Fruit Processing company Zentis implements a cool condition monitoring solution from Schaeffler

Global automotive and industrial supplier Schaeffler has supplied a fruit processing company with its ProLink condition monitoring system to monitor the condition of trolley bearings on stacker cranes, which operate in cold and frozen storage areas. 

Zentis GmbH & Co. KG, with its headquarters in Aachen, Germany, is one of Europe’s leading fruit processing companies, producing jams and fruit preparations for the baking, confectionery and dairy industries.  

The Aachen site uses large stacker cranes for storage, transfer and retrieval. In order to monitor the large and difficult-to-access moving components in the cold and frozen storage areas and to avoid unplanned downtime, the logistics team at Zentis was looking for a predictive maintenance solution.

Zentis had previously implemented Schaeffler’s SmartCheck condition monitoring devices on gearboxes and cable reels to monitor the health of a critical pallet lifter. The devices have helped to prevent unplanned downtime and optimise production. If the pallet lifter fails, the first production stoppages occur around two hours later. The SmartCheck devices measure the vibration, speed, temperature and imbalance of various rolling bearings in the gearbox, as well as the gear teeth/mesh. The CM solution has enabled an early warning period of several weeks which allows Zentis to carry out repairs and remedial action as part of planned maintenance work, thereby avoiding costly unplanned downtime.

In the cold and frozen storage areas at Aachen, a different kind of CM solution was required. The stacker cranes constantly move around the 30-metre tall racks in different directions. The trolley bearings, in particular the non-driven bearings, are highly stressed. The fact that constant measuring conditions do not exist during regular operation posed an even greater challenge. In addition, temperatures in the frozen storage area are as low as -20°C, which presented yet another challenge for the new measuring system, for example, how to attach the sensors to the measuring points.  

Michael de Ben, Head of Internal Logistics at the Aachen site, comments: “We were looking for a monitoring solution for our stacker cranes that could reliably take measurements despite inconsistent measuring conditions and ultra-low temperatures in order to protect us from unplanned downtimes.” 

After approaching one of Schaeffler’s local authorised sales partners the Schaeffler ProLink condition monitoring system (CMS) was chosen. This intelligent measuring concept was adapted to suit Zentis’ unique requirements.  

To monitor the stacker cranes, a Schaeffler ProLink CMS and five sensors (bearing guards) were installed on each stacker crane unit. In order to perform meaningful vibration monitoring, the original measurement concept had to be changed in the multi-channel CMS. Schaeffler achieved this by breaking down the short, slow travel times into many short measurements. Any extreme impacts could then be determined from these measurements. 

To solve the temperature challenge in the cold storage area, the ProLink CMS was installed in the switch cabinet. In the frozen storage area, the ProLink system was placed in heated control cabinets that escort each stacker crane run. The sensors were attached to the measuring points using a special, cold-resistant adhesive compound.