TWO-LAYER MULTI-STRAND CORDS HAVING VERY LOW, LOW AND MEDIUM MODULI

摘要

A two-layer multi-strand cord (60) comprises an internal layer (CI) of the cord made up of J>1 internal strands (TI) and an external layer (CE) of the cord made up of L>1 external strands (TE). The cord satisfies the relationship 95≤MC≤180, where MC=(J×MI+L×ME)/(J+L); MI=200×cos4(α)×[Q×(D1/2)2×cos4(β)+P×(D2/2)2×cos4(δ)+N×(D3/2)2×cos4(γ)]/[Q×(D1/2)2+P×(D2/2)2+N×(D3/2)2]; and ME=200×cos4(α′)×[Q′×(D1′/2)2×cos4(ββ)+P′×(D2′/2)2×cos4(δ′)+N′×(D3′/2)2×cos4(γ′)]/[Q′×(D1′/2)2+P′×(D2/2)2+N′×(D3′/2)2], where D1, D1′, D2, D2′, D3 and D3′ are in mm, α and α′ are the helix angle of each internal and external strand (TI), β and β′ are the helix angle of each internal thread (F1, F1′), δ and δ′ are the helix angle of each intermediate thread (F2, F2′) and γ and γ′ are the helix angle of each external thread (F3, F3′).