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Dummy Bar Disconnect Cylinder Upgrade

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A steel processor was experiencing hydraulic cylinder failure on the caster dummy bar disconnect cylinder. Failures were so common and repair times so lengthy that three spares were required for one operating unit.


  • An exhaustive study of the application was done.
  • The equipment was observed in operation and production and maintenance personnel were consulted.
  • A course of action which included:
    • Redesign of rod end to allow for easier disassembly
      • Typical rod end removal required in excess of eight hours.
    • Redesign of the rod bearing gland.
      • Increase load bearing area.
      • Material change.
      • Redesigned seal cavity dimensions and configuration.
    • Redesign Cylinder head, rod end and rod gland water cooling system.
    • Install anti-rotational mechanical device to insure rod end registration.


  • Cylinder average duty cycle went from weeks to over a year.
  • Disassembly and assembly time of the cylinder was decreased by 50%+