Abstract:
A steel cord used for reinforcing rubber product with an oval cross-section has a structure of m+n, while m is the number of core wires (26) and n is the number of the outer layer wires (22). The core wire (26) is untwisted while m is 1 or the core wires (26) are untwisted and aligned in parallel while m is between 2 and 4, and the outer layer wires (22) are twisted around said core wires (26). The core wires (26) are oval wires and the outer layer wires (22) are round wires. The wires (22, 26) in the steel cord have a carbon content not less than 0.60%.
Abstract:
Multistrand metal cord (C-1) having two layers (Ci, Ce) of J+K construction, which can especially be used for reinforcing tires for industrial vehicles, consisting of a core comprising J strands forming an inner layer (Ci), J varying from 1 to 4, around which core are wound, in a helix, with a helix pitch PK of between 20 and 70 mm, K outer strands forming an outer layer (Ce) around said inner layer (Ci), each outer strand: comprising a cord (10) having two layers (C1, C2) of L+M construction, rubberized in situ, comprising an inner layer (C1) comprised of L wires (11) of diameter d1, L varying from 1 to 4, and an outer layer (C2) of M wires (12), M being equal to or greater than 5, of diameter d2, which are wound together in a helix with a pitch p2 around the inner layer (C1); and having the following characteristics (d1, d2 and p2 being expressed in mm): 0.10
Abstract:
Multistrand metal cord of K×(L+M) construction, which can especially be used for reinforcing tire belts for industrial vehicles, consisting of K elementary strands assembled in a helix, with a helix pitch PK, each elementary strand: consisting of a cord (10) having two layers (Ci, Ce) of L+M construction, rubberized in situ, comprising an inner layer (Ci) consisting of L wires (11) of diameter d1, L varying from 1 to 4, and an outer layer (Ce) of M wires (12), M being equal to or greater than 5, of diameter d2, which are assembled in a helix with a pitch p2 around the inner layer (Ci); and having the following characteristics (d1, d2 and p2 being expressed in mm): 0.10
Abstract:
A steel cord (30) with a high elongation at break of at least 5% comprises n strands (20), each of said strands (20) has m filaments (10) twisted together, n ranges from 2 to 7. m ranges from 2 to 9. The strands and the filaments are twisted in a same direction. The lay length of the cord is Lc and the lay length of said strand is Ls. The ratio of Ls to Lc (Ls/Lc) ranges from 0.25 to 1. Lc ranges from 16 mm to 26 mm. The strands are helically preformed. The E-modulus of the cord is more than 150000 N/mm2. The helical preforming of the strands allows to obtain a high elongation at break and a high E-modulus despite its long lay length Lc.
Abstract:
A pneumatic tire for a passenger car includes a belt layer and a belt cover layer formed by winding a steel cord member in the tire circumference direction on the outer peripheral side of the belt layer. The steel cord member has a structure in which element wires made of steel and having a diameter smaller than 0.18 mm are twisted together to form each strand and the strands are twisted together in the same direction as the direction of twisting of the element wires. The twist pitch on each of the strands is smaller than the twist pitch on the steel cord member, the twist pitch on the strand is 1.0 mm to 2.1 mm, and the twist pitch on the steel cord member is 2.0 mm to 5.25 mm.
Abstract:
Metal cord (C-1) having two layers (Ci, Ce) of 3+N construction, rubberized in situ, comprising an inner layer (Ci) formed from three core wires (10) of diameter d1 wound together in a helix with a pitch p1 and an outer layer (Ce) of N wires (11) N varying from 6 to 12, of diameter d2, which are wound together in a helix with a pitch p2 around the inner layer (Ci), wherein said cord has the following characteristics (d1, d2, p1 and p2 are expressed in mm): 0.20
Abstract:
There is provided a steel cord including a plurality of untwisted core filaments of steel aligned in parallel, and a layer of sheath filaments of steel twisted around the core filaments so as to be unevenly distributed around the core filaments, wherein interstices between the filaments are maintained during vulcanization thereby achieving improved rubber penetration (sufficiently adhering rubber to the core filaments). Since the cross sectional length of the steel cord 10 is greater than the minimum cross sectional length, interstices A are maintained between sheath filaments 14 under the tension and pressure p of the surrounding rubber 16 applied to the steel cord 10 during vulcanization. Rubber 16 penetrates into the steel cord 10 through the interstices A, and sufficiently adhere to core filaments 12 to achieve high rubber penetration.
Abstract:
An annular metal cord includes an annular core portion and an outer layer portion. The annular core portion is formed by connecting together both ends of a first strand material which is made up of six twisted first metal filaments. The outer layer portion is formed by winding spirally a second strand material which is made up of six twisted second metal filaments around the annular core portion. The second strand material is wound at a predetermined winding angle relative to a center axis of the annular core portion, and a winding initiating end portion and a winding terminating end portion are connected together. As a result, the breaking strength of the annular metal cord can be made large, and the production thereof can be facilitated.
Abstract:
There is provided a steel cord including a plurality of untwisted core filaments of steel aligned in parallel, and a layer of sheath filaments of steel twisted around the core filaments so as to be unevenly distributed around the core filaments, wherein interstices between the filaments are maintained during vulcanization thereby achieving improved rubber penetration (sufficiently adhering rubber to the core filaments). Since the cross sectional length of the steel cord 10 is greater than the minimum cross sectional length, interstices A are maintained between sheath filaments 14 under the tension and pressure p of the surrounding rubber 16 applied to the steel cord 10 during vulcanization. Rubber 16 penetrates into the steel cord 10 through the interstices A, and sufficiently adhere to core filaments 12 to achieve high rubber penetration.
Abstract:
A steel cord which has no production problem noted in the related art and which can be produced efficiently with stable quality, particularly a steel cord useful for the purpose of reinforcing a tire crown portion, as well as a composite of rubber and steel cord and a tire, which include the steel cord, are provided.A steel cord has a multi-twist structure in which N (N=2 to 8) strands 2 are twisted, each strand 2 being formed by twisting a plurality of element wires 1 and having a substantially elliptical cross-section, wherein d1/d2>1.08 is satisfied, where the major diameter of the strand 2 is represented by d1 and the minor diameter is represented by d2, and εc defined by the following equation: εc=√{square root over ( )}(−b/2+√{square root over ( )}(b2/4−c))−1 (in the equation, b represents −1+π2(−4R2+d2)/P2, c represents π2d2k(4π2R2+P2)/P4, R represents (D−d)/2, k represents tan2(π/2−π/N), and d represents (d1+d2)/2) satisfies εc>0.005, where the diameter of a circle circumscribing the cord is represented by D (mm) and the twist pitch of the cord is represented by P (mm).