A material for porous metal body having a coil shape of a wire material wound in a helical shape, made of metal which having good thermal conductivity and can join by sintering; an average wire diameter Dw of the wire material is 0.05 mm to 2.00 mm inclusive, an average coil outer diameter Dc is 0.5 mm to 10.0 mm inclusive, a coil length L of 1 mm to 20 mm inclusive, and a winding number N is 1 to 10; and the plurality of materials for porous metal body are combined and sintered to form a metal porous body having a plurality of pores so that a pore ratio of the metal porous body is facilitated to be controlled.

A wire rope formed from a resin core and six strands, the resin core having an inner core with a circular cross section and an outer layer built up on the periphery thereof. The outer layer has a melting temperature lower than that of the inner core. The six strands are twisted together helically on the periphery of the resin core in an intertwining die in such a state that gaps are assured between the strands. The resulting wire rope is heated in a heating unit at a temperature higher than the melting temperature of the outer layer but lower than the melting temperature of the inner core. The wire rope is formed by subsequently compressing the six strands from the periphery thereof in a compressing die. The molten outer layer is hardened by natural cooling, after which the wire rope is taken up.

A wire (10) is disclosed. Said wire (10), when viewed in cross-section, has at least one first portion (12) and at least one second portion (14) that are interconnected by a third portion (16) in which the wire (10) has a reduced cross-section.

A hollow stranded wire (2) has a first layers (4) and second layers (6). The second layer is located outside the first layer. The first layer is formed by twisting eight first element wires (8) which are flat wires. The second layer is formed by twisting eight second element wires (10) which are flat wires. A ratio (Ww/Tw) of a width Ww to a thickness Tw of each flat wire is from 2 to 11. A twisting direction of the second element wires is opposite that of the first element wires. A twisting angle of each first element wire is not greater than 85. A twisting angle of each second element wire is not greater than 85. A ratio (D/T) of an average diameter D to a thickness T of the hollow stranded wire is not less than 5 and not greater than 20.

A coated PC steel stranded cable includes: a stranded cable in which a plurality of elemental wires each composed of steel are twisted together; an anti-corrosive coating having an outer circumferential portion that coats an outer circumference of the stranded cable; an outer coating that coats an outer circumference of the anti-corrosive coating; and an optical fiber provided at a position inwardly of an outer circumferential surface of the outer coating and corresponding to a strand groove in the stranded cable so as to follow expansion and contraction of the stranded cable.

Draw tape for cables including an elongated flexible element made of a helical multifilament rope composed of three filaments or strands helically wound about a common longitudinal axis. According to an additional feature, the rope is hammered. Still according to an improvement, the rope is externally covered by a jacket.

A pre-stressed concrete structure comprises a steel wire or a steel strand. The steel wire or steel strand has been pre-tensioned before curing of the concrete or grout. The steel wire or steel strand is provided with a zinc coating. The zinc coating has a weight ranging between 70 g/m.sup.2 and 950 g/m.sup.2. The steel wire or steel strand has an outer surface that is provided with indentions to provide mechanical anchorage points in the concrete structure. The steel wire or steel strand is further provided with a passivation layer in the form of a metal oxide layer.

A manipulation rope having an excellent torque transmittability is provided. A manipulation rope 2 is a rope 2 that is advantageously used as a manipulation rope for a medical instrument, and includes a side wire 6 or a side strand which is an outermost layer, the side wire 6 or the side strand having a spiral shape in which a flatness that is an aspect ratio obtained by a major axis being divided by a minor axis is greater than 1.00 and not greater than 1.10. An elongation of the rope at a time when a tensile load that is 1.0% of a breaking load is applied, is preferably not less than 0.04% and preferably not greater than 0.10%.

A stranded wire having a plurality of steel wires twisted together includes, in its cross section perpendicular to its longitudinal direction, a central wire as the steel wire, a plurality of first circumferential wires as the steel wires arranged in contact with the central wire to surround an outer periphery side of the central wire, and a plurality of second circumferential wires as the steel wires arranged in contact with the first circumferential wires to surround an outer periphery side of a region where the first circumferential wires are arranged, the second circumferential wires being greater in yield stress than the central wire and the first circumferential wires. The central wire is in surface contact with the first circumferential wires. The first circumferential wires are in surface contact with the second circumferential wires.

A manipulation rope having an excellent torque transmittability is provided. A manipulation rope is a rope that is advantageously used as a manipulation rope for a medical instrument, and includes a side wire or a side strand which is an outermost layer, the side wire or the side strand having a forming rate that is greater than 100% and not greater than 110%. The side wire or the side strand having been formed has a spiral shape in which a flatness that is an aspect ratio obtained by a major axis being divided by a minor axis is preferably not less than 1.01 and preferably not greater than 1.10. Further, an elongation of the rope at a time when a tensile load that is 1.0% of a breaking load is applied, is preferably not less than 0.04% and preferably not greater than 0.10%.