Patent ID: 8142108

Claim:
A riser installation method, comprising the steps of: providing a first vessel situated over a hydrocarbon well; supporting a hydrocarbon transfer duct from the first vessel by a first end that is attached to a lowering device on the first vessel; attaching a second end of the hydrocarbon duct to a second vessel, at a position near the first vessel; lowering the transfer duct via the lowering device; increasing the distance of the second vessel from the first vessel by sailing the second vessel in the direction of a third vessel, which is moored in a mooring position at a distance from the first vessel, while pulling the transfer duct until the second vessel is near the third vessel; contacting a section of the transfer duct with the sea bed at a position between the first and second ends of the transfer duct; displacing a second end of the transfer duct over a distance from the first vessel, seen in the length direction of the transfer duct, which is larger than the distance between the first vessel and the mooring position of the third vessel; returning the second end of the transfer duct to mooring position of the third vessel; and bringing the second end of the hydrocarbon transfer duct in fluid communication with the third vessel.