A heat transfer system having a heat transfer fluid circulation loop of a first fluid is disclosed. A conduit is disposed in the fluid circulation loop with an inner surface in contact with the first fluid at a first pressure. An outer surface of the first conduit is in contact with a second fluid at a second pressure that is 69 kPa to 13771 kPa (10 psi to 2000 psi) higher than the first pressure. The conduit also includes a polyurea coating on its outer surface.

A method of protecting a layered coating on a length of pipe for subsea use includes applying an edge finisher to the coating to encase an edge of the coating by fusing the edge finisher with the coating or by molding the edge finisher at an edge of the coating. Where the coating and the edge finisher are of thermoplastics such as PP, fusing can be achieved by injection molding the edge finisher or by welding a discrete edge finisher component to the edge of the coating. Mirror welding may be employed for this purpose, with a hot plate being interposed between the edge of the coating and the edge finisher.

A method of joining together liner sections within a polymer-lined pipe energises an induction coil inside the pipe to spot-heat part of a circumferential interface between the liner sections. This melts and fuses the polymer material locally. The induction coil is then moved along the interface to heat other parts of the interface successively above the melting temperature. An apparatus for performing the method has a power supply for energising the induction coil and a drive system for moving the energised induction coil relative to a body of the apparatus. The apparatus may be configured as a carriage that is movable along the pipe.

A heat-shrink sleeve is provided for covering a pipe joint formed between two pipes that are coupled to one another to form a tube. The heat-shrink sleeve comprises a heat-shrinkable material that is configured to conform to the first and second pipes when heated to cover the pipe joint.

An applicator machine and a process for heating and coating a section of pipeline. The applicator machine includes a frame configured to rotate about a section of pipeline to be heated and coated, rotating means operable to rotate the frame, and coating material applicators induction coils and radiant heaters mounted on the frame and rotatable therewith. The induction coil is configured to heat a section of pipeline adjacent to the induction coil to a coating material application temperature. The radiant heaters are configured to heat factory-applied coatings. Each coating material applicator sprays coating material through an aperture in a respective induction coil. The applicator includes an enclosure configured to surround a section of pipeline and provision for evacuating and collecting waste coating material. The coating material applicator may be configured to spray powder coating material, such as fusion bonded epoxy powder material and/or chemically modified polypropylene powder material.

A method for forming a high temperature field joint between two insulated pipe sections, and an insulated conduit having a low temperature field joint. The conduit comprises a steel pipe with a corrosion protection coating and a pipe insulation layer comprising a polymer composition having thermal conductivity of less than about 0.40 W/mk, and/or heat resistance to continuous operating temperatures from about 150° C. to above about 205° C. After a circumferential weld joint is formed between the two pipes, a first field joint insulation layer is applied over the joint area, the first field joint insulation layer comprises a polymer composition having heat resistance to continuous operating temperatures from about 150° C. to above about 205° C.

A mold for coating a pipeline section with molten coating material from an injection molding machine, wherein the mold comprises a shell of impervious material reinforced by an exoskeleton of non-distensible material. An assembly for supporting a mold comprising a plurality of mutually separable shell bodies for coating a pipeline section, wherein the assembly comprises motorized opening and closing of the shell bodies in a straight line. An assembly for supporting a bent pipeline section wherein the assembly comprises a base and a pair of arms extending from the base, wherein each arm comprises a respective clamping collar for clamping a bent pipe section between the arms. A vehicle for induction heating a bent pipeline section, wherein the vehicle comprises: a helical induction coil; and wheels arranged to guide movement of both ends of the induction coil through a tubular inside face of a bent pipeline section.

A method of coating a field joint, pipe sections for forming a coated field joint, and a coated field joint formed thereby. First and second angular cut backs are provided in the parent coating of each pipe section. The first angular cut back is at an angle of about 30°±5° relative to the longitudinal axis of the field joint, and the second angular cut back is positioned further from the field joint than the first angular cut back. The first and second angular cut backs result in the parent coating having a stepped profile, a step in the stepped profile between the first and second angular cut backs, the is substantially parallel to the longitudinal axis of the field joint and is free of indentations. The field joint coating is injection moulded to have an upstand that is less than or equal to about 5 mm.

A connector for lined pipelines includes a tube having opposed male interface elements extending inwardly from respective ends of the tube. One or more circumferential permeable chokes project radially from each male interface element. The chokes minimise flow of oxidising fluid from the bore into the micro-annulus between the liner and the pipe while maximising flow of fluid from the micro-annulus into the bore in the event of catastrophic pressure drop in the bore. To maintain gaps between the tube ends and the pipe liners for fluid flow, shoulder formations extend circumferentially around the tube. The connector may be used in a joint arrangement where each liner includes a body, an end of lesser thickness and greater bore than the body that terminates short of an end of the pipe, an inner step between the body and the end, and an outer step between the end and the pipe.

An integrity monitoring system for a lined pipeline is provided for monitoring the integrity of a polymer liner in a host pipe. Methods and apparatus are described by which a lined pipeline is provided with such an integrity monitoring system. Sensor cable is able to bridge a joint between sections at lined pipe, for example by routing the sensor cable across the joint via a channel in an electrofusion fitting or by connecting successive lengths of sensor cable via pass-throughs in an electrofusion fitting. Advantageously, the sensor cable is disposed within a continuous annulus between linings and host pipes, and the continuous annulus is maintained across pipe joints using electrofusion fittings.