Coated pipelines carrying heated heavy oil - provided with multiple plastic coatings for corrosion protection and thermal insulation

摘要

Coating for corrosion-protection and the thermal insulation of channels or pipes primarily intended for conveying hot fluids, use a layer (I) for protection against corrosion, and a layer (II) for thermal insulation. The layer (I) is directly applied to the external surface of the pipe, whereas layer (II) consists of shells located and assembled round layer (I). An intermediate layer (Ia) is pref. used between layers (I) and (II) to permit the pipe to slide w.r.t. the shells during thermal expansion or contraction of the pipe, and an external layer (III) which is impermeable to moisture pref. surrounds the shells (II). Pref. coating materials are listed for use at up to 110 degrees C. Used e.g. on pipelines conveying heavy oil which must be heated so that it will flow. Effective protection and insulation of steel pipes carrying hot liqs. at up to 110 degrees C.