From time to time, the propeller would strike a log or piling instantly shearing the pinion shaft in the reduction gear. This resulted in costly rebuilds and downtime on a regular basis.


The existing drive configuration, a typically tight marine envelope, limited our options. The close connection between the engine and gear prohibited any high speed approach. This only left the tail shaft connection.

We developed an assembly to handle the 1055 HP (787 kilowatt) diesel drive using only five axial inches. Despite the short length, they will still need to modify the tail shaft or move it aft.

This design will completely disconnect upon overload. The initial unit is adjustable from 127,560 in-lb. (14,412 nM) to 701,580 in-lb. (79,268 nM). We can upgrade to 1,169,300 in-lb. (132,113 nM). (With the installation of additional elements, we are evaluating both taper roller and sleeve bearing designs).