RENK tunnel gear unit, SHH type

The RENK tunnel gearboxes mounted in the propeller shaft – as free-standing, independent units – reduce the speed of the electric motor to the propeller speed in the electric operating state and accelerate the speed of the drive machine to match that of the PTO generator in the PTO (power take-off) operating state. RENK tunnel gearboxes – supplemented with an extremely flexible coupling – have already proven their durability and reliability in more than one hundred systems. The tunnel gearbox therefore enables increased efficiency in the PTO operating state at a low propeller speed (at approx. 60% of the nominal speed).
During maintenance, the system can be easily disengaged via a flexible coupling so that the propeller can be freely operated with the drive machine. Our gear units stand out for their compact and efficient design.


RENK tunnel gear unit, SHH type

Generation of electrical energy via drive machine with low speed

Reduced fuel costs thanks to efficient use of the drive machine

Shutdown of the diesel generator at sea

Savings on costs for maintenance and spare parts

Use of a standard high-speed generator

Installation of the tunnel gearbox behind the flywheel of the drive machine

Free-standing, independent gear unit system with integrated oil system

Flexible coupling protects the generator and the gearbox against torsional vibrations

Available with a horizontal offset, offset at an angle of 45° to the horizontal line, or with a vertical offset


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