AN UNBONDED FLEXIBLE ARMORED RISER PIPE

摘要

An unbonded flexible armored pipe for transportation of fluids. The pipe has a center axis and a length and includes a carcass and an innermost sealing sheath with an inner surface surrounding the carcass. The carcass includes at least one elongate armor element wound to surround the center axis with a winding angle to the center axis defining a winding direction and a supporting surface facing towards the inner surface of the innermost sealing sheath and with a supporting surface radius Sr. The supporting surface includes a primary surface area and a plurality of restraining regions in the form of orifices in and/or protuberances and/or indentations from the primary surface area, wherein the restraining regions each have a length determined along the winding direction of the elongate armor element which is up to about Sr times &Pgr;.