Plastic knife edge rollers in beverage plants operate failure-free worldwide

What was needed: A knife edge roller made from the specially developed material iglidur P210

Requirements: High performance requirements (20 units per minute); reliability for round-the-clock use; resistance to sugar particles, sand, dust and moisture in the system as well as temperatures of up to 100°C

Industry: Packaging industry, beverage industry

Success for the customer: The iglidur knife edge rollers are used in Krones systems all over the world and are failure-free. They function reliably, the capping is hardly noticeable. They are also easy to install and save the customer time-consuming maintenance work.

At the Variopac Pro, a fully automatic all-round packaging line, Krones was faced with a challenge in 2005: the plant's output was to be increased by 20 units per minute. There was therefore an urgent need for action on the conveyor belt deflection system.

Originally, metal rollers with needle bearings were used here, but these could not cope with the higher performance requirements and were cost-intensive.
But there are also other challenges here. This is because the Variopac Pro packs cans and bottles made of glass or PET with a size of 0.2 to 5 litres with cardboard and/or film, whereby the system is in operation around the clock and puts a lot of strain on the components. In addition, sugar particles are often present in the production environment, which act like sandpaper on the moving machine components, and that at belt speeds of up to 0.9m/s. Dust, sand and moisture are also part of everyday life where the Variopac Pro is used.

But that's not all. The conveyor belts are permanently exposed to temperatures of up to 100°C directly at the shrink tunnel of the system. Despite these environmental conditions and the performance requirements, the new solution for deflecting the conveyor belts should have a service life of at least one year. The problem here was that a product that could fulfil these performance requirements did not exist at the time.

Before being used in the Variopac Pro, various solutions were tested in the igus test laboratory in order to achieve the desired result together with Krones AG. The result: an injection-moulded solid plastic roller made from a material specially developed for this application. The best test results were achieved with the material iglidur P210. The iglidur knife edge roller is characterised by its high wear resistance, low coefficient of friction and the resulting low drive power of the conveyor belt. In addition, like all iglidur materials, the material is suitable for maintenance-free and lubrication-free use. As it is also versatile, it was possible to fulfil all requirements with one material.

When it became clear that the knife edge rollers made of iglidur P210 far exceeded the required service life of one year, Krones decided to install them in the Variopac Pro. And with great success. According to Krones, the systems, which are used all over the world, work without failures.

The iglidur knife edge rollers work reliably and the closure is barely noticeable. They are also assembly-friendly and save the customer time-consuming maintenance work. Krones now installs the iglidur knife edge rollers in the Variopac Pro wherever there is a transition between two conveyor belts or plastic modular chains. As the knife edge rollers have small diameters, the conveyor belts and modular chains can be guided very tightly and the gap between two belts is therefore very small. Even if the system is running at a low speed, tilting of the packs can be avoided by iglidur knife edge rollers.