Pressure regulation device in concentric tubings - comprises compressible elements esp. of syntactic foam

摘要

Device for pressure regulation in the fluid-filled sealed annular spaces between concentric tubings (14,20) of (esp. offshore) oil wells, comprises, in each annular space, several compressible elements (32) which define open passages (34,36) and which can be contracted by compression when the pressure in the annular spaces is increased by heating of the confined fluid. Pref. the elements (32) are made of a syntactic foam, e.g, polyurethane, polyethylene or polystyrene foam. ADVANTAGE - When fluid expansion occurs within the annular spaces, between the moment when the well head seals are installed and the moment when the well is put into prodn., the elements contract to maintain an equilibrium pressure supportable by the tubings.