Plastic Bearings in Filling PET Bottles

Wear-resistant iglide® J
In the case of Krones' pull-back star, three iglide® J products are used in the staple carrier. The two upper glide bushings thereby form the fixed bearing, the lower glide bushings, the torque arm, functions as floating bearing. Per rotation of the decoupling system, the bearing must travel a stretch of around 100 mm, which – based on the service life – corresponds to an overall mileage of 1802 miles. In the process accelerations up to 1.35 g and speeds of 0.56 ft/s mm/s are achieved. Krones' developers rely on iglide® J flange bushings also for cam rollers. They guarantee the clean and uniform rolling of the plastic cam rollers on the cam track.

The radial forces of the cam rollers are reliable and smoothly transferred to the staple carrier. The turning bolt in turn is mounted in an iglide® X plastic bushing. With its rolling-off movement at the control cam, it provides for a precise and position-based opening and closing of the bracket. The carriage is also equipped with soft stainless steel round guides like the staple carrier housing. If required, for instance, in emergency stop situations the carriage should complete the switching movement within 590 ft. This requires a reliable and stick-slip-free gliding movement, as the entire system accelerates at 2.45 g and achieves a speed of 1.4 ft/s on the short stretch of 1.6 in.

The compression springs, which holds the staple carrier on the pitch circle, are guided on one side with an iglide® J plastic bushing. They center the compression springs on the staple carrier and prevent mechanical damages of the highly polished round guide surface.

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