Spacers are provided for maintaining annular tube spacing, particularly at tube ends, in coaxial tubing systems, while also proving fluid passages ways permitting fluid flow between tubes of the coaxial tubing system. The spacers may be made of conductive material for enabling electrical coupling of the inner and outer tubes, and thus grounding of the inner tube. The spacers define a retention groove extending around their periphery for receiving a crimped portion of the outer tube, so as to mechanically fix the spacer in a longitudinal position relative to the coaxial tubing system. Accordingly, the spacer does not rely on “springbuck” characteristics of bent coaxial tubing systems for fixation, and thus is suitable for use in both bend and unbent portions of coaxial tubing systems.

A gas supply system, having a gas regulating station for supplying an engine with gaseous fuel and a double-walled gas line extending from the gas regulating station to the engine, which comprises an inner and an outer pipe, in a gas fuel operating mode the inner pipe is flowed through by the gaseous fuel towards an engine-side end of the double-walled gas line, an inert gas purging line, and a first shut-off valve assigned to the inert gas purging line. In a purging mode inert gas can be fed to the outer pipe at the gas regulating station-side, which inert gas flows through the outer pipe in the direction of the engine-side end of the double-walled gas line, where it passes into the inner pipe and flows via the inner pipe towards the gas regulating station-side end of the double-walled gas line.

A double pipe includes an outer pipe, an inner pipe, a fin member and a sealing part. The outer pipe has a plurality of outer crimping parts projecting to an inner diameter side and aligned in at least one of a lengthwise direction and a circumference direction. The inner pipe is arranged on an interior of the outer pipe with a flow path gap being defined between the outer pipe and the inner pipe. The inner pipe has a plurality of inner crimping parts aligned in the at least one of the lengthwise direction and the circumference direction and overlapping the outer crimping parts. The fin member is arranged on the interior of the inner pipe and held by the inner crimping parts. The sealing part seals between the outer pipe and the inner pipe.

A double pipe includes an outer pipe, an inner pipe, a fin member and a sealing part. The outer pipe has a plurality of outer crimping parts projecting to an inner diameter side and aligned in at least one of a lengthwise direction and a circumference direction. The inner pipe is arranged on an interior of the outer pipe with a flow path gap being defined between the outer pipe and the inner pipe. The inner pipe has a plurality of inner crimping parts aligned in the at least one of the lengthwise direction and the circumference direction and overlapping the outer crimping parts. The fin member is arranged on the interior of the inner pipe and held by the inner crimping parts. The sealing part seals between the outer pipe and the inner pipe.

A pipeline for conveying concrete determines a pressure in and/or a wall thickness of the pipeline, wherein a first length portion of the pipeline has a first wall thickness and a second length portion of the pipeline has a second wall thickness greater than the first wall thickness. The determination is made using a first strain gauge on an outer side of the first length portion and a second strain gauge on an outer side of the second length portion, wherein the strain gauges are each fixedly applied to the outer side of the length portions. By comparison of the measurements at the two strain gauges, it is possible to determine a wall thickness by determining a strain of the pipeline owing to a decrease in the wall thickness.

A pipeline for conveying concrete determines a pressure in and/or a wall thickness of the pipeline, wherein a first length portion of the pipeline has a first wall thickness and a second length portion of the pipeline has a second wall thickness greater than the first wall thickness. The determination is made using a first strain gauge on an outer side of the first length portion and a second strain gauge on an outer side of the second length portion, wherein the strain gauges are each fixedly applied to the outer side of the length portions. By comparison of the measurements at the two strain gauges, it is possible to determine a wall thickness by determining a strain of the pipeline owing to a decrease in the wall thickness.

There is presented a cable management apparatus for deployment within a pipe, where the pipe houses at least a portion of an umbilical cable. The cable management apparatus comprises a first engagement portion for engaging with an interior surface of the pipe, a second engagement portion for engaging with the umbilical cable, a first end and a second end. The cable management apparatus is configured such that, in use, the umbilical cable extends outwardly and away along the pipe, in substantially opposite directions from the first and second ends. The cable management apparatus is further configured to assist the moving of the umbilical cable along a lengthwise portion of the pipe using at least the first engagement portion and/or the second engagement portion.

There is presented a cable management apparatus for deployment within a pipe, where the pipe houses at least a portion of an umbilical cable. The cable management apparatus comprises a first engagement portion for engaging with an interior surface of the pipe, a second engagement portion for engaging with the umbilical cable, a first end and a second end. The cable management apparatus is configured such that, in use, the umbilical cable extends outwardly and away along the pipe, in substantially opposite directions from the first and second ends. The cable management apparatus is further configured to assist the moving of the umbilical cable along a lengthwise portion of the pipe using at least the first engagement portion and/or the second engagement portion.

A nozzle for controlling the flow of a water and/or gas component of a fluid produced from a hydrocarbon-bearing reservoir, the fluid comprising oil and water and/or gas, the nozzle comprising a fluid passage extending between an inlet and an outlet, wherein the fluid passage comprises an uneven surface for imparting turbulence to the water and/or gas component of the fluid.

A nozzle for controlling the flow of a water and/or gas component of a fluid produced from a hydrocarbon-bearing reservoir, the fluid comprising oil and water and/or gas, the nozzle comprising a fluid passage extending between an inlet and an outlet, wherein the fluid passage comprises an uneven surface for imparting turbulence to the water and/or gas component of the fluid.