The invention provides a steel cord for rubber reinforcement. The steel cord comprises a core strand and at least three outer strands twisted around the core strand, the core strand comprises at least one first core filament and multiple first outer filaments twisted around the first core filament, each outer strand comprises a number of second filaments, at least one of multiple first outer filaments is preformed prior to being twisted into the core strand, and at least one of second steel filaments is straight prior to being twisted to form each outer strand. The steel cord has improved performance on core filament migration.

Provided is a steel cord for rubber article reinforcement which has excellent corrosion resistance and productivity without deterioration of adhesion with rubber. A steel cord (1) for rubber article reinforcement, in which plural steel filaments (2) are twisted together, includes: a core having at least one core filament (2c); and a sheath having at least one sheath layer formed by twisting at least one sheath filament (2s) around the core. In this steel cord (1), brass plating is performed on the steel filaments (2) and zinc plating is further performed on the outer circumference of the brass plating of the core filament (2c), and the steel filaments (2) have a diameter d of 0.1 mm to 0.6 mm.

The subject of the invention is a cord (50) comprising a single layer (52) of helically wound metal filamentary elements (54). The metal filamentary elements define 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 Dv, Df and Rf being expressed in millimetres, the cord satisfies the following relationships:

9≤Rf/Df≤30, and

1.30≤Dv/Df≤2.10.

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 strainght 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.

A resin-covered cord including n number of individual cords, disposed so as to be mutually spaced apart from each other, a covering resin that covers the cords, and an adhesive resin that is disposed between the cords and the covering resin and that has a greater tensile elastic modulus than the covering resin. Equation (1) below is satisfied, in which A is a total value of a width direction dimension of a portion where the cords and the adhesive resin are disposed, and B is a maximum value of a thickness direction dimension.

B<(A/n) (n≥1)  Equation (1)

A method of manufacturing a tire including a reinforcing cord continuously wound a plurality of times in a tire circumferential direction or wound in the tire circumferential direction while continuously extending in a tire width direction.

A preceding carcass cord from one feeding unit is used to form a carcass layer while being fed to a forming drum, and a leading edge portion of a next carcass cord is paid out from another feeding unit in advance. When a predetermined length of the preceding carcass cord is fed, a splice mechanism is used to join the leading edge portion of the next carcass cord to the preceding carcass cord to make the leading edge portion of the next carcass cord continuous with the preceding carcass cord. Then, with the next carcass cord fed to the forming drum, formation of the carcass layer is continued to complete the carcass layer.

The present invention relates to a steel cord for rubber reinforcement wherein a steel wire for steel cord has a plating layer of a ternary or quaternary alloy.

The steel wire for the steel cord of the present invention comprises a plating layer of Cu-M-Zn (M is one or two elements of Co, Ni, Cr, Mo, Al, In, or Sn) and has a concentration gradient in which the M content ratio in a region from the surface to ¼ of the plating layer is 40% or more compared with the M content ratio in the entire region of the plating layer, and the steel cord for rubber reinforcement is obtained by a manufacturing method comprising: performing sequential plating on a surface of a steel wire in the order of Cu.fwdarw.M.fwdarw.Zn; performing a primary diffusion, for concentration gradient of M, by subjecting the sequentially plated steel wire to high-frequency induction heating using 1-500 MHz; and performing a secondary diffusion, following the primary diffusion, by medium-frequency induction heating using 10-500 KHz.

A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 95≤MC≤180, where MC=(J×MI+L×ME)/(J+L); MI=200×cos.sup.4(α)×[Q×(D1/2).sup.2×cos.sup.4(β)+P×(D2/2).sup.2×cos.sup.4(δ)+N×(D3/2).sup.2×cos.sup.4(γ)]/[Q×(D1/2).sup.2+P×(D2/2).sup.2+N×(D3/2).sup.2]; and ME=200×cos.sup.4(α′)×[Q′×(D1′/2).sup.2×cos.sup.4(ββ)+P′×(D2′/2).sup.2×cos.sup.4(δ′)+N′×(D3′/2).sup.2×cos.sup.4(γ′)]/[Q′×(D1′/2).sup.2+P′×(D2/2).sup.2+N′×(D3′/2).sup.2], where D1, D1′, D2, D2′, D3 and D3′ are in mm, α and α′ are the helix angle of each internal and external strand (TI), β and β′ are the helix angle of each internal thread (F1, F1′), δ and δ′ are the helix angle of each intermediate thread (F2, F2′) and γ and γ′ are the helix angle of each external thread (F3, F3′).

The various embodiments relate to pneumatic tires including a cap ply of braided strands of yarn. Various embodiments relate to strands of yarn that are fiberglass filaments or steel. The braided strands may include a tight braid or a loose braid. Various embodiments include braids having 1 to 5 stitches per cm.

Disclosed are a metal wire, a manufacturing method therefor, and a tire. The metal wire is made by twisting a filament; an outer peripheral surface of the filament is covered with a Cu-M-Zn alloy coating; the outer peripheral surface of the filament is also covered with a Cu—Zn alloy coating; the metal wire is made of at least one filament; an area covered by the Cu-M-Zn alloy coating is 10%-90% of an area of the outer peripheral surface of the filament, and the rest is the Cu—Zn alloy coating; M in the Cu-M-Zn alloy coating is selected from one or two of Co, Ni, Mn, or Mo; the mass fraction of Cu in the Cu-M-Zn alloy coating is 58%-72%, the mass fraction of M in the Cu-M-Zn alloy coating is 0.5%-5%, and the balance in the Cu-M-Zn alloy coating is Zn and inevitable impurities.