Diesel-Mechanic Four-Stroke Drive
Conventional tugs are designed for low-cost variants with lower maneuverability requirements. Low propeller speeds made possible by a reduction gearbox allow the use of larger propellers, which leads to a significant increase in the efficiency of the propulsion system and higher bollard pull. This classic propulsion design requires careful torsional vibration tuning by means of a highly flexible coupling both in the main drive train between the diesel engine and the main gearbox and in the high-speed PTO train.
Diesel-Mechanic Drive in Tug Boats
In order to achieve good maneuverability, tug boats are mostly fitted with steering-propellers. There are various steering-propeller systems on the market such as rudder-propellers in Z configuration or vertically-arranged steering-propellers. What these drive systems have in common is that the engine power and motor speed may be transmitted over a distance of several meters from the motor to the rudder-propeller’s gearbox. VULKAN Couplings provides the torsionally flexible coupling for the engine (mostly a highly elastic VULKARDAN E or RATO R type), as well as the shaft system.
Diesel–Mechanic Drive with short Shaftings
VULKAN offers a wide product portfolio for the special requirements of tugboats: In addition to high performance, the greatest possible maneuverability is essential for this type of vessel. To achieve this, tugs are usually equipped with rudder propellers. There are various systems of rudder propellers on the market, such as rudder propellers in Z-arrangement or vertically arranged rudder propellers. All these propulsion systems have in common that the engine power with engine speed is usually transmitted over a distance of several meters from the engine to the gearbox of the Rudderpropeller. For this purpose, VULKAN provides both, the torsionally flexible main coupling on the engine - usually of the highly flexible VULKARDAN E or RATO R type - and the shaft system. Whether a highly specialized coupling or shaft system for specific requirements - VULKAN has years of expertise in the field of high-performance drive systems and is committed to finding individual solutions that are optimally matched to the system environment.
Diesel-Electric Drive for Work Boats
Up to 7,000 operating hours per year, high performance requirements and the greatest possible maneuverability - these are the demands made of work boats.
To meet these demands, diesel-electric drive systems, in conjunction with steering propeller drives, are more and more frequently being used with these kinds of ships. In diesel engines drive generators, the generated energy is used to drive electric motors that in turn drive the corresponding rotatable steering propeller drive.
Diesel Hybrid Tug
As environmental demands like emission reduction in workboats increase, new propulsion concepts emerge in maritime markets. The background for that development includes the increasingly strict laws and regulations for watercraft operation in coastal waters, together with the increasing number of Emission Control Areas (ECA), which make alternative drive concepts necessary. Emission Control Areas are special navigation areas established by the International Maritime Organisation (IMO). Specific environmental guidelines apply to these zones, e.g. regarding emissions, so that special restrictions on sulphuroxide, nitrogen oxide and soot particle emissions exist in these areas.
Tugs are particularly affected by this as, by their very nature, they perform their work almost constantly close to the coast, and thus in ECAs located in many parts of the world. In addition to this challenging field of application, tugs usually share a certain load profile, perfectly suited for diesel-electric hybrid drivelines. Moreover, in the version currently favored by influentia engine manufacturers and designers, an electric motor between diesel and gearbox is switched onto the drive shaft. When full power e.g. for pulling is needed the diesel engine can run at rated power. In all other cases, when idling or at slow transit the diesel-engine can be decoupled and the generator/engine can supply the needed power.
For a flexible mounted engine as seen in the picture, VULKAN as system supplier can provide the whole spectrum of solutions for a comfortable and vibration reduced powertrain. Starting from 6- and 12-Degree-of-Freedom calculations as well as torsional vibration calculations and accoustics, VULKAN can supply engine- and gearbox-mounts, clutches and couplings optimized as one solution for the best system tuning.
Battery / Full Electric Drive
Up to 7,000 operating hours per year, high performance requirements and the greatest possible maneuverability - these are the demands made of work boats. In order to meet these demands, diesel-electric drive systems, in conjunction with steering propeller drives, are more and more frequently being used with these kinds of ships. In diesel engines drive generators, the generated energy is used to drive electric motors that in turn drive the corresponding rotatable steering propeller drive.