Nv Bekaert Sa

Aijun Zhang

Haijun Ma

Wei Zhou

Haidong Xi

Yaodong Li

The invention provides a steel cord with a construction of n×1, n is the number of the steel filaments of the steel cord, the steel cord has an elongation at 2.5N-50N of less than 1.2% and a twist pitch of greater than 16 mm, each of the steel filaments has a form of helical wave with a wave length L expressed in mm and a wave height H expressed in mm when being unravelled from said steel cord, L is greater than 16 mm, each of the steel filaments has a space volume Vs satisfying that, Vs=L×H×π/4, and Vs>20 mm. The invention steel cord is beneficial for the stress distribution.

Steel cord for rubber reinforcement

The invention provides a steel cord, the steel cord comprises two or more steel filaments, at least one of the steel filaments has a twist pitch of 6 mm to 40 mm, each of the steel filaments has a tip rise of less than 5 mm with a gauge length of 200 mm after being unravelled out of the steel cord. The invention steel cord has an improved straightness with reduced steel filament fracture risk.

A steel cord with a construction of m+n having a first group of core filaments having a number of m and a second group of sheath filaments having a number of n, the second group and the first group are twisted around each other with the same twist pitch and same twist direction, wherein the core filaments are not twisted with each other, the core filaments are parallel or have a twist pitch being more than 300 mm, and the sheath filaments have a twist pitch being less than or equal to 30 mm, the core filaments have an average tensile strength Tc in MPa when being un-ravelled from said steel cord, the sheath filaments have an average tensile strength Ts in MPa when being un-ravelled from said steel cord, Tc and Ts satisfy: 5<(Tc−Ts)<200. The steel cord has high breaking load and high production efficiency without cost increase.

A steel cord for rubber reinforcement that has a construction with an outer layer and an inner strand surrounded by and adjacent to the outer layer, the inner strand having at least one steel filament with a number of Nand an average diameter of dexpressed in mm, the outer layer having steel filaments with a number of Nand an average diameter of dexpressed in mm. The inner strand has a torque Tand the outer layer has a torque T, the relation between Tand Tis defined. By doing this, the tip rise problem of the rubber ply reinforced by steel cords is reduced.

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.

Growing community of inventors

Jiangyin, China

Aijun Zhang