RD Flexible Shaft Couplings are designed to provide flexible connections between a propeller shaft and gear box, compensating for the motion of soft-mounted engines and reducing gear whine.
An RD Flexible Shaft Coupling consists of a spool specially machined to mate with the gear flange, plus an aluminum element and shaft hub. The aluminum element holds a series of pre-compressed rubber blocks - bolts are inserted through these blocks to attach to the spool. These rubber blocks allow the coupling to be flexible radially, while stiffer isolation rings at the center provide axial stiffness to allow the efficient transmission of propeller thrust.
For vessels with remote thrust bearings, water jets, or Z drives, we offer a version without the thrust elements.
With no metal-to-metal contact between the gear and shaft, these couplings are highly effective at eliminating gear whine. Gear whine has a distinct tonal quality that makes it especially annoying, and it is often mistaken for noise from the turbo.
RD Flexible Couplings should be considered for any vessel where reducing noise levels is a priority. This is especially true for vessels with aft cabins, V drives, or where the aft salon bulkhead is in close proximity to the aft engine room bulkhead.