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)

Maritime Reporter March 2015 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Offshore

China Unveils Action Plan on Maritime Silk Road

China has unveiled the principles, framework, and cooperation priorities and mechanisms in its Maritime Silk Road initiative in a bid to enhance regional connectivity

JV Wins $2bln Freeport LNG Contract in US

A joint venture (JV) between CB&I, Chiyoda International and Zachry Industrial has won a contract worth over $2bn from FLNG Liquefaction 3 for a liquefied natural

Feds Delay LNG’s Port Ambrose Application

The US Coast Guard and the US Maritime Administration (MARAD) have temporarily suspended their review of the proposed Port Ambrose deep-water LNG import terminal.

Vessels

Gulf Bridge Express Service to End

The Gulf Bridge Express Service will shortly be terminated with the last roundtrip voyage being MV Saint Nikolaos voyage 00008S, ETA New Orleans on April 22, 2015.

Obangame Express 2015 Concludes in the Gulf of Guinea

Maritime forces from Gulf of Guinea nations, Europe, South America, and the United States and several regional and international organizations concluded the multinational maritime exercise,

Scandlines Ferry Back in Service by End June

The damaged Scandlines ferry M/V Prinsesse Benedikte is being repaired at the Polish shipyard Remontowa and is expected to be ready before the end of June 2015.

Deck Machinery

SAL Heavy Lift Performs Offshore Windfarm Work

MV Lone proves as project platform for Wikinger wind farm   SAL Heavy Lift informs it has completed the second phase of the Wikinger Pile Testing Campaign with DP II Class vessel MV Lone.

Liebherr Opens African Maritime Hub

Liebherr Maritime Cranes celebrated the grand opening of the new sales and service center in Durban, South Africa. The new African maritime hub was opened by a

Motion Compensation Crane Delivered

Barge Master has delivered its first Barge Master T40 (BM-T40) motion compensated knuckle boom crane, the company announced.   The BM-T40, installed on Wagenborg’s

 
 
Maritime Contracts Maritime Security Naval Architecture Offshore Oil Pipelines Pod Propulsion Salvage Ship Electronics Ship Repair Sonar
rss | archive | history | articles | privacy | terms and conditions | 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: 0.2383 sec (4 req/sec)