Maintenance-free at 3,000 cycles per day - bearing technology in conveyor systems for paper and polystyrene

What was needed: Lubrication-free bearings in the conveyor technology for processing paper and polystyrene

Requirements: Freedom from lubrication, minimisation of service calls, trouble-free operation, precision, smooth operation even in high-speed motion

Industry: Material handling

Success for the customer: Lubrication-free and maintenance-free linear bearings, flange mounted bearings, slewing ring bearings and plain bearings protect the paper and polystyrene plates from contamination by lubricating greases. Reliable and precise operation is ensured even at 3,000 cycles per day. Online tools such as a service life calculator and an online CAD database have made it possible for customers to find products quickly.

Unipack is a Czech manufacturer of conveyor systems that offers a broad portfolio ranging from individual roller and rotary conveyors to turnkey systems. The supplier was looking for rotary and linear bearing products to align and transport paper and polystyrene for a customer.

Unipack's task: At the end of the production line, large polystyrene blocks were to be transported from the ground floor to the warehouse on the second floor. For this purpose, the system manufacturer designed a rotary conveyor, a lifting conveyor and a forklift to place several polystyrene sheets on top of each other for better onward transport.

Unipack's engineers had to take into account some specific requirements for the production and handling of paper and polystyrene for the implementation:

To avoid contamination of the paper or polystyrene, Unipack was looking for bearing technology that works completely without external lubrication. In addition, all components had to be able to operate for as long as possible without maintenance, as parts of the system have a reduced oxygen content for fire safety reasons and are therefore more difficult to access. However, the performance target set for the conveyor technology and the lifts in the plant - at 3,000 cycles per day - also required operation to be as trouble-free as possible.

Before Unipack decided on specific bearing products in conveyor technology, the plant manufacturer worked intensively with the service life calculator on the igus website to find out about product-specific durability and used the online CAD database. Together with comprehensive advice from the igus sales team, Unipack decided in favour of motion plastics in all conveyor technology stations:

In several rotary tables, PRT slewing ring bearings of type PRT-01-100 were installed, which have a long service life, require no external lubrication and, above all, enable high precision.

The lifting conveyor was equipped with six drylin W linear guides and several dozen carriages of types WJ200QM-01-16 and WJ200QM-01-25. Thanks to the tribopolymers with integrated solid lubricants installed in the sliding elements, they also enable operation without external lubrication and maintenance. The linear plain bearings support high movement accuracy at high lifting speeds.

Finally, the conveyor technology specialist also relies on tribopolymers in the forklift: Two pivotable plates press against the incoming polystyrene block from the right and left, lift it and place it on the next one. Due to the high load and the required mechanical strength in the forklift, KFSM-GT40 flange mounted bearings were used to hold the pivoting side plates of the forklift. JFM-2023-21 plain bearings are also used here.