14,000 hour service life: iglidur plain bearings in KHS stretch blow moulding machines

In addition to its production output of up to 81,000 PET bottles per hour, the InnoPET Blomax stretch blow-moulding machine series from KHS also impresses with its double-aisle heating concept.
This means that two rows of bottles are heated side by side in order to mould them into the required shape. This not only saves 30% more energy. The engineers at KHS also wanted to make the stretch blow-moulding machine as durable and maintenance-free as possible.
Among other things, the mandrels on which the premoulds are transported through the near-infrared heating are crucial for this. Plain bearings are used in these, which not only have to be designed for high temperatures. They should also be cleanroom-compatible, food-safe and, above all, maintenance-free.

The plant specialist opted for the iglidur® range for the plain bearings in the mandrels. A total of two bearings are used per mandrel, whereby only one comes from the catalogue range. The catalogue bearing iglidur® J used in the so-called tulip serves to rotate the PET blank and has a low coefficient of friction here (see Fig. 1). It is accompanied by a linear bearing in a special shape for the linear stroke in the double-aisle heater, consisting of the material iglidur ® bar stock A180 (manufactured by machining, see Fig. 2). The lubrication and maintenance-free material A180 is FDA and EU10/2011 compliant and therefore predestined for the food sector. Extensive tests on a prototype at KHS showed how long the user can utilise the bearing. KHS puts the service life at 14,000 hours, i.e. 2 production years, and this at up to 60 °C heat and under continuous load.