Roll bending machine

The steel plate manufacturer Dillinger Hütte urgently required the repair of a lateral roll cylinder at a time of completing a bulk order. It is a part of a roll bending machine for producing large pipes, that could not remain out of action for longer than one weekend. When the customer delivered the cylinder Montanhydraulik Reparatur und Service GmbH carried out the disassembly and assessment.

The findings were as follows: Serration and wear-and-tear of the bronze guide rails fastened on the side of the cylinder. The consequence: The bronze guide rails had to be renewed. The new guide rails were supplied at short notice and mounted on the cylinder barrel. The new guide rails were supplied at short notice and mounted on the cylinder barrel. Then they were machined accurate to a tenth of a mm.

The hydraulic cylinder was finally assembled, filled and tested during a night shift in an operation which lasted from the night before the second weekend to the next morning. The cylinder was dispatched on the same day, installed in the roll bending machine in Dillingen and was commissioned that weekend.

The following requirements were successfully fulfilled in record time:

  • maximum 9 days repair time
  • replacement and machining of the bronze guide rails
  • polishing of the piston rod
  • replacement of the seals
  • assembly of the hydraulic cylinder
  • filling with hydraulic oil
  • complete testing

Hydraulic cylinder:

  • weight: 17.7 t
  • piston diameter: 840 mm
  • rod diameter: 500 mm
  • total stroke: 1,820 mm