Abstract: A compact steel cord is provided. The cord includes a core-filament I steel wire with a diameter of d0, and four middle-layer M steel wires with a diameter of d1 and eight outer-layer O steel wires with a diameter of d2 that are twisted around the core-filament I steel wire in the same lay direction and the same lay length. Gaps L are reserved between the outer-layer O steel wires, an average width of the gaps L is not smaller than 0.02 mm, and the total size of the gaps L is larger than d0 and smaller than d1. The steel cord of a stable structure can be obtained by controlling the proportion of the sizes of all layers of monofilaments, the rubber coating performance of a tire cord can also be improved, the corrosion resistance, fatigue resistance, impact resistance and adhesion retention of a tire are improved.

Abstract: A steel cord and a manufacturing process are disclosed. The steel cord includes a steel core wire located in the center and having a diameter of d; and M sheath-layer steel wires arranged around the steel core wire in the center, tangent to the steel core wire, and having a diameter of d1, at least two gaps L existing between the M sheath-layer steel wires, where M is 4; d, d1, and L satisfy the following relationship: 0.420<(d/d1)<0.800, d1 is between 0.20 mm and 0.44 mm, and L?0.0008 mm. The steel cord of the present invention may allow rubber to be fully penetrated into the gaps, thereby reducing air content in the steel cord, avoiding point contact friction between the layers of steel wires due to insufficient rubber penetration, and further solving the problem of failure of the bearing capacity of the steel cord due to abrasion.