Crane swop shop

The demands that deepwater operations place on deck-mounted cranes has forced manufacturers to offer a wider choice of cranes.

Arne Riple, vice president of sales and marketing at TTS Marine told The Motor Ship; “The owners that we work with in these instances are quite particular regarding their crane specifications. We are unable to meet the requirements for a general crane type, within reasonable cost levels, whilst maintaining only one design.” Some operators have even opted to keep spare cranes onboard or on other vessels, available to swop when the need arises. The swop is made easy by the use of cranes using a common pedestal. Ostensjo is one operator that has gone down this route.

Riple explains; “For most of these cranes, we are talking large winches for seabed operation in combination with an alternative crane with much smaller load capacity and winch capacity.” He says that depending on the contract of operation for the ship, the operators will demand a detailed crane specification, and the possibility of swapping these cranes between their own fleet may prove advantageous.

TTS Marine has provided Farstad with another solution involving a rail-mounted crane that is able to lift from three different positions along the length of the vessel. Riple explains that the three point limitation is due to the need for fixed support at each working location. The rail crane is moved from one position to the next with a chain, and secured in position for operation. “We find that three locations are quite sufficient to serve all areas of the ship?s deck,” says Riple. He told The Motor Ship; “To have a crane working unfettered and without constraints along the ship would make this more like a rolling gantry crane and would, for this purpose, be more costly without giving the additional benefit to cover this cost.” TTS is talking to a number of other operators about this crane type.

Another order for a crane for the Grampian Surveyor, built by Astilleros Balenciaga for Northstar Shipping in the UK, sees TTS using a folding jib crane to reduce the pendulum effect, and gives more flexibility. The cranes, which will be used for operation of a ROV and seabed operation up to 2,000m, is equipped with an electronic load sensing system, depth monitoring system and constant tension

capability.

More recently, TTS successfully secured a contract to supply a bespoke package of offshore and service cranes on a specialised oceanographic research vessel the Pourquoi Pas?. The vessel is being built by ALSTOM Leroux Naval shipyard in Brittany for the French Ifremer Institute.

Alstom claims that the vessel, due for delivery at the beginning of 2005, is equipped to sail in all seas and will be fitted to achieve any mission in the fields of deep-sea, coastal oceanographic and hydrographic research. The 105m Pourquoi Pas? will be capable of carrying Ifremer?s large scale equipment, such as the manned submersible Nautile, the remotely controlled submersible Victor 6000, or new launches of the French Navy?s Hydrographic and Oceanographic Department (SHOM). The civilian ship will be used 200 days a year by Ifremer and 150 days by the French Navy.