Steel Sheet Used to Manufacture Pipe and Having Corrosion-Resistant Properties Against Fuel Vapors, and Pipe and Fuel Supply Pipe That Use Same

Abstract

Provided is a steel sheet for manufacturing a pipe having corrosion resistance against fuel vapor of fuel such as gasoline, light oil, bioethanol or bio-diesel fuel, and a pipe and a fuel supply pipe. In the steel sheet for manufacturing a pipe, a Fe—Ni diffusion layer and a softened Ni layer which is provided on the Fe—Ni diffusion layer are formed on a surface of a steel sheet, and a thickness of the softened Ni layer is set to a value which falls within a range of 0.9 to 8.1 μm thus having corrosion resistance against fuel vapor. In the pipe and the fuel supply pipe, a Fe—Ni diffusion layer and a softened Ni layer which is provided on the Fe—Ni diffusion layer are formed on an inner surface of a pipe formed of a steel sheet, and a thickness of the softened Ni layer is set to a value which falls within a range of 0.9 to 8.1 μm. In a fuel supply pipe 20 for supplying fuel to a fuel tank 23, the fuel supply pipe includes: a large-diameter pipe portion 21 through which the fuel passes; and a small-diameter pipe portion 22 which makes an upper portion of the large-diameter pipe portion and a lower portion of the large-diameter pipe portion communicate with each other for ventilation, and a Fe—Ni diffusion layer and a softened Ni layer which is provided on the Fe—Ni diffusion layer are formed on an inner surface of at least the small-diameter pipe portion, and a thickness of the softened Ni layer is set to a value which falls within a range of 0.9 to 8.1 μm.

Dependencies are inferred from the claim text.