A hot press member includes excellent indentation peel strength which has a tensile strength of 1780 MPa or more. A plating layer has at a surface thereof a 10-point average roughness Rzjis of 25 μm or less, and a steel sheet contains, in mass %, not less than 0.25% but less than 0.50% of C, 1.5% or less of Si, 1.1-2.4% of Mn, 0.05% or less of P, 0.005% or less of S, 0.01-0.50% of Al, 0.010% or less of N, 0.001-0.020% of Sb, 0.005-0.15% of Nb, and 0.005-0.15% of Ti, the balance being Fe and incidental impurities. The average crystal grain size of prior austenite is 7 μm or less and the volume proportion of martensite is 90% or more, within 50 μm in the thickness direction from the surface of the steel sheet excluding the plating layer.

A hot press member includes excellent indentation peel strength which has a tensile strength of 1780 MPa or more. A plating layer has at a surface thereof a 10-point average roughness Rzjis of 25 μm or less, and a steel sheet contains, in mass %, not less than 0.25% but less than 0.50% of C, 1.5% or less of Si, 1.1-2.4% of Mn, 0.05% or less of P, 0.005% or less of S, 0.01-0.50% of Al, 0.010% or less of N, 0.001-0.020% of Sb, 0.005-0.15% of Nb, and 0.005-0.15% of Ti, the balance being Fe and incidental impurities. The average crystal grain size of prior austenite is 7 μm or less and the volume proportion of martensite is 90% or more, within 50 μm in the thickness direction from the surface of the steel sheet excluding the plating layer.

Flatness of a hot-rolled steel sheet in a coil is improved when the hot-rolled steel sheet is wound with a mandrel in a hot-rolling process to manufacture a coil. The mandrel has a protruding shape with a center portion in an axial direction protruding from both end portions when seen from a lateral side in the axial direction. Regarding a peripheral length difference, which is a difference between a peripheral length of the center portion of the mandrel and a peripheral length at a predetermined distance from the center portion, the ratio of the peripheral length difference to the peripheral length of the center portion is preferably 0.0002 to 0.012. The protruding shape may be a trapezoidal shape or a polynomial function shape.

Flatness of a hot-rolled steel sheet in a coil is improved when the hot-rolled steel sheet is wound with a mandrel in a hot-rolling process to manufacture a coil. The mandrel has a protruding shape with a center portion in an axial direction protruding from both end portions when seen from a lateral side in the axial direction. Regarding a peripheral length difference, which is a difference between a peripheral length of the center portion of the mandrel and a peripheral length at a predetermined distance from the center portion, the ratio of the peripheral length difference to the peripheral length of the center portion is preferably 0.0002 to 0.012. The protruding shape may be a trapezoidal shape or a polynomial function shape.

A winding core tube with a uniformly rough surface including a rotary barrel is provided. A circular through hole is provided at the inner side of the rotary barrel, a rotating sleeve is fixedly connected at the circular through hole of the rotary barrel, a circular through hole is provided at the outer side of the rotating sleeve, a connecting shaft is fixedly connected at the circular through hole of the rotating sleeve, the length of the connecting shaft is larger than that of the rotary barrel, and sprayed particles are sprayed on the outer side of the rotary barrel.

A winding core tube with a uniformly rough surface including a rotary barrel is provided. A circular through hole is provided at the inner side of the rotary barrel, a rotating sleeve is fixedly connected at the circular through hole of the rotary barrel, a circular through hole is provided at the outer side of the rotating sleeve, a connecting shaft is fixedly connected at the circular through hole of the rotating sleeve, the length of the connecting shaft is larger than that of the rotary barrel, and sprayed particles are sprayed on the outer side of the rotary barrel.

Disclosed is a winding core tube with a uniformly rough surface, including a rotary barrel. A circular through hole is provided at the inner side of the rotary barrel, a rotating sleeve is fixedly connected at the circular through hole of the rotary barrel, a circular through hole is provided at the outer side of the rotating sleeve, a connecting shaft is fixedly connected at the circular through hole of the rotating sleeve, the length of the connecting shaft is larger than that of the rotary barrel, and sprayed particles are sprayed on the outer side of the rotary barrel.

Disclosed is a winding core tube with a uniformly rough surface, including a rotary barrel. A circular through hole is provided at the inner side of the rotary barrel, a rotating sleeve is fixedly connected at the circular through hole of the rotary barrel, a circular through hole is provided at the outer side of the rotating sleeve, a connecting shaft is fixedly connected at the circular through hole of the rotating sleeve, the length of the connecting shaft is larger than that of the rotary barrel, and sprayed particles are sprayed on the outer side of the rotary barrel.

A container includes an outer box, and a polygonal liner located within the outer box. The polygonal liner has a plurality of vertical walls. A continuous length of wire is located within the polygonal liner and forms a plurality of layers. Each of the layers is comprised of a series of wire loops arrayed polygonally along the vertical walls of the polygonal liner.

A container includes an outer box, and a polygonal liner located within the outer box. The polygonal liner has a plurality of vertical walls. A continuous length of wire is located within the polygonal liner and forms a plurality of layers. Each of the layers is comprised of a series of wire loops arrayed polygonally along the vertical walls of the polygonal liner.