

A: Köhn – Early on we shifted from offline to online condition monitoring. By continuously measuring key parameters, we can detect wear before it leads to costly downtime.

Q: Is plant reliability the key to sustained competitiveness?

A: Köhn – Yes. In an industry under constant price pressure, any extended outage jeopardises our market position.

Q: What makes your plant more reliable?

A: Köhn – We employ 385 sensors across the production line. Our preventive maintenance foreman, Hermann Huss, receives real‑time data on his computer; alarms are triggered when values exceed set thresholds.

Huss – The alarm immediately points to the specific bearing or component that has shifted out of tolerance, enabling rapid response.

Q: What happens when an alarm is triggered?

A: Köhn – Alarms are calibrated based on years of experience; they signal potential issues, not inevitable failures. Live data lets us determine whether a bearing is simply running hotter or truly deteriorating, informing whether to lubricate, replace, or keep it running until the next scheduled service.

Q: How does condition monitoring aid bearing replacement?

A: Köhn – If a cylinder stops rotating, the entire plant stops. Our sensors detect the early warning signs, allowing us to schedule a replacement in 2–4 hours—half the time required without monitoring.

Q: What additional insights do you gain from the data?

A: Köhn – We use the data to both detect damage and optimize bearing life. When a new bearing fails, we conduct a root‑cause analysis and adjust our specifications in partnership with SKF.

Q: Which SKF tools and devices do you use?

A: Köhn – Online monitoring systems, Microlog data loggers for manual measurements, vibration sensors, and specialized evaluation software.

Q: Can you assess any component at any time?

Richard Züfle, Maintenance Manager – Absolutely. Quick, systematic response is our mandate. We aim for planned maintenance every six weeks, preventing unscheduled outages.

Q: Does condition monitoring bring peace of mind at the end of the day?

Köhn – Yes, it does. Huss – Knowing everything is “in the green” is reassuring, though the data also keep us alert to components nearing the end of their life.

Q: Can you quantify the program’s impact?

Thomas Karger, Paper Mill Engineer – Since implementing both offline and online measurements, we’ve identified and addressed 1,000 damage incidents before they caused failures.

Köhn – In 1991, we shut down every other week. Today, the interval between downtimes is six weeks, thanks to condition monitoring.

Q: What’s next for SAPPI Ehingen’s reliability?

Züfle – We’re expanding monitoring to gearboxes, which are strained by our increased production speed of 1,120 m/min. Including them in the program will further safeguard reliability.

Q: Summarise why condition monitoring is essential for SAPPI Ehingen?

Köhn – It enables us to stay at the cutting edge, continuously identify shortcomings, and optimise every bearing in our facilities.