A manipulation rope having an excellent torque transmittability is provided. A manipulation rope is a rope that is advantageously used as a manipulation rope for a medical instrument, and includes a side wire or a side strand which is an outermost layer, the side wire or the side strand having a forming rate that is greater than 100% and not greater than 110%. The side wire or the side strand having been formed has a spiral shape in which a flatness that is an aspect ratio obtained by a major axis being divided by a minor axis is preferably not less than 1.01 and preferably not greater than 1.10. Further, an elongation of the rope at a time when a tensile load that is 1.0% of a breaking load is applied, is preferably not less than 0.04% and preferably not greater than 0.10%.

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.

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.

A steel cord for reinforcing a breaker or belt ply in a rubber tire having a core group and a sheath group. The core group consists of two to four core steel filaments with a first diameter dc and the sheath group consists of one to six sheath steel filaments with a second diameter ds. The ratio dc/ds of the first diameter dc to the second diameter ds ranges from 1.10 to 1.70. The two core steel filaments are untwisted or have a twisting step greater than 300 mm. The sheath group is twisted around the core group with a cord twisting step in a cord twisting direction. The ratio of the difference in residual torsions of the core group and the sheath group to the difference in saturation level between the core group and the sheath group ranges from 0.10 to 0.65, preferably from 0.10 to 0.60.

[Object] A hollow stranded wire line, for manipulation, having an excellent torque transmittability is provided. [Solution] A hollow stranded wire line 2 for manipulation is a hollow stranded wire line 2 that is advantageously used as a stranded wire line for manipulation in a medical instrument, and a side wire 4 or a side strand which is an outermost layer has a forming rate that is greater than 100% and not greater than 110%. The side wire 4 or the side strand having been formed has a spiral shape in which a flatness that is an aspect ratio obtained by a major axis being divided by a minor axis is preferably not less than 1.01 and preferably not greater than 1.10.

A facility for manufacturing at least first and second assemblies of M1 filamentary elements and M2 filamentary elements, in which each of the first and second assemblies includes a plurality of filamentary elements wound together in a helix, includes an assembling apparatus and a splitting apparatus. The assembling apparatus of the facility assembles M filamentary elements together into a layer of M filamentary elements around a temporary core, to form a temporary assembly. The splitting apparatus of the facility splits the temporary assembly into at least the first and second assemblies of M1 filamentary elements and M2 filamentary elements.

A method is provided for manufacturing at least first and second assemblies of M1 filamentary elements and M2 filamentary elements. At least one of the first and second assemblies includes a plurality of filamentary elements wound together in a helix. The method includes a step of assembling M filamentary elements together into a layer of the M filamentary elements around a temporary core, to form a temporary assembly. The method also includes a step of splitting the temporary assembly into at least the first and second assemblies of M1 filamentary elements and M2 filamentary elements.

The method enables the production of a final assembly (A) comprising two layers and comprises a step (100) of providing a temporary assembly (AT) comprising a temporary core (NT), a step (124) of separating the temporary assembly (AT) into a first divided assembly (AFI), a second divided assembly (AF2), a third divided assembly (AF3) and the temporary core (NT). The method comprises a step (135) of reassembling the first divided assembly (AFI), the second divided assembly (AF2) and the third divided assembly (AF3) to form the final assembly (A).

A cord (50) comprises a single layer (52) made up of N helically wound metal filamentary elements (54) having an outer diameter D, the metal filamentary elements (54) defining an internal enclosure (58) of the cord of diameter Dv. Each metal filamentary element (54) has a diameter Df and a helix radius of curvature Rf. With this cord (50), D, Dv, Df and Rf being expressed in millimeters: 0.10?Jr?0.25, 9?Rf/Df?30, and 1.60?Dv/Df?3.20, where Jr=N/(?*(D?Df))?(Dh?Sin(?/N)?(Df/Cos(???/180))) and ? is the helix angle, expressed in degrees, of each metal filamentary element (54).

A method for manufacturing a straight steel monofilament for the reinforcement of belt ply of a pneumatic tyre, where the arc-height of the straight steel monofilament is less than 30 mm. The steel monofilament is plastically deformed by a twisting along the axis of the steel monofilament on a double-twist apparatus. The plastic twist deformation eliminates the surface stress difference on the steel monofilament and provides a straight steel monofilament for belt ply reinforcement. This provides a simple solution with existing apparatus to manufacture straight steel monofilament suitable for tire reinforcement with high speed for mass production.