US 12,012,707 B2
Offshore platform deck removal method
Vincent George McCarthy, San Donato Milanese (IT)
Assigned to Saipem S.P.A, San Donato Milanese (IT)
Appl. No. 17/045,111
Filed by SAIPEM S.P.A., San Donato Milanese (IT)
PCT Filed Apr. 2, 2019, PCT No. PCT/IB2019/052684
§ 371(c)(1), (2) Date Oct. 2, 2020,
PCT Pub. No. WO2019/193491, PCT Pub. Date Oct. 10, 2019.
Claims priority of application No. 102018000004201 (IT), filed on Apr. 4, 2018.
Prior Publication US 2021/0148075 A1, May 20, 2021
Int. Cl. E02B 17/00 (2006.01); B63B 27/10 (2006.01); B63B 85/00 (2020.01); B66C 23/52 (2006.01)
CPC E02B 17/00 (2013.01) [B63B 27/10 (2013.01); B63B 85/00 (2020.01); B66C 23/52 (2013.01); E02B 2017/0052 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method for lifting a payload of an offshore platform, said offshore platform comprising at least one support structure supporting the payload, said payload comprising at least one main deck and at least one column directly connected to said at least one support structure, said at least one column supporting said at least one main deck, the method comprising:
welding at least one lower lifting device to a welding portion of said at least one column of the payload, said welding portion being located at a lower level in respect of said at least one main deck;
connecting a plurality of tension rods to the lower lifting device below said at least one main deck;
coupling at least one upper lifting device to the plurality of tension rods above said at least one main deck;
pre-tensioning said plurality of tension rods by adjusting rod length of at least some tension rods to apply a compressive action to said payload; and
separating at least one portion of said at least one column from said at least one support structure of the offshore platform for lifting said payload; and
lifting said payload using a crane vessel attached to said at least one lower lifting device and said at least one upper lifting device, wherein said lower at least one lower lifting device and said upper lifting device apply a compressive stress to said at least one column of said payload during the lifting.