Vulkan Couplings of Germany has recently been involved with two contrasting marine projects. The company, headquartered in Herne, Germany, provides couplings for a variety of applications including ships’ main and auxiliary drives, boat drives, generator drives and drives for industrial application and for rail vehicles.
Recently, it supplied couplings for the suction dredger Gateway, which was launched at the IHC Merwede Offshore and Marine shipyard in Hardinxveld-Giessendam in the Netherlands. The vessel was completed for Dutch dredging, maritime infrastructure and services company Royal Boskalis Westminster N.V.
The Gateway is 137 m long, 28 m wide and has a hold capacity for dredged material of 12 000 m3. The ship was designed by IHC Merwede with the focus on keeping the ship’s
weight to a minimum with a concurrent maximum hold capacity. The Boskalis suction dredger has a suction pipe with an underwater pump, which can suck at a depth reaching 62 m. In the dredger pump’s gearbox generators, three RATO-R couplings from Vulkan Couplings are used. Vulkan said the elastic couplings are developed specially
for use in installations needing high torsional flexibility and good misalignment capacities.
The Gateway, which is capable of 15.4 knots, is driven by two Wärtsilä 12V32 engines with a power output of 6 MW. Vulkan Couplings supplied two RATO-S couplings for these engines. In November 2007, IHC Merwede and Boskalis signed a contract for two identical dredgers. The Gateway’s sister ship is presently being built by IHC Dredgers in Kinderdijkn, Netherlands.
Vulkan will also supply the couplings cited above for this ship. Elsewhere, products from Vulkan Couplings and Vulkan DMR have reduced noise and vibration to virtually zero on the mega-yacht Silver Cloud built by Abeking and Rasmussen at its yard at Lemwerder, Germany.
The yard incorporated the SWATH concept from pilot boats, which ensures good ship stability in heavy seas, into the build of the yacht. SWATH stands for “Small Waterplain Area Twin Hull” and has been transposed for the first time into the Silver Cloud. The 41m long yacht has a steel hull and an aluminium superstructure.
The steel hull consists primarily of two floating bodies with a diameter of approximately 2 m, which are connected to each other through the first between deck. A complete drive unit is housed in each floating body. For each drive train, an 820 kW Caterpillar C32 engine is used with a ZF-3310 gearbox via a Vulkardan-E E5411 coupling. The drive motor is mounted opposite the gearbox on a joint frame using Vulkan-DMR T60 mountings.
Vulkan said that for optimum noise and vibration dampening, the joint base frame is in turn mounted on Vulkan-DMR T35 mountings. The gearbox output flange is connected to the propeller via the thrust bearing using a combination of Vulkan Propflex couplings with a Vulkan composite shaft for weight reduction. Using the Propflex couplings, the noise paths from the drive unit to the ship’s structure are successfully blocked, said Vulkan.
In each floating body, a Caterpillar C9 generator provides onboard power. The maximum ship speed is 14 knots.