Aluminium Based Crankshaft Bearings for the High Speed Diesel Engine

An engine bearing lining alloy of composition Al Si 11 Cu 1 is described which has been developed in the UK specifically for the high speed diesel engine.

The alloy has the advantage of superior seizure resistance when compared with lead bronze on test rigs under conditions of sparse lubrication and controlled misalignment. The alloy is moreover free from the corrosive attack by hot oil to which lead bronze is subject. Evidence from a new design of bearing fatigue rig is presented which shows the strength of the alloy to be equivalent to that of lead bronze. The alloy has been adopted in both the connecting rod and main bearing positions in normally aspirated and turbocharged high speed diesel engines imposing loads on the bearings in excess of 55 MN/m² (8 000 lbf/in²).