RENK AG, Augsburg, is known throughout the world as a supplier of sophisticated gear sets for navy ships. A RENK recipe for success: Professional support of shipyards and Navies with technical innovations in both the development and the search for optimiza-tion potential, accomplished with continuous improvement of production tools.
By beginning of this year, RENK was successful in gaining a significant milestone to their activities in the US: The 20 Littoral Combat Ships ordered by the US Navy as part of the LCS program will be equipped with RENK marine propulsion gears.
Two shipbuilding teams were competing over years, and were awarded finally with 10 vessels each. The Lockheed Martin concept provides a 115 meter long monohull built out of steel, whereas the Austal team counts on an aluminum hull trimaran at 127 meter length. Both frigate designs are waterjet driven exceeding 40 knots speed by far, and will be serving for protection in littoral water areas.
Both LCS flight zero prototypes, the “ USS Freedom ” (Lockheed Martin) and the “ USS Independence ” (Austal) were commissioned to the US Navy in 2009. The Austal trima-ran propulsion system contains RENK main reduction gears since the beginning, where the Navy was able to experience already the reliability and modern technique of RENK gears. Now, in view of the award addition to the Lockheed Martin LCS frigates, RENK was nominated as long term main gear supplier for the entire LCS fleet.
The order provides for deliveries of two gear sets a year to both teams each in parallel from 2012 onwards during a period of five years. The drive concepts are significantly different. With the Lockheed Martin mono-hull, the combined power at max. 85 MW of two gas turbines and two diesel engines is being distributed via two in parallel arranged CODAG propulsion systems to four water jets. Austal’s trimaran is also combining four water jets, however, those are being driven singularly from two gas turbines and two diesel engines, at a total of 62 MW power.
Naturally, both ship propulsion designs have in common the renowned gear technology of RENK. Refined adjustment of single gear ratios within a reduction gear component between input and output and further design details ensures a lowest weight possible. By double helical gears, reliable torque transmission at lowest noise radiation is achieved, a must for such ship categories.
The vessels will be built at three shipyards in the United States. Austal would go for an entirely own production, and will nearly double the capacity of its yard in Mobile, AL. Lockheed Martin distributes the construction to two shipyards, the capacities of which are supposed to be adjusted significantly in similar ways.
Based on the experience with current orders to the US government – for example the delivery of CODAG main reduction gears to the US Coast Guard National Security Program (NSC) – RENK has established an organizational structure to ensure com-pliance with complex regulations of the US government, including appropriate adminis-tration and ITAR control. The reduction gears will be designed, manufactured and tested at 100 % in Germany, prior to their travel to the single shipyards in US.
Thanks to this order, RENK is now able to establish its outstanding gear technology for frigate main propulsion gears with the US Navy in a broad range. Together with its expe-rience in individual drive train solutions aboard fleets of 35 Navies worldwide, RENK’s position as leading gear supplier in this sophisticated field of application is being signifi-cantly increased. [mappress] Source: RENK, May 20, 2011;