RL-K 7500 Subsea Crane

Tuesday, February 19, 2013

During customer days at the production plant in Rostock in January 2013 Liebherr presented its new subsea crane, type RL-K 7500. With this new knuckle boom crane the company extends its range of offshore cranes for subsea operations.  The RL-K 7500 is able to lift up to 260t in the air and handle loads down to a water depth of 3,400m. The maximum rope diameter is 100mm, the maximum overturning moment of the crane is 75,000kNm. Depending on customers’ specifications, the boom configuration allows for working radii of up to 50 m.
One advantage of the crane’s knuckle boom is that loads can be lowered to the water surface with a short rope length between crane boom head and water line. 
Based on sophisticated Motion Reference Units (MRUs) the Active Heave Compensation system compensates this movement. In order to meet the high power demands of the AHC the hydraulic hybrid drive system Pactronic, originally developed for Liebherr mobile harbor cranes, was specially adapted for subsea applications. Pactronic is characterized by an additional energy storage device. A hydraulic accumulator supplements the fluid pump in delivering power to the system. It serves as a pressure storage reservoir incorporating a gas in conjunction with a hydraulic fluid. Energy is stored in this compressed gas to be released upon demand.
The AHC system is fully integrated in the Litronic system. One of its most important features is its self-learning function. It automatically recognizes the vessel’s motion and adjusts itself according to this information. Hence, the system does not need to be manually adjusted and is independent of weather conditions.  Up to 70% of the power required to operate the AHC system is currently obtained from Pactronic. This means that the hybrid drive system provides a maximum power of almost 4 MW.
In order to ensure optimized rope guidance, the crane has a patented horizontal winch shifting system that guarantees the ideal fleet angle of the rope under all load conditions in both hoisting and lowering operations. A further innovation is the vertical winch frame lifting system, which is also patented. Two hydraulic cylinders allow for the adjustment of the lifting height without moving the drum of the hoisting winch. Due to this design, wear of the main wire rope is minimized, intended to extend its service life and reduce life cycle costs. With the RL-K 7500 Liebherr offers an innovative crane concept for subsea applications.
The RL-K 7500 can be rated both as general purpose offshore crane and as heavy lift crane, being able to hoist loads weighing up to 300 t. It can thus be installed on board drill vessels and also heavy lift vessels.
Tobias.Fröhlich@Liebherr.com
www.Liebherr.com

 

(As published in the January/February 2013 edition of Marine Technologies - www.seadiscovery.com)


Offshore

Onshore Spending on the Cusp of Recovery?

DW’s recently released quarterly World Oilfield Services Market Forecast (OFS) and World Oilfield Equipment Market Forecast (OFE) continue to suggest 2016 will

US Offshore Lease Sale Yields $18 Mln in High Bids

Today’s U.S. oil and gas Lease Sale 248 garnered $18,067,020 in high bids for 24 tracts covering 138,240 acres in the Western Gulf of Mexico Planning Area, announced

Canada May Ask Far-offshore Drillers to Pay Extra

Canada may ask oil companies to contribute to the hundreds of millions of dollars or more the country has to pay to an international body if they drill far offshore,

Vessels

C-Job Designs Flettner Freighter for Switijnk

The Dutch shipping company family Switijnk has contracted C-Job Naval Architects to develop a Rotor Sail-equipped design to meet their specific loading and sailing profile.

Damen Trading Sale hits 500th Vessel

30 years and 500 vessels later, Damen Trading is just getting started. Damen Trading’s story begins in 1986, with Damen Shipyards Group responding to growing market demand for used vessels.

Matson Orders Two ConRo Ships from NASSCO

Matson Navigation Company, Inc., a subsidiary of container shipper Matson, Inc., has signed a contract with U.S. shipbuilder General Dynamics NASSCO to build two

Deck Machinery

ACE Winches Bags Order from Vard

Deck machinery specialist ACE Winches said it has been awarded a spooling contract with Vard Group AS for Norway’s largest construction vessel.   The scope of work includes the spooling of two 3,

 
 
Maritime Security Maritime Standards Navigation Offshore Oil Pipelines Port Authority Salvage Ship Electronics Shipbuilding / Vessel Construction Winch
rss | archive | history | articles | privacy | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.0901 sec (11 req/sec)