Extending Mixer Lifetime Through Refurbishment

Reducing downtime and upgrading to food-grade standards

When mixing equipment no longer meets operational or regulatory requirements, refurbishment and retrofit can provide a more effective solution than full replacement. For Plantextrakt in Germany, Hosokawa Micron refurbished two Nauta^® conical screw mixers to restore process reliability, reduce maintenance costs and meet current food-grade standards.

Rather than replacing the mixers, the project focused on improving the existing system. This approach allowed Plantextrakt to extend equipment lifetime while maintaining production continuity and limiting investment.

Mixing of herbal extract powders

At its production facility in Kleinostheim, Plantextrakt processes herbal extracts using Nauta® conical screw mixers by Hosokawa Micron. After more than three decades of operation, the mixers increasingly suffered from mechanical failures. This resulted in recurring downtime, rising maintenance costs and growing pressure on production reliability.

At the same time, the equipment no longer met current food industry standards. A failed customer audit highlighted the urgency of improving cleanability and upgrading critical components to food-grade design.

From equipment issues to process assessment

Hosokawa Micron’s service team carried out an on-site inspection to assess both the mechanical condition and the process implications. The evaluation showed that the flat cover design limited cleanability, while the drive system presented risks due to non-food-grade lubrication and potential leakage.

In addition, wear in key components such as the bottom bearing and mixer arm contributed to increasing maintenance frequency. Instead of recommending new equipment, Hosokawa proposed a refurbishment strategy focused on eliminating these constraints and aligning the mixers with current operational and regulatory requirements.

Due to the nature of retrofit projects, final adjustments were made during installation. The mixing screw was further optimised on site by slightly reducing its diameter and adding an additional flight to achieve the required performance.

Despite these adjustments, the project progressed smoothly. Careful preparation and coordination ensured that the shutdown period remained controlled and that all modifications could be implemented within the available timeframe.

Improved reliability and extended lifetime

The refurbishment was completed ahead of schedule, reducing the planned downtime and allowing production to resume earlier than expected. Following the upgrade, the mixers operate with improved reliability and significantly lower maintenance requirements.

By refurbishing instead of replacing the equipment, Plantextrakt achieved a substantial extension of service life, while also meeting current food-grade standards and improving overall process stability.

Refurbishment as part of powder processing optimisation

For many industrial powder processing systems, performance limitations are not caused by the core equipment design, but by wear, outdated components or changing regulatory requirements. In these situations, refurbishment and retrofit provide a practical route to improve process performance without replacing complete installations.

Hosokawa Micron approaches these projects from a process perspective, combining mechanical engineering, application knowledge and system integration. This ensures that upgrades are not limited to individual components, but contribute to overall process reliability and efficiency.