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).
Abstract:
Provided are a steel cord for reinforcing rubber whose fatigue resistance is increased more than ever to enable achieving high durability that was not conventionally realized, and a pneumatic radial tire including the steel cord as a reinforcement member.In a steel cord for reinforcing rubber having a double-twist structure that includes a plurality of strands twisted together in the same direction with the same pitch and including a central structure and at least one outer layer, the central structure is composed of at least two strands being twisted around each other and each being composed of at least seven filaments being twisted together. In a steel cord for reinforcing rubber including at least three core strands being twisted together and at least six sheath strands being twisted together around the core strands, the core strands and the sheath strands are twisted in the same direction.
Abstract:
A steel cord adapted for the reinforcement of elastomers includes: a core steel filament with a diameter dc and coated with a polymer, six intermediate steel filaments with a diameter di smaller than or equal to dc, the intermediate steel filaments being twisted around the core steel filament, ten to eleven outer steel filaments with a diameter do, smaller than or equal to di wherein these outer steel filaments are twisted around the intermediate steel filaments, and the outer steel filaments are preformed in order to allow rubber penetration inside the cord. The core steel filament, the intermediate steel filaments, and the outer steel filaments all have a tensile strength of at least 2600 MPa. The cord has an outer diameter D according to the following formula: D≦dc+2×di+2×do+0.1 mm, wherein all diameters are expressed in millimeters (mm).
Abstract translation:适用于增强弹性体的钢丝绳包括:具有直径d c c的芯钢丝,并涂覆有聚合物,六个中等长度的细长丝,直径小于或等于 中间钢丝缠绕在芯钢丝上,十到十一个直径小于或等于的钢丝, 其中这些外部钢丝围绕中间钢丝绞合,并且外部钢丝被预成型以允许橡胶在帘线内渗透。 芯钢丝,中间钢丝和外钢丝均具有至少2600MPa的拉伸强度。 帘线具有根据以下公式的外径D:D <= D i> + 2×2×2×2×↓+ 0.1mm,其中 所有直径以毫米(mm)表示。
Abstract:
A pneumatic tire includes metal cords each made of metal filaments twisted together, the metal cords having an initial elongation in a range of from 0.05 to 0.20% and a standard deviation of the initial elongation in a range of not more than 0.02. A method of manufacturing the metal cord comprises shaping metal filaments in a two-dimensional zigzag waveform, and twisting the shaped metal filaments together, wherein the number of the filaments is in a range of from 8 to 12, the metal filaments have the same diameter (d) of from 0.15 to 0.30 mm, the shaped metal filaments have the same zigzag waveforms, the zigzag waveform of each said shaped metal filament has constant wave lengths (P) and constant wave heights (h) wherein the ratio (P/d) is in the range of 100/3 to 700/3, and the ratio (h/d) is in the range of 5/3 to 80/3.
Abstract:
A steel cord (10) comprises a core with one or more core steel filaments (12) and further comprises a first layer of intermediate steel filaments (14) twisted around the core, and a second layer of second steel filaments (18) twisted around the first layer. At least one of the intermediate steel filaments is individually coated by means of a polymer (16) with a minimum thickness of 0.010 mm. The polymer (16) reduces the fretting between the coated intermediate steel filaments (14) and the other steel filaments and makes the steel cord suitable for reinforcement of carcass plies of a tire.
Abstract:
A hybrid cord which is characterized by (A) a core steel filament; (B) a first layer of one or more nonmetallic filaments which are wrapped about the steel filament in the core; and (C) a second layer of from 4 to 12 steel filaments which are wrapped about the first layer.
Abstract:
An extruded polymeric rod is elongated in the solid state by being drawn through a forming device to produce a solid polymeric core having an orientated structure which comprises elongated crystals orientated in the axial direction of the core. The core may also comprise crystals orientated in respective radial directions. The single rod may be replaced by a bundle of rods.
Abstract:
The invention is directed to several embodiments of metallic cord for the reinforcement of tires wherein one or more coaxial layers of metallic filaments are arranged around the metallic core filaments and twisted in the same direction at the same pitch. In one embodiment, the ratio of the diameter of the core filaments to the layer filaments is at least 1.28. In another embodiment, two of the core filaments have a first diameter and the third core filament has a second diameter smaller than the first diameter daimeter. In still another embodiment, two of the core filaments have a first diameter and a third of the core filaments has a second diameter smaller than the first diameter while the coaxial layer filaments have a third diameter equal to the second diameter. In another embodiment, the core has three core filaments twisted about each other and a coaxial layer of eight layer filaments arranged around the core filaments. In yet another embodiment, the core filaments have a first diameter and the layer filaments have a second diameter which is larger than the first diameter.
Abstract:
A wire rope is formed by twisting two different metal wires which vary from each other by at least 50% in their loss factors. The two different metal wires are combined in two embodiments: first, wires of steel material and wires of titanium containing material, or secondly, wires of a steel material and wires of chromium stainless steel material. In a preferred embodiment, a wire rope is formed by twisting a plurality of strands around a center core and two different metal wires as described above are employed to form the strands.