A coated metal pipe for use as an automotive fluid transport tube is provided comprising: a single or double walled tubing formed into a circular cross-sectional profile; at least one intermediate layer primer layer applied over said tubing: and an outer layer comprising a polyamide incorporating an immiscible additive. The immiscible additive is selected from Ultra High Molecular Weight (UHMW) silicones, UHMW polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE) and mixtures thereof.

A method of making mechanically-lined pipe with primary expansion by plastically expanding a liner sleeve within an outer pipe, under lining pressure applied internally to the liner sleeve. On relieving the lining pressure, elastic radial contraction of the outer pipe makes a mechanical bond between the outer pipe and the liner sleeve. Then, secondary expansion of the outer pipe is performed under fixing pressure, which may be greater than the lining pressure, applied internally to the liner sleeve at an end portion of the pipe. This makes or strengthens a mechanical bond at the end portion. The resulting pipe joint has an end portion and a body portion inboard of the end portion. The body portion has a first, lesser bonding pressure between the outer pipe and the liner sleeve. The end portion has a second, greater bonding pressure between the outer pipe and liner sleeve.

A method of making mechanically-lined pipe with primary expansion by plastically expanding a liner sleeve within an outer pipe, under lining pressure applied internally to the liner sleeve. On relieving the lining pressure, elastic radial contraction of the outer pipe makes a mechanical bond between the outer pipe and the liner sleeve. Then, secondary expansion of the outer pipe is performed under fixing pressure, which may be greater than the lining pressure, applied internally to the liner sleeve at an end portion of the pipe. This makes or strengthens a mechanical bond at the end portion. The resulting pipe joint has an end portion and a body portion inboard of the end portion. The body portion has a first, lesser bonding pressure between the outer pipe and the liner sleeve. The end portion has a second, greater bonding pressure between the outer pipe and liner sleeve.

Vibration absorption tubing and a manufacturing method thereof. The manufacturing method includes: a solder placement step including: placing solder at solder placement portions in an inner cavity of an adaptor; a pipe fitting step including: fitting a corrugated pipe and the adaptor respectively to adaptor matching portions at corresponding sides of the adaptor, to communicate an adaptor inner cavity with an inner cavity of the corrugated pipe and inner cavities of external connection tubing; and fixing or limiting positions of the corrugated pipe, the adaptor, and the external connection tubing to obtain a tubing assembly; and a component brazing step including: performing furnace brazing on the tubing assembly of the external connection tubing to obtain a main vibration absorption tubing. The vibration absorption tubing has favorable brazing consistency, enhancing connection reliability of components.

Vibration absorption tubing and a manufacturing method thereof. The manufacturing method includes: a solder placement step including: placing solder at solder placement portions in an inner cavity of an adaptor; a pipe fitting step including: fitting a corrugated pipe and the adaptor respectively to adaptor matching portions at corresponding sides of the adaptor, to communicate an adaptor inner cavity with an inner cavity of the corrugated pipe and inner cavities of external connection tubing; and fixing or limiting positions of the corrugated pipe, the adaptor, and the external connection tubing to obtain a tubing assembly; and a component brazing step including: performing furnace brazing on the tubing assembly of the external connection tubing to obtain a main vibration absorption tubing. The vibration absorption tubing has favorable brazing consistency, enhancing connection reliability of components.

Copper alloys exhibiting enhanced oxidation resistance are provided by adding an amount of sulfur that is effective to enhance oxidative resistance. Such sulfur addition can be achieved by combining elemental forms of copper and sulfur and heating the mixture to form a molten alloy, or by forming a sulfur-rich pre-mix that is added to a base alloy composition. Forming a pre-mix provides improved homogeneity and distribution of the sulfur predominantly in the form of a metal sulfide.

Copper alloys exhibiting enhanced oxidation resistance are provided by adding an amount of sulfur that is effective to enhance oxidative resistance. Such sulfur addition can be achieved by combining elemental forms of copper and sulfur and heating the mixture to form a molten alloy, or by forming a sulfur-rich pre-mix that is added to a base alloy composition. Forming a pre-mix provides improved homogeneity and distribution of the sulfur predominantly in the form of a metal sulfide.

A method of manufacturing a steel strip for coiled tubing includes melting molten steel having a composition including, in terms of percent by mass, C: 0.10% or more and 0.16% or less, Si: 0.1% or more and 0.5% or less, Mn: 0.5% or more and 1.5% or less, P: 0.02% or less, S: 0.005% or less, Sol. Al: 0.01% or more and 0.07% or less, Cr: 0.4% or more and 0.8% or less, Cu: 0.1% or more and 0.5% or less, Ni: 0.1% or more and 0.3% or less, Mo: 0.1% or more and 0.2% or less, Nb: 0.01% or more and 0.04% or less, Ti: 0.005% or more and 0.03% or less, N: 0.005% or less, and the balance of Fe and inevitable impurities; casting the molten steel into a steel material; subjecting the steel material to hot rolling; and coiling a resultant steel strip, wherein a finish rolling temperature is 820° C. or more and 920° C. or less, a coiling temperature is 550° C. or more and 620° C. or less, and a time taken from the finish hot rolling to the coiling is 20 seconds or less.

Within examples, a method of manufacturing a double-walled titanium conduit is described. Example methods include stitch welding multiple concentric sheets to form a stitch layer, providing the stitch layer between an inner wall and an outer wall of the double-walled titanium conduit, circumferentially seam welding the inner wall and the outer wall to the stitch layer to create a welded assembly, die forming the welded assembly at temperature and pressure to form inner structures between the multiple concentric sheets according to stitch welding lines and to enable a diffusion bond process among the inner wall, the stitch layer, and the outer wall, and removing the double-walled titanium conduit from the die.

Within examples, a method of manufacturing a double-walled titanium conduit is described. Example methods include stitch welding multiple concentric sheets to form a stitch layer, providing the stitch layer between an inner wall and an outer wall of the double-walled titanium conduit, circumferentially seam welding the inner wall and the outer wall to the stitch layer to create a welded assembly, die forming the welded assembly at temperature and pressure to form inner structures between the multiple concentric sheets according to stitch welding lines and to enable a diffusion bond process among the inner wall, the stitch layer, and the outer wall, and removing the double-walled titanium conduit from the die.