Many components of a self-contained hydraulic motor/propeller unit for power boats are cast in Ferralium® 255, where mechanical strength and resistance to sea water corrosion are both essential to durability.
The unit, made by the Lucas Aerospace Ltd. hydro-mechanical group of Bracknell, Berkshire, offers many installation and operational advantages:
- Almost any mounting can be adopted.
- A gearbox with drive shaft is unnecessary.
- Vibration is considerably reduced.
- Infinitely variable speed is possible with a governed engine speed.
- A single lever controls any propeller speed from full ahead to full astern, making reversal practically instantaneous.
Materials used
Ferralium® 255 (UNS S32550, Alloy 255, DIN 1.4507, ASTM F61) castings include the rod ends, mounting brackets, steering gearbox pedestal and mounting ties. The upper stem journal is in HIDURAX 1 aluminium-bronze, which combines good bearing properties with mechanical strength and corrosion resistance.
