Tight fit for Grane process module

Rigging Management Systems has been serving the heavy-lift needs of the industry for over 20 years with its proven push-up system. The system uses from two to eight masts and is operated from ground level without placing any personnel on the rigging. A positive locking mechanism ensures that the load remains stable even if a hydraulic failure occurs.

Last December, an indoor lift for the Halfdan platform was performed at the Bladt yard in Aalborg, Denmark. The lift involved a 1,000-ton deck, which was lifted so that the legs could be installed underneath. One day was spent lifting the deck - it was subsequently suspended for 10 days while the legs were welded in place. The assembly was then lifted so it could be moved onto a barge for load-out. The Halfdan platform was later installed in the Danish sector of the North Sea.

Close scheduling

While the Halfdan lift ended a good year, 2002 continued with a close schedule. During early March the equipment was moved to Sweden's Scanraff refinery for the installation of a propane filter column. This 90-m high system weighed 350 tons and was lifted in very heavy weather. Two masts were used to lift the column while a single crane held the column's base for control.

In mid-March, the equipment was shipped to Kværner in Egersund, Norway, to lift the 1,800-ton CO-1 module as part of the larger C10 process module for Norsk Hydro's Grane project. The module was very stiff and required equalizing two of the corners by pressure connecting two of the lifting jacks. This effectively produced a three-point lift. During the same week a 1,500-ton module was being lifted for Aker Kværner, Stord, for the Grane project using the same equipment.

Rigging Management Systems operates lifting systems rated for 600-ton/mast and 750-ton/mast. Recently its Norwegian partner, TransRig AS, put a 1,000-ton/mast push-up system into routine use. This system has already been used twice, lifting two modules at Aker Kværner, Stord.

RMS is developing stronger jacks with a likely limit of 1,500 ton/mast. Eight masts will provide a lifting capacity of 12,000 tons.

For more information, contact: Jan-Erik Andersson, Rigging Management Systems. Tel: +46 500 43 70 70, fax: +46 500 43 67 40, email: [email protected].

The jacking system operates in "push-up"mode. It includes a series of vertical masts used to support the body to be lifted, hydraulic jacks synchronized to lift as a unit, and support pins (also known as bullets) in 1 m lengths that are inserted after each lift. The system is always in compression and is maintained in vertical alignment. Each mast is extendable in 6 m segments so that high lifts are possible.