A metal roof panel includes a rib with a unique shape. The rib is bilateral with upwardly angled sides that each transition into an indentation, with both indentations transitioning into a central flat apex. Between each rib is a channel, preferably including at least one raised surface. The lower surface of the channel between the raised surfaces, and the top of the raised surfaces, are substantially planar and parallel to the flat surface of the apex of the panel. A unique method of manufacturing the roof panel employs a roll machine configured to shape a piece of sheet metal into the roof panel by modifying the shape in many small increments, which allows the final product to have a fairly intricate bend pattern.

A metal roof panel includes a rib with a unique shape. The rib is bilateral with upwardly angled sides that each transition into an indentation, with both indentations transitioning into a central flat apex. Between each rib is a channel, preferably including at least one raised surface. The lower surface of the channel between the raised surfaces, and the top of the raised surfaces, are substantially planar and parallel to the flat surface of the apex of the panel. A unique method of manufacturing the roof panel employs a roll machine configured to shape a piece of sheet metal into the roof panel by modifying the shape in many small increments, which allows the final product to have a fairly intricate bend pattern.

Provided is a clad steel plate with excellent thermal conductivity that can be used suitably in cookware and the like. The present invention is a three-layer clad steel plate having a carbon steel base material and stainless steel mating material disposed respectively on both surface sides of the base material, wherein a plate thickness ratio L given by Equation (1) is 1.0-5.0 and at least one surface of the clad steel plate has a plurality of protrusions and recesses. Plate thickness ratio L=the plate thickness of the base material/the total thickness of the mating material . . . Equation (1) Here, the base material thickness and the mating material thickness are the thicknesses at the protrusions.

Provided is a clad steel plate with excellent thermal conductivity that can be used suitably in cookware and the like. The present invention is a three-layer clad steel plate having a carbon steel base material and stainless steel mating material disposed respectively on both surface sides of the base material, wherein a plate thickness ratio L given by Equation (1) is 1.0-5.0 and at least one surface of the clad steel plate has a plurality of protrusions and recesses. Plate thickness ratio L=the plate thickness of the base material/the total thickness of the mating material . . . Equation (1) Here, the base material thickness and the mating material thickness are the thicknesses at the protrusions.

A method for manufacturing a clad steel pipe is provided, wherein the clad steel pipe is manufactured by using a clad steel plate as a raw material. The clad steel plate comprises a base layer (1) and a clad layer (2) roll-bonded with the base layer (1). The method for manufacturing a clad steel pipe comprises the steps of forming, welding, and deburring; both sides of the clad steel plate are bent towards the base layer (1) side of the clad steel plate, then the forming step is carried out, and after the forming step, the opening faces of the resultant pipe blank are all in a form of the clad layer (2). According to the method for manufacturing a clad steel pipe, a clad steel pipe is manufactured by using a clad steel plate as a raw material. Thus, continuance and high efficiency of a high-frequency longitudinal welding pipe unit is fully utilized, subsequent non-continuous processes are not necessary, and the corrosion resistance at the weld of the clad steel pipe is ensured.

A method for manufacturing a clad steel pipe is provided, wherein the clad steel pipe is manufactured by using a clad steel plate as a raw material. The clad steel plate comprises a base layer (1) and a clad layer (2) roll-bonded with the base layer (1). The method for manufacturing a clad steel pipe comprises the steps of forming, welding, and deburring; both sides of the clad steel plate are bent towards the base layer (1) side of the clad steel plate, then the forming step is carried out, and after the forming step, the opening faces of the resultant pipe blank are all in a form of the clad layer (2). According to the method for manufacturing a clad steel pipe, a clad steel pipe is manufactured by using a clad steel plate as a raw material. Thus, continuance and high efficiency of a high-frequency longitudinal welding pipe unit is fully utilized, subsequent non-continuous processes are not necessary, and the corrosion resistance at the weld of the clad steel pipe is ensured.

A metal roof panel includes a rib with a unique shape. The rib is bilateral with upwardly angled sides that each transition into an indentation, with both indentations transitioning into a central flat apex. Between each rib is a channel, preferably including at least one raised surface. The lower surface of the channel between the raised surfaces, and the top of the raised surfaces, are substantially planar and parallel to the flat surface of the apex of the panel. A unique method of manufacturing the roof panel employs a roll machine configured to shape a piece of sheet metal into the roof panel by modifying the shape in many small increments, which allows the final product to have a fairly intricate bend pattern.

A metal roof panel includes a rib with a unique shape. The rib is bilateral with upwardly angled sides that each transition into an indentation, with both indentations transitioning into a central flat apex. Between each rib is a channel, preferably including at least one raised surface. The lower surface of the channel between the raised surfaces, and the top of the raised surfaces, are substantially planar and parallel to the flat surface of the apex of the panel. A unique method of manufacturing the roof panel employs a roll machine configured to shape a piece of sheet metal into the roof panel by modifying the shape in many small increments, which allows the final product to have a fairly intricate bend pattern.

A Cr-containing ferritic stainless steel sheet is desired with improved corrosion resistance and rust resistance as well as improved ridging resistance. To achieve these results, the ferritic stainless steel sheet derives the relationship between Ap, which shows the -phase rate at 1100 C. due to a predetermined ingredient, and Sn in ferritic stainless steel which becomes a dual phase structure of + in the hot rolling temperature region, applies and adds Sn, and hot rolls the steel to give a total rolling rate of 15% or more in 1100 C. or higher hot rolling to thereby obtain ferritic stainless steel sheet which has good ridging resistance, which also has excellent corrosion resistance and rust resistance, and which can be applied to general durable consumer goods, wherein 0.060Sn0.6340.0082Ap and 10Ap70.

A Cr-containing ferritic stainless steel sheet is desired with improved corrosion resistance and rust resistance as well as improved ridging resistance. To achieve these results, the ferritic stainless steel sheet derives the relationship between Ap, which shows the -phase rate at 1100 C. due to a predetermined ingredient, and Sn in ferritic stainless steel which becomes a dual phase structure of + in the hot rolling temperature region, applies and adds Sn, and hot rolls the steel to give a total rolling rate of 15% or more in 1100 C. or higher hot rolling to thereby obtain ferritic stainless steel sheet which has good ridging resistance, which also has excellent corrosion resistance and rust resistance, and which can be applied to general durable consumer goods, wherein 0.060Sn0.6340.0082Ap and 10Ap70.