The invention relates to a method for producing a component from a medium-manganese flat steel product with 4 to 12 wt % Mn, preferably more than 5 to less than 10 wt % Mn, and with TRIP/TWIP effect. In order to improve the degrees of deformation of the shaped component while at the same time reducing the forming forces, the invention proposes shaping the flat steel product into a component in a first shaping step at a temperature of the flat steel product of 60° C. to below Ac3, preferably from 60° C. to 450° C. The invention also relates to a component produced according to said method and to a use for said components.

A process for winding a convolutely wound tubular structure having a machine direction, a cross-machine direction coplanar thereto, and a Z-direction orthogonal to both the machine- and cross-machine directions is disclosed.

A double-wall spiral welded pipe includes a first steel belt layer and a second steel belt layer which have equal widths, are arranged in parallel and align with each other; at least two supporting steel bars perpendicular to the first steel belt layer and the second steel belt layer are arranged between the first steel belt layer and the second steel belt layer; the supporting steel bars are arranged on end parts of two sides of the first steel belt layer and the second steel belt layer and extend together with the first steel belt layer and the second steel belt layer; and the first steel belt layer, the second steel belt layer and the supporting steel bars on the end parts of the two sides are mutually welded to form a double-layer composite steel belt with a rectangular section in an extending direction.

A multilayer structure for transporting or storing gas or for exploiting oil or gas deposits under the sea, including, from the inside to the outside, at least one sealing layer and at least one composite reinforcing layer, the innermost composite reinforcing layer being welded to the outermost adjacent sealing layer, the sealing layers of a composition including at least one semi-crystalline thermoplastic polymer, the Tm of which is less than 280° C., wherein at least one of the composite reinforcing layers of a fibrous material in the form of continuous fibers impregnated with a composition including at least one thermoplastic polymer, the thermoplastic polymer having a Tg greater than the maximum temperature of use of the structure (Tu), with Tg≥Tu+20° C., Tu being greater than 50° C., and a multilayer structure selected from a reservoir, a pipe or a tube for transporting or storing hydrogen being excluded.

A pipe includes an elongate strip wound into a tubular pipe form with the upper surface and the ribs at an exterior of the tubular pipe form, and with a first portion of a first side overlapping a first portion of a second side along a helical joint. A plastic seam weld is applied between the overlapping first portions for bonding the overlapping first portions together. A plastic overweld extends over the overlapping first portions and over both a second portion of the first side and a second portion of the second side. The second portion of the first side is adjacent to the first portion of the first side and does not overlap with any part of the second side, and the second portion of the second side is adjacent to the first portion of the second side and does not overlap any part of the first side.

This steel sheet includes a first coated portion in which an intermetallic compound layer and an aluminum coating layer are provided on a surface of a base steel sheet in order from the base steel sheet side, a first exposed portion in which the base steel sheet is exposed, and a second coated portion in which the intermetallic compound layer and the aluminum coating layer are provided on the surface of the base steel sheet in order from the base steel sheet side, in which in a first direction which is perpendicular to a thickness direction of the steel sheet and is directed from the first coated portion to one end edge of the steel sheet, the first coated portion, the first exposed portion, the second coated portion, and the end edge of the steel sheet are disposed in this order on one surface of the base steel sheet, at least the first coated portion, the first exposed portion, and the end edge of the steel sheet are disposed in this order on the other surface of the base steel sheet in the first direction, and when viewing a cross section parallel to each of the first direction and the thickness direction of the steel sheet, the second coated portion is provided in a lower region which is located on the surface of the base steel sheet and on an inner side of the base steel sheet in the thickness direction of the steel sheet from a virtual line extending in the first direction from a boundary between the first exposed portion and the second coated portion.

A method for manufacturing an electric resistance welded steel pipe having an identifiable seam portion. The method includes electric resistance welding a steel pipe, cutting an inner surface bead and an outer surface bead of the steel pipe in such a manner so as to cut: (i) a whole the outer surface bead and a part of the inner surface bead to leave an uncut portion in the inner surface bead, or (ii) a whole of the inner surface bead and a part of the outer surface bead to leave an uncut portion in the outer surface bead, coating the steel pipe with zinc phosphate, and cold drawing the steel pipe using a plug and a die to make the seam portion of the steel pipe identifiable.

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.

The present invention discloses a metal strip winding continuous reinforced thermoplastic composite pipe. The present invention adopts a method designed for grouping the winding metal strips to rationally distribute the winding mode of the metal strips, and at the same time, increases the hoop strength and axial strength of the pipe by using the feature of high strength of the metal strips, thereby improving the compressive capacity of the pipe; there is no bonding between the metal strip reinforcement layers, which improves the flexibility of the composite pipe and reduces the relative slippage between the metal strip layers; the production process is simple, and requirements for the equipment investment are small, thereby greatly reducing the manufacturing cost and ensuring the flexibility and seismic resistance of the pipeline.

An electric-resistance-welded stainless clad steel pipe or tube that is excellent in both the fracture property of the weld and the corrosion resistance of the pipe or tube inner surface as electric resistance welded without additional welding treatment such as weld overlaying after electric resistance welding is provided. An electric-resistance-welded stainless clad steel pipe or tube comprises: an outer layer of carbon steel or low-alloy steel; and an inner layer of austenitic stainless steel having a predetermined chemical composition, wherein a flatness value h/D in a 90 flattening test in accordance with JIS G 3445 is less than 0.3, and a pipe or tube inner surface has no crack in a sulfuric acid-copper sulfate corrosion test in accordance with ASTM A262-10, Practice E, where h is a flattening crack height (mm), and D is a pipe or tube outer diameter (mm).