Sakhalin: Offshore Heavy Lift Refit
Large-scale conversion project on offshore platform Molikpaq operated by Sakhalin Energy.
While the refit of heavy lift capacity onboard an offshore rig might sound mundane, Liebherr’s project to replace and modernize cranes on the offshore platform Molikpaq operated by Sakhalin Energy, a unit subjected to some of the world’s harshest conditions, is anything but mundane.
The modernization project on Sakhalin Energy’s offshore platform off the Russian island of Sakhalin includes two ram luffing offshore cranes, type RL 1500 that are going to be completely renewed. An existing crane, type BOS 1900 will be upgraded with the same generation control system as the RL 1500.
Molikpaq operated by Sakhalin Energy was the first Russian offshore oil production platfor, with commercial oil production from the platform starting in 1999. Since December 2008 oil from the platform streams through the trans-Sakhalin pipeline system to the oil export terminal of the Prigorodnoye production complex. After two decades of continuous operation, the existing three Liebherr offshore cranes needed to be renewed.
Liebherr was tapped to completely replace two of the offshore cranes while the third device will be modernized for further operation, a unique and demanding project which involved weveral Liebherr companies. The contract drafting and signing were carried out by Liebherr-Russia OOO (Russia). Liebherr-MCCtec Rostock Gmbh (Germany) is responsible for the operational refurbishment of the platform. Liebherr-Werk Biberach GmbH (Germany) participates in the conversion with a tower crane which is used as a support crane for lifting large components. Since the start of the project in 2016, more than 6,000 planning hours have already been invested in the project.
To date, the replacement of the first crane (Liebherr BOS) with a new Liebherr RL 1500 has already been completed in the autumn 2018.
In order to be able to move large parts on the platform, Liebherr installed a tower crane of the type 230 HC-L 8/16 Litronic to be used as a support crane. In addition, a special sliding system was designed and built by Liebherr´s customer service team to move particularly heavy components and modules over the platform. Extreme weather conditions and limited space on the platform are primary challenges to the project, which is scheduled for completion by the end of 2020.
The second phase, the modernization of the existing BOS 1900, has also already been finished. The main reasons which triggered this modernization was to have the same software and handling for the crane operators as the two new RL 1500.
The third phase will include the installation of the second ram luffing crane until the end of 2019. Both RL 1500 cranes are characterized by a cylinder luffing box boom design and a diesel-hydraulic driven main engine. Considering the project specifics, the cranes can handle loads up to 65 tonnes, or 25 tonnes more than the standard lifting capacity of Liebherr RL 1500. This customized solution has been ensured by providing a three fall reeving. Equipped with a main and an auxiliary hoist the RL cranes have a maximum outreach of 42.6 meters.
Considering the geographic locale of the rig and the environmental conditions in which it operates, the cranes are equipped with an arctic temperature package which allows operation down to -36°C.