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

At least two years of lubrication-free and maintenance-free operation at 60°C and in continuous use

Stretch blow moulding machines for forming bottles produce high temperatures. This also has an effect on individual components. The bearing of the mandrels on which the bottles pass through the double-gas heating system should therefore meet high standards in terms of temperature resistance. But cleanroom suitability, service life and freedom from lubricants were also in the foreground. The problem was solved with iglidur J bearings and special bearings made of iglidur A180.

Profile

  • What was needed: Plain bearings made of iglidur J and iglidur A180
  • Requirements: Absolute freedom from lubrication and maintenance, heat resistance up to 60°C, cleanroom compatibility
  • Industry: Beverage bottling plants
  • Success for the customer: After tests, KHS calculates that the components will operate for 14,000 hours with the plain bearings for the mandrels. This corresponds to two years of completely maintenance-free and lubrication-free operation.
Transport mandrels with iglidur plain bearings and sliding elements transport preforms through the KHS stretch blow moulding machine.

Problem

In addition to the production capacity of up to 81,000 PET bottles per hour, the InnoPET Blomax stretch blow moulding machine series from KHS also impresses with its double-lane heating concept.
This means that two rows of bottles are heated side by side here in order to give them the appropriate shape. The benefit goes beyond the 30% more energy that can be saved in this way. The KHS engineers also wanted to make the stretch blow moulding machine as durable and maintenance-free as possible.
Decisive for this are, among other things, the mandrels on which the premoulds are transported through the near-infrared heating. They use plain bearings, which must not only be designed for high temperatures. They should also be cleanroom-compatible, food-compliant and, above all, maintenance-free.

Solution

The plant specialist chose plain bearings in the mandrels for the iglidur range. A total of two bearings are used per mandrel, with only one from the catalogue product range. The iglidur J catalogue bearings used in the so-called tulip is accompanied by another bearing in a special shape, which we manufactured from the iglidur bar stock A180 by machining.
A very important thing here is that the material of the bearings does not require lubrication and is therefore ideal for the food sector in particular. With the bearings, maintenance can also be dispensed with. And extensive tests on a prototype at KHS also showed how long the user can use the bearings. KHS places the service life at 14,000 hours, i.e. two years of production, and that at temperatures of up to 60°C and under continuous load.
Transport mandrels Transport mandrels with iglidur plain bearings and sliding elements transport preforms through the KHS stretch blow moulding machine.
Double lane heating The double gas heating system heats up premoulds and saves up to 30% energy.