Chemical-resistant special bearing in beverage filling valve

The KHS filling system for beverages containing CO2 utilises a patented filling valve in which the PET bottle is pressed by the product pressure. The bellows, which generate the contact pressure, must be able to move axially without contact in the surrounding hole. The piston on which the bellows presses must also be able to move axially in the hole, regardless of the current bellows length. For the axially movable centring of the bellows, the designers were looking for a special bearing that can withstand operating temperatures of up to 140°C and is resistant to all cleaning agents used in the beverage industry.

The perfect solution was found at igus®: a plain bearing in a special shape made of iglidur® X material, which is universally resistant to chemicals and exhibits very good wear resistance at high temperatures. It is attached to the bellows with a snap connection and slides in a hole, with axial relief grooves on the outer diameter of the bearing preventing pumping effects. The bearing is convincing across the board: no measurable wear was detected in the 50 million stroke test.