A steel cord containing a core layer and an sheath layer, the core layer containing a plurality of core wires with a number of n and the sheath layer comprises a plurality of sheath wires with a number of m, and the steel cord has a flat cross-section with a major axis and a minor axis, the flat cross-section has a flat ratio being the ratio of the length of the major axis and the length of the minor axis, the flat ratio is more than 1.2, the steel cord has a breaking load being BL.sub.cord, the core wires and the sheath wires have a sum breaking load being Sum BL.sub.wires when the core wires and the sheath wires are un-twisted from the steel cord, BL.sub.cord and Sum BL.sub.wires satisfies the following formula: BL.sub.cord/Sum BL.sub.wires>96%. The steel cord has higher breaking load.

The invention relates to a multi-strand cord (50) comprising 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 SL≤40 000 MPa.Math.mm with

[00001]$SL=\max \left(\frac{\Delta {\sigma }_{\mathrm{bending}\_\mathrm{CI}}}{\mathrm{Cp}};\frac{\Delta {\sigma }_{\mathrm{bending}\_\mathrm{CE}}}{C_r\times \mathrm{Cp}}\right);$  and a size criterion Ec≥0.46 with Ec=Sc/Se.

A cord comprises a braided sheath of strands having an outer surface, an inner surface, and a central hollow portion defined by the inner surface and having a volume and a core within the central hollow portion of the tubular braided sheath, such that when the cord is in a relaxed state the tubular braided sheath has a cylindrical shape and a relaxed volume of the central hollow portion wherein the core does not fill the relaxed volume of the central hollow portion of the tubular braided sheath; when the cord is in a longitudinal tensioned state, the tubular braided sheath elongates under the longitudinal tension such that a tensioned volume of at least a part of the central hollow portion of the tubular braided sheath is less than the relaxed volume; and the inner surface of the tubular braided sheath of tensioned volume contacts and cinches a surface of the core.

Disclosed is a method for producing a high strength synthetic strength member containing rope and a resultant rope, comprising multiple layers of twisted and braided yarns, wherein individual sheaths enclosing individual strands are of a material such as HMPE, PTFE or UHMWPE with a lower decomposition temperature than the material of said strands being aramid, the method comprising subjecting parts of the rope to heat and tension thereby pre-stretching and creating a non-uniform or non-round shape of said strands, further choosing a combination of braid and twist angles as well as braid compressive forces to accommodate specific strength and elongation relation between the individual rope layers.

Provided is a double braid rope structure which is provided with an inner core and an outer cover. In the double braid rope structure (10), the inner core (3) includes high strength and high modulus fibers with a yarn tenacity of 20 cN/dtex or higher and a yarn elastic modulus of 400 cN/dtex or higher, and has a ratio of yarn length/rope length of 1.005 or more and 1.200 or less, the rope length being determined as a length of a cut section (V) cut to a certain length from the rope structure (10), and the yarn length being determined as an average value of lengths of yarns constituting the inner core of the cut section (V).

A cord comprises a braided sheath of strands having an outer surface, an inner surface, and a central hollow portion defined by the inner surface and having a volume and a core within the central hollow portion of the tubular braided sheath, such that when the cord is in a relaxed state the tubular braided sheath has a cylindrical shape and a relaxed volume of the central hollow portion wherein the core does not fill the relaxed volume of the central hollow portion of the tubular braided sheath; when the cord is in a longitudinal tensioned state, the tubular braided sheath elongates under the longitudinal tension such that a tensioned volume of at least a part of the central hollow portion of the tubular braided sheath is less than the relaxed volume; and the inner surface of the tubular braided sheath of tensioned volume contacts and cinches a surface of the core.

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 30mm, 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 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 30mm, 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 hoist system includes a wire rope cable having a first end and a second end. The wire rope cable further including multiple strands twisted into a helical shape. The hoist system further including a lifting mechanism configured to attach to the first end of the wire rope cable. The lifting mechanism including at least one of a rotating drum and a set of frictional rollers. The hoist system further including a motor configured to rotate the lifting mechanism; and a housing configured to house the lifting mechanism, the motor, and at least part of the wire rope cable.

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.