R & D Marine 910-002 R&D Flexible Shaft Coupling for 4" Yanmar - 3HP/100RPM

Flexible Shaft Coupling for 4" Yanmar - 3HP/100RPM

The R&D Flexible Couplings are manufactured using a contoured flexible disc made of a durable polyurethane material. This innovative design allows for free flexing to accommodate any temporary misalignment between the engine and shaft, which may occur due to the natural movement of the boat or the engine's position on its isolation mountings.

Forward and reverse thrust is handled in compression on the disc positioned between two half couplings, and in the event of a disc failure, steel straps ensure a fail-safe mechanism that keeps drive intact in both directions.

Power Calculation for Coupling:

To determine the appropriate power of the coupling required, the formula is as follows: Horse Power of Engine _{x Reduction Ratio x 100 = HP/100RPM}. For example, a Ford engine with 150HP operating at 2500RPM and a 2:1 reduction ratio would yield: 150/2500 x 2 x 100 = 12HP per 100RPM.

The R&D Marine Flexible Coupling is designed to fit between the transmission output flange and the shaft coupling, effectively safeguarding the boat's drivetrain by minimizing vibrations, accommodating misalignment, isolating the shaft, and absorbing shock loads.

Boasting a robust polyurethane disc, this coupling absorbs shocks and vibrations while adjusting for misalignment due to engine or vessel movement. Additionally, the polyurethane is reinforced by metal compression straps that maintain constant pressure, enhancing the coupling's longevity.

In cases of shock loads, such as during gear changes or when the propeller hits an obstacle, the polyurethane disc sacrifices itself if overwhelmed, keeping the metal straps intact to ensure continued drive functionality.

Why Choose R&D Marine Flexible Shaft Couplings?