Offshore liquid transfer system - through axially movable pipe inside stationary pipe on sea bed

摘要

A system for the transfer of a fluid from an offshore prodn. plant to a transfer tower for transhipment to tankers, esp. for liquefied gases (natural gas) from an offshore platform with a liquefying plant, uses double pipes on the sea bed to connect the two points. A stationary outer pipe, sheathed in concrete or ferro-concrete, terminates in the base structures of offshore platform and transfer tower. An inner pipe is axially movable and is joined by swivels to the vertical pipes to platform and tower surface. An empty stationary pipe extends on the sea bed from one of the stations to the same length as the connecting pipe. This allows the inner pipe to be pulled out for inspection or repair. It protects the insulated inner pipe against the hydrostatic pressure and allows a free thermal contraction and elongation.