Portugal's Lisnave, Setubal has recently carried out repairs on board EMAS' 5,096 grt self-elevating lift boat Lewek Leader. The main workscope for this project, which is due to last some 40 days, is to replace the lower part of one self-elevating leg, which has suffered cracking and will be replaced by new leg sections (four) which includes spud can with 10 feet.
The new leg, which will measure 97.50 m x 3.00 m, and spudcan was prefabricated in United States and installed at the Mitrena shipyard. The Lewek Leader is a self-elevating lift boat measuring 56.40 m x 44.20 m x 6.90 m classed by ABS. She is self-propelling and self-elevating, with a large deck area and high capacity cranes (two 181 tons at 9.10 m). The unit, which has accommodation for up to 160, is designed for use in shallow waters up to 65 m. Her propulsion machinery comprises three 1,100 kW azimuth thrusters, a 440 kW bow thruster.
Other general repair work carried out includes outside hull cleaning and painting, repairs to sea chests and grids, aft spud can/leg repairs, and lifeboat repairs. To enable this rig to be drydocked a special berth arrangement had to be undertaken. This involved preparation and installation of a special arrangement, with 6.40 m height, and temporary supports, with 18 m height, on the aft hull tubular structure. It also involved the heavy lift truck shifted to inside drydock using yard gantry crane 500 tons and then heavy (145 tons) spud can shifted and placed on top of heavy truck and transported to position and fitted to leg.
Lisnave has also recently completed general repairs to the 13,688 grt seismic research vessel Ramform Sovereign, which is owned by Norway's PGS. Since 1995 PGS has taken the seismic vessels operation to a new level with the application of the Ramform design with its singular delta shaped design.
The Ramform Sovereign was built in 2008 in Langsten, Norway and has recently successfully undergone her first ever drydocking operation in Lisnave, lasting some 26 days. The shipyard performed both marine and technical repair operations, including maintenance and refurbishment. One of the main aspects of the repair involved Rolls-Royce streamer winches, which underwent structural steel upgrade to a bigger tonnage capacity. Work also included installation of new entrance for engine room as well as new drop gates on Deck 4. Major shaft lines and rudder repairs were also performed together with Wärtsilä. Also carried out was substantial hull surface treatment, including a full underwater blasting process carried out, in its majority with robotic ultra-jet hydro-blasting equipment.
The shipyard provides a complete set of services to seismic vessel owners', along with complete carnage capacity and large storage/working areas available. Necessarily care is taken during off/on-loading streamer cables and lead-ins and its transportation and storage, thus supporting Owner with the necessary facilities for the maintenance and upgrading of such essential equipment.