FR2381166A1 - Charging petroleum from offshore well to ship - using a flexible pipe extended by a caisson lifted at optimum rate by ship's hoist, avoiding damage - Google Patents

Abstract

An appts. for collecting petroleum prods. from sub-marine wells incorporates a submerged structure, a caisson and a flexible pipe. The submerged structure is fixed and in communication with a well-head. The caisson is mobile and can be moved between a rest position on the submerged structure and a petroleum charging position at the surface of the water. The flexible pipe connects the submerged structure and the movable caisson. The caisson has a housing at its upper part in which are a float and a chain. The chain is coiled within the housing. Its ends are fixed to the housing and to the float respectively. The float is retained in the housing by a mechanism which allows the float to be liberated when it is actuated remotely. The length of the chain is about equal to the depth of immersion of the structure. When the float is liberated it rises to the surface taking the chain with it. The float has a hitch by which it can be picked up by a hoist on the ship. The hoist can then lift the mobile caisson carrying the end of the flexible pipe. Problems associated with existing equipments are avoided; these include rapid rising of the mobile caisson causing damage, and the fact that the flexible pipe hangs relatively slack and is subjected to the swell or to currents.