Repair of 44 ton steering hydraulic cylinder of a bucket wheel excavator by Rheinbraun Montan-Hydraulic Repair & Service GmbH Dortmund.
It was the first repair to the steering cylinder since the bucket wheel excavator BG 285 was built in 1975. Wear and enormous impacts had completely destroyed the piston sealing system and the sealing material.
The axial retaining rings for the piston seal had completely come loose from the piston and become stuck in the cylinder tube.
Due to the large amount of leakage via the piston sealing system that had come apart, the forces necessary to move the steering shaft could no longer be achieved. The excavator was not manoeuvrable.
