Lubrication-free bearings and drive elements in thermoforming packaging line

• What was needed: drylin® W linear bearing technology, drylin®JUM linear plain bearing, iglidur ® plastic plain bearing, xiros polymer ball bearing, DC servomotor, iglidur ® plain bearing, dryspin® trapezoidal threaded spindle, energy chain
• Requirements: Lubrication-free bearings were required that can withstand aggressive cleaning processes, e.g. under hot steam and particularly humid, warm or cold environments without any problems.
• Industry: Packaging industry, food industry
• Success for the customer: The energy chain, linear bearings, threaded spindles and ball bearings can be used under the strict specifications of the food industry and have been developed for lubricant-free and maintenance-free use under aggressive environmental conditions.

During thermoforming, a bottom film is placed in a tray mould, the goods are inserted and sealed with a top film. Storage technology was required at various points in the PowerPak PLUS packaging system:

Bottom film unwinding
A sliding door on the safety housing of the bottom film unwinding system requires curved linear bearings that follow the contour of the reel. They have to manage without active lubrication and be able to cope with cleaning processes using hot steam, acids and alkalis or dry ice.

Film deflection
A 3 metre wide sliding door at the height of the film deflector in the centre section of the system also provides visibility and access to the machine.

Tensioning system
An adjustable guide roller maintains the web tension when the film is unrolled and is retracted linearly when the film is changed. For this and for the storage of the guide roller itself, storage technology was required that prevents electrostatic charging of the film and can be operated completely lubrication-free.

Web edge regulation
In addition to the web tension, the packaging system also monitors the longitudinal direction. If the film width changes, a sensor transmits this information to a servomotor, which adjusts the roll axially via a linear unit.

Thermoforming and sealing station
At this station, the bottom film is given its shape under the influence of pressure and heat. Lifting stations with linear lifting and toggle lever systems allow the moulds to move in a vertical direction. Sliding and linear bearings are required for their axis.

Labelling station
Finally, a solution also had to be found for the energy and signal supply of the system's labelling dispenser that could be used under the strict specifications of the food industry.

GEA Food Solutions now uses our storage technology at various points in its packaging line in order to meet the expectations placed on storage technology:

drylin® W linear bearings
The curved contour of the sliding door device on the bottom film unwinding is solved using drylin® W linear systems. Sliding elements made of tribo-polymers with incorporated lubricant run on them so that they do not require active lubrication.

drylin® W linear bearing
The drylin® programme is also used in the sliding system at the level of the film deflection. They are also suitable for aggressive cleaning processes.

drylin® JUM linear bearing, iglidur® bearing, xiros ball bearing
The linear adjustment of the tensioning system is performed by a drylin® JUM linear plain bearing. A triboplastic bearing made of conductive iglidur® F2 prevents electrostatic charging of the film. xiros polymer ball bearings are used for the bearings of the guide rollers. The xiros design makes complex sealing concepts superfluous.

DC motor, dryspin® Trapezoidal threaded spindle
The readjustment of the roller drum in the longitudinal direction is made possible by a DC motor that drives a dryspin® trapezoidal threaded spindle; a lead screw nut made of iglidur® triboplastics moves the roller axially.

iglidur® plain bearing, drylin® linear foils, iglidur® linear clip bearing
The axis at the drawing-in and sealing station are mounted in plain bearings made of the materials iglidur® J and Z, which absorb high forces. For the linear strokes at the station, drylin® linear foils and iglidur® JUCM linear clip bearings were installed.

energy chain
Our product range also guarantees reliable function for the energy and signal supply. Energy chains suitable for the food industry are used here.