A super-long thermal insulation steel jacket pipe and a machining process for making such a pipe are provided. The pipe is designed to exhibit good thermal insulation performance and corrosion resistance. An annular cavity of the pipe is in a vacuum state, and the pipe is internally provided with a support frame and filled with a phase change material. When the pipe is used for underground energy exploitation, temperature in a working steel pipe in the pipe can be effectively kept unaffected when external temperature decreases. The steel jacket pipe has long service life, and can greatly reduce costs of exploitation of petroleum and/or of an underground heat source, such as by reducing a heat loss in exploitation.

Method for manufacturing a tube of metal in which sensors are attached to tubes, which register and signal a damage of the tube. It is detrimental that protection of the sensors at these tubes against environmental influences is complex. In contrast, it is an object of the present disclosure to provide a method for manufacturing a tube, in which the signal line can be protectively mounted. To solve this object, a method for manufacturing a tube of metal is suggested with an outer tube and an inner tube, wherein a groove is drawn in an inner surface of the outer tube or in an outer surface of the inner tube and subsequently the inner tube and the outer tube are drawn together through a drawing die, wherein the inner dimension of the outer tube is reduced such that after the drawing the outer tube is force-fitted onto the inner tube.

The application relates to a method for producing a double-walled pipe (1) and a pipe (1) of this type, hating an outer pipe (3) which is press-fitted with an inner pipe (2) consisting of a corrosion-resistant alloy, wherein an adhesive (4) is inserted at least in regions between the outer pipe (3) and the inner pipe (2), wherein, after adhering the inner pipe (2) with the outer pipe (3), the inner pipe (2) and the adhesive layer (4) are removed at the pipe ends, and the inner side of the outer pipe (3) is plated via an integral connection with the inner pipe (2).

A conduit (100) for transporting a fluid comprises a first collar (102), a second collar (103), and a bellows (108). The bellows (108) comprises a corrugated inboard ply (110), a corrugated outboard ply (112), and an interstitial space (126). The conduit (100) also comprises a first weld (138), hermetically coupling the corrugated inboard ply (110), the corrugated outboard ply (112), and the first collar (102) and comprises a second weld (183), hermetically coupling the corrugated inboard ply (110), the corrugated outboard ply (112), and the second collar (103). The conduit (100) additionally comprises a weld-through ring (150), located between the corrugated inboard ply (110) and the corrugated outboard ply (112) and coupled to the first collar (102) by the first weld (138). The conduit (100) also comprises a sensor (116) that is communicatively coupled with the interstitial space (126) via the channel (118) of the first collar (102).

A conduit (100) for transporting a fluid comprises a first collar (102), a second collar (103), a bellows (108), and a sensor (116). The bellows (108) comprises a central axis (180), a first corrugated outboard ply (114), a corrugated inboard ply (110), interposed between the first corrugated outboard ply (114) and the central axis (180), an interstitial space (126), interposed between the corrugated inboard ply (110) and the first corrugated outboard ply (114), and a second corrugated outboard ply (112) within the interstitial space (126). The corrugated inboard ply (110), the first corrugated outboard ply (114), and a weld-through ring (150) are welded to the first collar (102) and the second collar (102). The second corrugated outboard ply (112) is not hermetically coupled to the first collar (102) or the second collar (103). The sensor (116) is communicatively coupled with the interstitial space (126).

A method and apparatus for producing a curved tubular segment includes obtaining a curved external tubular element and a curved internal tubular element. The curved internal tubular element is made of a material having a resistance to wear greater than that of the curved external tubular element and has a cross section such as to cover at least part of the internal surface of the curved external tubular element. The curved internal tubular element is inserted inside the curved external tubular element after heating the latter by a heating unit. To form the curved external tubular element on the exact geometry of the curved internal tubular element, a molding unit and a cooling unit are used to obtain a curved tubular segment without spaces between the curved external tubular element and the curved internal tubular element.

The invention relates to a method and a coating device for applying a cladding layer onto the inner side of a carrier layer during the production of a multilayer heavy-duty pipe, with a pressure-exerting unit having a force application unit. A stable application of the cladding layer is achieved by having the coating device comprise a rolling tool with the pressure-exerting unit and the force application unit, and by providing the pressure-exerting unit with at least one pressure roller having a diameter that is smaller than the inside diameter of the heavy-duty pipe to be produced, and with at least one support element acting diametrically counter thereto with a supporting force in the operating state.

Method for producing a high-pressure tube with inner tube and outer tube made of metal are drawn together through a first drawing die. The outer diameter of the inner tube is smaller than the inner diameter and drawing forms a very stable frictional connection between the inner tube and the outer tube. The manufactured tube has a large wall thickness and is very robust and pressure-resistant while having a very high quality outer shell surface and in particular a very high quality inner shell surface by virtue of the cold forming process. These two properties allow a sufficiently high protection against bursting when pressures in excess of 12,000 bar are applied to the tube. The produced tube has improved dynamic pressure resistance against high pressures by combining a large wall thickness of the tube to be manufactured with a high quality inner shell surface of the tube to be manufactured.

Nitrogen (N) absorption and diffusion treatments are performed for the inner and/or outer surfaces of austenite stainless steel pipe materials in N gas atmosphere at temperatures near 1,100 C. to obtain nitrided stainless steel pipe materials having 0.251.7% (mass) of solid solution nitrogen (N) including a gradient structure formed within the pipe wall in which the concentration of solid solution N continuously decreases gradually from the surface. The solid solution N present in the gradient structure promotes short range ordering (SRO) of substitutional alloying elements leading to homogenization of distribution of alloying elements in the austenite phase, generating an extremely high proof strength (yield strength) about 3 times as high as that of conventional austenite stainless steel pipe materials and enhancing characteristic of anti-hydrogen gas embrittlement (anti-HGE) so as to be suitable for use in a high pressure hydrogen tank utilized in hydrogen cell vehicle (FCV) and a liquid hydrogen tank.

A coated metal pipe for use as an automotive fluid transport tube and including any of a single or double walled tubing formed into a circular cross sectional profile. An intermediate primer layer is applied over the tubing. A polyamide incorporating a graphene powder is further applied over the intermediate layer.