A layer of wires is preliminarily stranded by a layer of strand-through holes, and a first strand cylinder is used for the second pressing and stranding. The next layer of special-shaped single wires is stranded through a second pre-stranding assembly, and then the last layer of wires is stranded through a main stranding mold, thus stranding a plurality of layers at the same time with a compact structure. The outer circumference of the guide roller matches that of the special-shaped single wire, avoiding the reduced quality of stranded cable. The first rotating connector is bowl-shaped and is provided with a layer of strand-through holes together with a structure in which a first pull rod is in fit with the rotating connector and a structure in which a second pull rod is in fit with the rotating connector.

In a tire the strength of steel cord and the resilience of rubber are a successful combination. However, in some specific areas of a tire, more elongation is expected from the steel cord, while still a sufficient degree of stiffness is expected. A steel cord is presented that has these properties. The steel cord comprises two or more steel elements that are twisted together. The steel elements comprise one or more steel filaments. In total the steel cord comprises N filaments, each with a cross sectional area A. When the steel elements are individualised out of the steel cord they show a helix pitch length of L.sub.o, while a single pitch has a centre line length of S. The inventive steel cord shows a P value of at least 50 newton, wherein P=NE (A/S).sup.2. Further methods are presented to produce this steel cord.

An apparatus for producing an assembly of filamentary elements that are wound together in a helix includes a twisting device, a preforming device, and an assembling device. The twisting device is structured to twist at least first and second filamentary elements individually, such that each filamentary element is twisted separately from another filamentary element, to produce at least first and second twisted filamentary elements. The preforming device, which is arranged downstream of the twisting device, is structured to preform each of the twisted filamentary elements individually into separate preformed helixes, to produce at least first and second preformed helixes. The assembling device, which is arranged downstream of the preforming device, is structured to assemble the preformed helixes into an assembly.

Hybrid rope (20) comprising a core element (22) containing high modulus fibers surrounded by at least one outer layer (24) containing wirelike metallic members (26). The core element (22) is coated (23) with a thermoplastic polyurethane or a copolyester elastomer, preferably the copolyester elastomer containing soft blocks in the range of 10 to 70 wt %. The coated material (23) on the inner core element (22) is inhibited to be pressed out in-between the wirelike members (26) of the hybrid rope (20) and the hybrid rope (20) has decreased elongation and diameter reduction after being in use.

A device, which converts a reinforcing strip from being flat to being undulating, includes a transporter that guides fingers along a closed circuit, with the fingers being able to bear against a first face of the strip; a support plate that rotates about a plate axis and that supports rollers having axes parallel to the plate axis, with the rollers being able to bear against a second face of the strip; and a synchronizer that synchronizes a rotation of the support plate and a forward motion of the transporter. The closed circuit has an intersecting portion at which the synchronizer allows the fingers and the rollers to move rotationally in a common plane perpendicular to the plate axis, with the fingers and the rollers being interposed at the intersecting portion so as to cause the strip to have undulating waves that extend in the common plane.

A multi-strand cord (50) having a 1N structure comprises a single layer (52) of N strands (54) wound in a helix about a main axis (A), each strand (54) having one layer (56) of metal filaments (F1) and comprising M>1 metal filaments wound in a helix about an axis (B). The cord (50) has a total elongation At>8.10% and the energy-at-break indicator Er of the cord (50), defined by Er=.sub.0.sup.At(Ai)dAi where (Ai) is the tensile stress in MPa measured at the elongation Ai and dAi is the elongation such that Er is strictly greater than 52 MJ/m.sup.3.

The method makes it possible to manufacture an assembly (A) comprising a layer (C) of metal filamentary elements (14) wound in a helix. The method comprises a step (100) of supplying a temporary assembly (22) comprising a layer (13) of M>1 metal filamentary elements (14) and a temporary centre (16), and a step (110) of separating the temporary assembly (22) between a first split assembly (25), a second split assembly (27) and the temporary centre (16). The method comprises a step (140) of reassembling the first split assembly (25) with the second split assembly (27) so as to form the layer (C) of the assembly (A).