Tunnel Gearboxes
Tunnel gearboxes are specially engineered to provide power take off (PTO) for vessels with 2-stroke engines. It does so by connecting to the slow turning propeller shaft and increasing the speed to generator speed (up to 1800 rpm) thus allowing for a more energy efficient solution compared to the traditional in-line generator. This way you can optimize vessel operations, reduce costs, and enhance sustainability.
Key Features and Benefits
Power Take-Off (PTO) and Power Take-Home (PTH)
The tunnelgearbox allows for both PTO and PTI in the propulsion line of a 2-stroke engine. If you combine the tunnel gearbox with a shaft clutch the tunnel gearbox also allows for PTH. The PTH functionality ensures propulsion resilience by enabling the use of alternative power sources during main engine downtime.
Fuel Savings
By utilizing the main engine’s high efficiency to generate auxiliary power, tunnel gearboxes significantly reduce fuel consumption. This leads to substantial cost savings and supports greener maritime operations.
Cost Saving
The tunnel gearbox allows the auxiliary generators to be shut down during sea voyages. This not only cuts the fuel costs, but also significantly reduces maintenance needs on the aux. generators.
Enhanced Efficiency
By covering the hotel load by using PTO from the highly efficient main engine instead of the auxiliary generators there is a significant increase in overall efficiency. What differentiates the tunnel gearbox from the slow-turning in-line generators is that the tunnel gearbox allows us to use a smaller, cheaper and more efficient generator. The in-line generator needs to consider the propeller shaft movements which results in them having to have a larger air gap between the rotor and stator, thus making them less efficient. In the tunnel gearbox the shaft movement is absorbed in the highly elastic coupling allowing the use of a generator with a much smaller airgap, hence an overall more efficient solution.
Applications and Advantages
Tunnel gearboxes are indispensable for vessels equipped with slow-speed two-stroke engines. They are particularly beneficial for optimizing energy use, cutting operational costs, and enhancing reliability in commercial shipping, tankers, and other large maritime vessels.
With features like PTO, PTH, and the ability to improve fuel efficiency, tunnel gearboxes are a cornerstone of sustainable maritime engineering. They provide a reliable, cost-effective energy solution while supporting the continuous, efficient operation of critical vessel systems.
