Anchor line tensioning method

摘要

Method for mooring an offshore structure includes:
providing a mooring line having one end connected to the sea bed and a connector at a free end;lifting the free end onto a deck of an anchor line handling vessel;connecting on the anchor line handling vessel a chain tensioner with a connection side to the connector;providing a working chain having a short tensioning part and a long installation part into the entry side of the chain tensioner;holding a free end of the installation part while lowering the chain tensioner below water level;picking up a free end of a pendant attached to the offshore structure, and attaching it to the free end of the installation part in an interconnect position on the anchor line handling vessel;placing the interconnect position overboard;connecting a lifting cable on the anchor line handling vessel to the tensioning part below water level; andexerting an upward tensioning force on the tensioning chain part.

主权项

1. Anchor line installation method for mooring an offshore structure (1) to a mooring line (7,8,11) comprising the steps of:
providing a mooring line (11), with one end connected to a sea bed and comprising at a free end (13,15) a connector member (14, 22), lifting the free end (13,15) onto a deck of an anchor line handling vessel (12), connecting on the anchor line handling vessel a chain tensioner (17) with a connection side (18) to the connector member (14,22), providing a working chain (20) into the entry side (19) of the chain tensioner (17), the working chain having a tensioning chain part (28) and a installation chain part (21), the tensioning chain part being shorter than the installation chain part, holding a free end of the installation chain part (21) connected to the anchor line handling vessel while lowering the chain tensioner (17) below water level (46), picking up a free end of a pendant (32) attached on one end to the offshore structure that is to be moored, and attaching the free end of the pendant (32) to the free end of the installation chain part (21) in an interconnect position (52) on the anchor line handling vessel (12) and, placing the interconnect position (52) overboard from the anchor handling vessel (12), connecting a lifting cable (34) of a lifting device (33) on the anchor line handling vessel (12) to the tensioning chain part (28) below water level, and Exerting an upward tensioning force on the tensioning chain part (28) via the lifting cable (34).