Subsea pipeline insulation

Abstract

A deep sea insulated pipeline comprises an inner pipe which is encased lengthwise by an insulating core. The insulating core comprises macrospheres surrounded by syntactic foam that includes a semi-rigid resin binder and microspheres. The semi-rigid resin binder reinforces the macrospheres to provide sufficient strength to withstand the hydrostatic pressure at depths in excess of several thousand feet of water, and is yet flexible enough to accommodate bending associated with deep sea pipe laying operations. The deep sea insulated pipeline may also include a protective outer casing. The inner pipe extends through and cooperates with the outer casing to define an annulus chamber containing the insulating core. The outer casing may be a plastic pipe. In a preferred embodiment the semi-rigid resin binder includes Bisphenol-A epoxy resin, an anhydride curing agent, and a flexibilizer.

Dependencies are inferred from the claim text.