A metal pipe having at least one smooth portion and at least one grooved portion is obtained by progressive deformation of its wall in at least two consecutive phases. Each phase is carried out using a tool assembly including a grooved female die that accommodates the portion of pipe being deformed, and a grooved male punch that moves axially in order to give the pipe a cross section with an undulating profile, defining longitudinal ribs distributed around the pipe. The majority of the ribs each have a width in the circumferential direction that is less than the distance in the circumferential direction from one rib to the next. The pipe is subjected to a further deformation step in order to force the flanks of each rib into contact with each other using a tool assembly that includes radially movable sectors or a bushing that supports a plurality of radial rollers.

A single piece stent construction having a plurality of commissure posts, each of which extends upwardly from a solid ring along a bend line and generally along a central longitudinal axis of the stent.

A support structure may include a metallic tube having two opposing ends. The first end may have a first length, a first wall thickness, and a first outer diameter. The second end may have a second length, a second wall thickness, and a second outer diameter. A transition area may be disposed between the first length and the second length. The first wall thickness may be greater than the second wall thickness thereby providing variable thickness.

In a method for the production of a heat exchanger, a turbulator insert is placed into a heat exchanging tube, with the turbulator insert having a solder applied thereon in at least one region. Weld spots using resistance welding are formed on an inner surface of the heat exchanging tube with the turbulator insert, and the inner surface of the heat exchanging tube is interlinked with the turbulator insert through brazing.

The invention is a structural metal tube with a built-in thermal break composed of only four components, two metal extruded portions and two composite strut portions. The thermal break between the metallic portions interrupts the otherwise high thermal conductivity that would exist if the metallic portions were joined. The low-thermal-conductivity composite strut portions disrupt the thermal conductivity between the metallic portions.

Apparatus (10) for forming a spirally wound conduit (14) from a flat strip (2) comprising: a forming device (6) comprising a bending section (7) configured to spiralling bend the strip (2) and a joining section (8) configured to join opposite longitudinal sides (2A,2B) of the strip (2) each other; a feeding device (11) of the strip (2) along a feeding direction (F) parallel to the longitudinal edges (9) of the strip (2); a cutting device (1) arranged upstream the forming device (6) comprising a cutting head (3) for cutting the strip (2) and moving means configured to move said cutting head (3) along a plurality of moving axes (X,Y,Z) orthogonal to each other; a control unit (18) configured to command said moving means according to diameter (D) of the conduit (14) to be realized and to the width (B) of the strip (2) so that said cutting head (3) realizes on the strip (2) a plurality of arrays (12) of holes (13) each one tilted with respect to one of the longitudinal edges (9) of the strip (2) by an angle () function of the width (B) of the strip (2) and of the diameter (D) of the spiral conduit (14) to be realized. The present invention relates also to a air conduit (14), a perforated strip (2) and a coil (19) of a perforated strip (2) comprising a plurality of said arrays (12) of holes (13) wherein said holes (13) comprise at least two different shapes.

A helically wound tubular structure formed from helically wound sheet metals is disclosed. The tubular structure has a first sheet metal helically wound about a longitudinal axis. A second sheet metal having voids disposed therein is helically wound about the longitudinal axis and coaxially about the first sheet metal. A third sheet metal is helically wound about the longitudinal axis and coaxially about the first sheet metal and the second sheet metal.

One aspect relates to a process for preparing a ring electrode including the steps of a) providing a monolithic metal precursor, wherein the monolithic metal precursor includes an outer tube forming a first cavity of the precursor, and wherein the outer tube has a wall including in one section an inner tube forming a second cavity of the precursor; b) preparing a composite precursor by inserting a first sacrificial core element into the first cavity of the precursor provided in a) and a second sacrificial core element into the second cavity of the precursor provided in a); c) forming the composite precursor obtained in b) to obtain a formed composite having a smaller outer diameter than the composite precursor obtained in b); d) separating a composite disk from the formed composite obtained in c); e) removing the first and the second sacrificial core element from the composite disk obtained in d).

A method for manufacturing a double-wall heat-exchanger tube including an external tube and an internal tube, these tubes being metallic, cylindrical and coaxial. This method includes providing a first tube having an inside diameter d.sub.1int and an outside diameter d.sub.1ext, this first tube being intended to form the external tube, a second tube having an inside diameter d.sub.2int and an outside diameter d.sub.2ext, this second tube being intended to form the internal tube, and a cylindrical coaxial tubular leaf made from Fe.sup.0 having an inside diameter d.sub.int and an outside diameter d.sub.ext, such that 0.15 mm(d1intdext)0.25 mm, 0.15 mm(dintd2ext)0.25 mm, and 10 m(dextdint)200 m.

Disclosed is a manufacturing apparatus for a tubular body of an electric vehicle rectangular battery can, configured to precisely manufacture the tubular body of the rectangular aluminum battery can using only aluminum extrusion, to use aluminum alloy 6063 having significantly increased strength after heat treatment compared to aluminum alloy 3003 so as to perform a cutting process without a cold working step, to adjust a bearing length for each portion of an extrusion mold depending on a thickness of an extrusion tubular body to be extruded from the extrusion mold so as to increase flatness of the extrusion tubular body, and to reduce a thickness tolerance. The manufacturing apparatus includes a flattening means installed at an outlet of the extrusion mold and configured to pressurize upper and lower surfaces of the extrusion tubular body, thereby maintaining flatness of the extrusion tubular body and preventing dimensional deformation thereof.