Loading patent…
AssigneeNippon Steel Corporation
InventorsShunji Sakamoto, Akihiko Takahashi, Michio Kaneko, Toshio Tanoue, Kenji Kato, Naoto Ono, Masao Kikuchi
Estimating the term…
The present invention provides a fuel tank or a fuel pipe excellent particularly in the corrosion resistance of the outer surface in a salt damage environment, and is a fuel tank or a fuel pipe excellent in corrosion resistance characterized by: being formed by using a steel sheet or a steel pipe containing Cr of 9.0 to 25.0 mass % as the base material; on the outer surface thereof, having any one or more of welded portions, brazed portions and structurally gapped portions contacting components; and having one or more of metals, whose electrode potential in a 5%-NaCl aqueous solution at 30° C. is −0.4 V or less relative to a saturated calomel electrode, attached to at least a part or parts of said portion(s) of the outer surface in an electrically conductive manner.
A fuel tank or a fuel pipe excellent in corrosion resistance characterized by:
Dependencies are inferred from the claim text.
Drawings are temporarily unavailable. Open the PDF at USPTO
From the US filing history. Foreign family members aren’t listed.
Backward citations are indexed for grants only.
Electrodes characterised by the material: material for sacrificial anodes
Arrangement in connection with fuel supply of combustion engines or other fuel consuming energy converters, e.g. fuel cells; Mounting or…: fuel tanks
Fuel tanks: tank inlets
Coating by spraying the coating material in the molten state
Term end not estimated
The present invention relates to fuel-related members including the fuel tank and the fuel pipes of an automobile as the main examples and, more specifically, to a fuel tank and a fuel pipe excellent in the corrosion resistance of the outer surfaces in a salt-damage environment.
The latest calls for the environmental protection and the reduction of the life cycle costs of commodities have had repercussions on fuel related members, such as a fuel tank, a fuel pipe and the like, which are components of an automobile.
A tank produced by using a lead-plated steel sheet as the base material and applying paint coating thereto has long been used practically as the fuel tank of an automobile, but, in view of the latest requirements for the environmental protection, new base materials free of lead are being developed. In addition, taking a serious view of the environmental impact of painting work itself, the needs for the elimination of the painting which has been deemed indispensable for the conventional plated steel sheets have arisen.
FIG. 1(a) shows an example of a corrosion test piece simulating a flange portion of a fuel tank wherein the layers of a conductive adhesive are formed and metal foils are attached.
FIG. 1(b) is a sectional view taken on line A-A′ of FIG. 1(a).
FIG. 2(a) shows the shape and dimension of a corrosion test piece simulating a flange portion of a fuel tank.
The present invention is hereafter explained in detail.
In the first place, a steel sheet or a steel pipe containing Cr of 9 to 25% is used as the base material for a fuel tank or a fuel pipe according to the present invention.
Cr is the principal element which governs the corrosion resistance of a base material. When its content is below 9%, the effect of an attached metal on raising the pH value is not obtained sufficiently and the corrosion resistance of the outer surface becomes insufficient. On the other hand, since Cr is a solid solution hardening element, when its content exceeds 25%, the ductility of the base material is deteriorated and sufficient cold workability is not obtained. For this reason, the Cr content of a base material is limited to 9 to 25%.