Sealed and waterproof seabed heat-preservation pipe

Abstract

The invention discloses a sealed and waterproof seabed heat-preservation pipe, which comprises a steel pipe, wherein the outer surface of the steel pipe is provided with a corrosion-resisting layer, the outer surface of the corrosion-resisting layer is provided with a heat-preservation layer, the outer surface of the heat-preservation layer is stuck with a covering protection layer, the covering protection layer is formed by a polyurethane elastomer, the polyurethane elastomer covering protection layer is stuck on the heat-preservation layer and the corrosion-resisting layer through a polyurethane base coating agent, the two ends of the polyurethane elastomer covering protection layer are respectively overlaid with the corrosion-resisting layer, the heat-preservation layer is sealed on the steel pipe, and the outer surface of the polyurethane elastomer covering protection layer is provided with a weighting layer. According to the invention, the sticking performance between the polyurethane elastomer covering protection layer and a polyurethane foam heat-preservation layer and the sticking performance between the polyurethane elastomer covering protection and an FBE (Fusion Bonded Epoxy) corrosion-resisting layer are good, the sticking strength is larger than 10 MPa, the sea water can penetrate through the sticking position of the polyurethane elastomer covering protection layer and the polyurethane foam heat-preservation layer and the sticking position of the polyurethane elastomer covering protection and the FBE corrosion-resisting layer, so that the foam heat-preservation layer can be better protected, the waterproof property and the sealability are good, the pressure resisting strength is high, and the heat-preservation effect is good.

Description

technical field [0001] The invention relates to a transportation pipeline, in particular to a sealed and waterproof seabed heat preservation pipe used for conveying crude oil or natural gas medium in the ocean deep water environment. Background technique [0002] During the development of offshore oil and gas fields, crude oil is mostly transported through pipelines, and the outlet temperature of crude oil is relatively high, while the temperature of seawater is relatively low. In order to avoid waxing and condensate blocking pipelines during crude oil transportation, it is necessary to insulate the pipelines. The traditional double-steel insulation is to fill the middle of the two-layer steel pipe with a polyurethane foam layer. However, this insulation method consumes a lot of steel, takes a long time to weld offshore nodes, and lays pipes slowly. The overall cost is high. The single-steel insulation and counterweight tube structure that appeared later was: "tube + FBE ant...

AI Technical Summary

Problems solved by technology

[0003] The bonding strength between the waterproof cap and the outer protective layer of the above-mentioned insulation material and the FBE anti-corrosion layer is not high enough, and it is easy to peel off from the protective layer under a certain hydrostatic pressure, and water will penetrate into the insulation layer

In addition, there is a certain gap between the waterproof cap and the insulation layer, which will break and leak under a certain hydrostatic pressure, making the insulation invalid

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