A method protects a field joint of a pipeline, where chamfered edges of thermally-insulating parent coatings on conjoined pipe lengths are in mutual opposition about a longitudinally-extending gap. The method includes manufacturing an hourglass-shaped inner layer around the pipe lengths, which layer may be moulded. The inner layer extends longitudinally along the gap between the chamfered edges and at least partially overlies the chamfered edges. A thermally-insulating solid insert is assembled from two or more parts to lie in the gap surrounding the inner layer, and pressure is applied radially inwardly from the insert to the inner layer. An outer layer of molten material is manufactured around the insert to form a watertight barrier and to form one or more melted interfaces with the inner layer. Corresponding field joint arrangements are also disclosed.

A composite article has increased pull-off strength and includes a first layer including a low surface energy polymer, a poly(meth)acrylate layer, and an epoxide layer. The poly(meth)acrylate layer is disposed on and in direct contact with the first layer. Moreover, the poly(meth)acrylate layer includes a poly(meth)acrylate that includes the reaction product of at least one (meth)acrylate that is polymerized in the presence of an organoborane initiator. The epoxide layer is disposed on and in direct contact with the poly(meth)acrylate layer. The epoxide layer includes an epoxide. The composite article has a pull-off strength of greater than zero pli measured using ASTM D4541.

A composite article has increased pull-off strength and includes a first layer including a low surface energy polymer, a poly(meth)acrylate layer, and an epoxide layer. The poly(meth)acrylate layer is disposed on and in direct contact with the first layer. Moreover, the poly(meth)acrylate layer includes a poly(meth)acrylate that includes the reaction product of at least one (meth)acrylate that is polymerized in the presence of an organoborane initiator. The epoxide layer is disposed on and in direct contact with the poly(meth)acrylate layer. The epoxide layer includes an epoxide. The composite article has a pull-off strength of greater than zero pli measured using ASTM D4541.

An insulating insert is positioned around a field joint of a pipeline to insulate the field joint. The insert comprises a longitudinal series of annular or part-annular filler segments of insulating material, curved about a longitudinal axis, that are each joined to one or more adjacent segments of the series by at least one link. The links may be webs, rods or articulated links. The links are flexible relative to the segments to facilitate bending of the insert along its length by enabling relative angular displacement between adjacent segments of the series.

An insulating insert is positioned around a field joint of a pipeline to insulate the field joint. The insert comprises a longitudinal series of annular or part-annular filler segments of insulating material, curved about a longitudinal axis, that are each joined to one or more adjacent segments of the series by at least one link. The links may be webs, rods or articulated links. The links are flexible relative to the segments to facilitate bending of the insert along its length by enabling relative angular displacement between adjacent segments of the series.

A composite article is formed by disposing a poly(meth)acrylate layer, formed as the reaction product of at least one acrylate that is polymerized in the presence of an organoborane initiator, on and in direct contact with a low surface energy polymer layer, disposing an epoxide layer on and in direct contact with said poly(meth)acrylate layer, and disposing a hydrolytically resistant layer on and in direct contact with said epoxide layer. The hydrolytically resistant layer is a hydrolytically resistant polyurethane elastomer that is the reaction product of an aliphatic isocyanate component and an isocyanate-reactive component that retains at least 90% of its initial tensile strength after submersion in standardized seawater for 24 weeks. The isocyanate-reactive component is a hydroxyl-functional polymer having an average hydroxy functionality ranging from 2 to 3, wherein the hydroxyl-functional polymer is a dimer diol, a trimer triol, or a combination thereof.

A composite article is formed by disposing a poly(meth)acrylate layer, formed as the reaction product of at least one acrylate that is polymerized in the presence of an organoborane initiator, on and in direct contact with a low surface energy polymer layer, disposing an epoxide layer on and in direct contact with said poly(meth)acrylate layer, and disposing a hydrolytically resistant layer on and in direct contact with said epoxide layer. The hydrolytically resistant layer is a hydrolytically resistant polyurethane elastomer that is the reaction product of an aliphatic isocyanate component and an isocyanate-reactive component that retains at least 90% of its initial tensile strength after submersion in standardized seawater for 24 weeks. The isocyanate-reactive component is a hydroxyl-functional polymer having an average hydroxy functionality ranging from 2 to 3, wherein the hydroxyl-functional polymer is a dimer diol, a trimer triol, or a combination thereof.

A composite article includes a low surface energy polymer layer, a poly(meth)acrylate layer, an epoxide layer, and a hydrolytically resistant layer. The poly(meth)acrylate layer is disposed on and in direct contact with the low surface energy polymer layer and includes the reaction product of at least one acrylate that is polymerized in the presence of an organoborane initiator, such that the poly(meth)acrylate includes boron. The epoxide layer is disposed on and in direct contact with the poly(meth)acrylate layer. The hydrolytically resistant layer is disposed on and in direct contact with the epoxide and is the reaction product of an isocyanate component and an isocyanate-reactive component reacted in the presence of a curing agent. The isocyanate-reactive component includes a polydiene polyol and the curing agent crosslinks the carbon-carbon double bonds of the polydiene polyol.

A composite article includes a low surface energy polymer layer, a poly(meth)acrylate layer, an epoxide layer, and a hydrolytically resistant layer. The poly(meth)acrylate layer is disposed on and in direct contact with the low surface energy polymer layer and includes the reaction product of at least one acrylate that is polymerized in the presence of an organoborane initiator, such that the poly(meth)acrylate includes boron. The epoxide layer is disposed on and in direct contact with the poly(meth)acrylate layer. The hydrolytically resistant layer is disposed on and in direct contact with the epoxide and is the reaction product of an isocyanate component and an isocyanate-reactive component reacted in the presence of a curing agent. The isocyanate-reactive component includes a polydiene polyol and the curing agent crosslinks the carbon-carbon double bonds of the polydiene polyol.

A method of connecting together two unit elements (4, 4) of a fluid transport pipe, each unit pipe element being covered in an outer insulating coating (6, 6) made of a thermoplastic material, with the exception of an end portion that does not have an outer insulating coating. The method includes: a step of welding together two abutting unit pipe elements; a step of positioning an annular sleeve (14) around a cut-back and in part around the outer insulating coatings of the two unit pipe elements, the sleeve being made of a thermoplastic material; a step of fastening the sleeve in sealed manner by weld bonding on the outer insulating coatings; and a step of applying an external pressure on the sleeve to enable it to be deformed elastically and match the shape of the respective end portions of the two unit pipe elements.