D07B2201/2025

Metallic reinforcing cord for tyres for vehicle wheels

The invention relates to a metallic reinforcing cord for tyres for vehicle wheels, comprising at least two metallic wires twisted together with a predetermined twisting pitch, wherein the metallic reinforcing cord has a part load elongation greater than 3%, preferably greater than 3.5%.

Double-layer multi-strand cable having improved bending endurance

A multi-strand cord (50) comprises an internal layer (CI) of the cord made up of K=1 three-layer (C1, C2, C3) internal strand (TI), with the internal layer (C1) being made up of Q internal metallic threads (F1), the intermediate layer (C2) being made up of M intermediate metallic threads (F2) and the external layer (C3) being made up of N external metallic threads (F3), and an external layer (CE) of the cord made up of L>1 three-layer (C1, C2, C3) external strands (TE) wound around the internal layer (CI) of the cord, with the internal layer (C1) being made up of Q internal metallic threads (F1), the intermediate layer (C2) being made up of M intermediate metallic threads (F2) and the external layer (C3) being made up of N external metallic threads (F3). The cord (50) has an endurance criterion SL40 000 MPa.Math.mm with S L = max ( bending _ CI Cp ; bending _ CE C r Cp ) ;
and a size criterion Ec0.46 with Ec=Sc/Se.