A synthetic rope (20) comprises a core (22) and at least a first layer surrounding the core (22). The first layer has first layer strands (26). The core has a fluted outer surface with spaced apart helical concave grooves. Each of these grooves contacts one of the first layer strands (26). The grooves have a radius of curvature (24) that is greater than the radius of curvature (14) of a circle having a same diameter as the contacting first layer strand before twisting.

A synthetic rope (20) comprises a core (22) and at least a first layer surrounding the core (22). The first layer has first layer strands (26). The core has a fluted outer surface with spaced apart helical concave grooves. Each of these grooves contacts one of the first layer strands (26). The grooves have a radius of curvature (24) that is greater than the radius of curvature (14) of a circle having a same diameter as the contacting first layer strand before twisting.

According to embodiments of the present invention, a stranded conductor is formed in which the occurrence of defects, such as strand unevenness of filaments and outward protrusion of filaments, is inhibited. According to embodiments of the present invention, a stranded conductor (1a) includes soft filaments (2a) stranded together. The soft filaments (2a) include a soft filament made of an aluminum material, disposed along a center (101), and include six soft filaments, twelve soft filaments, and eighteen soft filaments made of an aluminum material, disposed around and concentrically with the center. The filaments are softened filaments that are softened. A lay length (Pa) is from 6.2 times to 15.7 times a conductor diameter of the stranded conductor.

According to embodiments of the present invention, a stranded conductor is formed in which the occurrence of defects, such as strand unevenness of filaments and outward protrusion of filaments, is inhibited. According to embodiments of the present invention, a stranded conductor (1a) includes soft filaments (2a) stranded together. The soft filaments (2a) include a soft filament made of an aluminum material, disposed along a center (101), and include six soft filaments, twelve soft filaments, and eighteen soft filaments made of an aluminum material, disposed around and concentrically with the center. The filaments are softened filaments that are softened. A lay length (Pa) is from 6.2 times to 15.7 times a conductor diameter of the stranded conductor.

A production method for a headline sonar cable characterized by steps of: a. providing a first strength member (14); b. coupling to strength member (14) a conductor (122); c. forming a layer of polymeric material about the combination of strength member (14) and conductor (122) while ensuring that the conductor remains slack; d. forming a flow shield around the layer of polymeric material, thus forming an elongatable internally located conductive structure; and e. braiding a strength-member jacket layer (52) of polymeric material around the elongatable internally located conductive structure while ensuring that the conductor is slack when surrounded by the jacket layer (52). For another embodiment, an optical fibre is wrapped around the exterior of the layer of polymeric material within which is enclosed a braided conductor formed about the first strength member (14). Other embodiments employ further thermo-plastic layers and further sheaths and further conductors.

A production method for a headline sonar cable characterized by steps of: a. providing a first strength member (14); b. coupling to strength member (14) a conductor (122); c. forming a layer of polymeric material about the combination of strength member (14) and conductor (122) while ensuring that the conductor remains slack; d. forming a flow shield around the layer of polymeric material, thus forming an elongatable internally located conductive structure; and e. braiding a strength-member jacket layer (52) of polymeric material around the elongatable internally located conductive structure while ensuring that the conductor is slack when surrounded by the jacket layer (52). For another embodiment, an optical fibre is wrapped around the exterior of the layer of polymeric material within which is enclosed a braided conductor formed about the first strength member (14). Other embodiments employ further thermo-plastic layers and further sheaths and further conductors.

A two-layer multi-strand cord (60) has a modulus EC such that 50 GPa≤EC≤160 GPa. The cord comprises: (a) an internal layer (CI) of the cord made up of J>1 internal strands (TI) wound in a helix having a modulus EI, each internal strand (TI) comprising: an internal layer (C1) made up of Q≥1 internal threads (F1), and an external layer (C2) made up of N>1 external threads (F2) wound around the internal layer (C1), and (b) an external layer (CE) of the cord made up of L>1 external strands (TE) wound around the internal layer (CI) of the cord, each external strand (TE) comprising: an internal layer (C1′) made up of Q′≥1 internal threads (F1′), and an external layer (C2′) made up of N′>1 external threads (F2′) wound around the internal layer (C1′).

A two-layer multi-strand cord (60) has a modulus EC such that 50 GPa≤EC≤160 GPa. The cord comprises: (a) an internal layer (CI) of the cord made up of J>1 internal strands (TI) wound in a helix having a modulus EI, each internal strand (TI) comprising: an internal layer (C1) made up of Q≥1 internal threads (F1), and an external layer (C2) made up of N>1 external threads (F2) wound around the internal layer (C1), and (b) an external layer (CE) of the cord made up of L>1 external strands (TE) wound around the internal layer (CI) of the cord, each external strand (TE) comprising: an internal layer (C1′) made up of Q′≥1 internal threads (F1′), and an external layer (C2′) made up of N′>1 external threads (F2′) wound around the internal layer (C1′).

Provided is a steel cord for rubber article reinforcement, which has both the tensile strength in the cord axial direction and the strength in the shear direction at higher levels. A steel cord (10) for rubber article reinforcement includes: a single core strand (11) having a layer-twisted structure; and plural sheath strands (12) each having a layer-twisted structure, and the sheath strands (12) are twisted around the core strand (11). In the sheath strands (12), a ratio between the diameter of a core filament (12a) and the diameter of a sheath filament (12b) is 0.75 to 0.85, and a ratio between the strength of the core filament (12a) and the strength of the sheath filament (12b) is 0.55 to 0.7.

Disclosed is a blended rope having an outer sheath (8) enclosing at least a strength member (7), the strength member (7) having high-strength synthetic fibers, the strength member (7) being a blended strength member (7) formed with a combination of ARAMID fibers and HMPE fibers, the blended strength member comprising a non-homogeneous distribution of the ARAMID and HMPE fibers, wherein the weight ratio of ARAMID to HMPE in the strength member (7) is preferably a minimum of 80:20.