The Hexaflex-Blue is a new range of shaft couplings available from Techdrives for marine applications.  Designed for small to medium propulsion drives, also auxiliary drives and bow thrusters, Hexaflex-Blue combines high misalignment capacity with vibration damping to achieve a smoother transmission and longer life of the drive components.  Eight sizes are available with rated torques from 55 to 1760Nm and coupling dimensions can be customised to fit between the gearbox and driven shaft.  The maintenance free design is already proven on leisure and military applications.

At the heart of the Hexaflex-Blue coupling is a synthetic rubber flexible element with six bolt holes, three to connect to the driving side and three to the driven side.  Between each bolt hole run loops of strengthening cord which maintain the flexibility yet introduce toughness.  A long life is assured by the safety factor between rated torque and breaking torque which is typically ten times.  Another advantage of the rubber construction is the ability to absorb vibrations from the motor resulting in smoother and quieter transmission of torque.  The flexible element is bolted on one side to an adaptor for the gearbox flywheel, and on the other to a clamp hub.  Metal parts are stainless steel to eliminate corrosion and the complete assembly is backlash free which contributes to the long life when torque oscillations are present. The gearbox adaptor can be supplied with customised dimensions, for example Yanmar and ZF Marine adaptors are available today.

Hexaflex-Blue couplings are easy to mount with only radial access needed – the gearbox and shaft do not need to be moved axially.  The ability to accept a combination of radial and axial misalignment whilst at the same time absorbing torsional vibration leads to longer life for the components in the drivetrain.  Not to mention a smoother and more comfortable environment for those on board.  More information is available on www.techdrives.co.uk.