Composite materials for bearing bonding to secure rudder integrity

Rudder bearing structure Corroded housing

The use of composite materials offers an alternative to traditional press and freeze fitting that ensures not only accurate alignment but also long-term secure location of the bearing. Alice Jucquois reports

The critical requirement with rudder bearings relates to the bush retention in the housing. Because the bush is manufactured from a different metal to the bearing block, local galvanic corrosion can occur, which causes the housing to become over-sized until eventually the bush can no longer be held in the correct alignment. This misalignment can result in the development of annular gaps between the housing and the bearing bush, resulting in excessive and premature bearing wear, a malfunctioning rudder and, consequently, costly repairs and loss of sea time.

Due to a combination of severe vibration, constant fretting and an aerated sea water environment, bearing installation can be a real challenge. The ideal installation would provide a perfect seal between the bush and the housing while offering a complete corrosion protection.

Bearing housing installed using composite materials

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