Abstract: A fuel inlet comprises an inlet pipe, a breather tube, a retainer, a spiral groove, and the like. The inlet pipe is formed by processing a metal pipe and has an expanded portion, a taper portion, and a main body in the order from the fuel port. The expanded portion is formed by increasing the diameter by bulging. In order to prevent defects in the pipe such as cracks from being caused during bulging, SUS304, SUS304L, or SUS436 according to JIS is used as the material of the pipe. The diameter of the main body is 25.4 mm and the diameter of the expanded portion is 50 mm. A spiral groove on which a screw-type fuel port cap can be screwed is formed in the vicinity of the open end of the expanded portion, by crimping the inlet pipe and the retainer together. On the outer surface of the expanded portion in the vicinity of the open end is provided an outer-cylinder-like flange formed integrally with the inlet pipe.

Abstract: A method of manufacturing a fuel inlet having an improved anti-rust property. As material for an inlet pipe 2 and a breather tube 4, stainless pipes are used. A pipe expanding process in which an end portion of the inlet pipe 2 is enlarged in diameter to form a filling part 6, a screw-thread forming process in which a helical groove 12 is formed on a periphery of the filling part 6, a welding process in which the breather tube 4 is welded to the inlet pipe 2, and a coating process in which a cationic electrodeposition coating is applied to a fuel inlet 1 after the welding process are performed in turn, thereby obtaining the fuel inlet 1 having an improved anti-rust property.

Abstract: A fuel inlet comprises an inlet pipe, a breather tube, a retainer, a spiral groove, and the like. The inlet pipe is formed by processing a metal pipe and has an expanded portion, a taper portion, and a main body in the order from the fuel port. The expanded portion is formed by increasing the diameter by bulging. In order to prevent defects in the pipe such as cracks from being caused during bulging, SUS304, SUS304L, or SUS436 according to JIS is used as the material of the pipe. The diameter of the main body is 25.4 mm and the diameter of the expanded portion is 5O mm. A spiral groove on which a screw-type fuel port cap can be screwed is formed in the vicinity of the open end of the expanded portion, by crimping the inlet pipe and the retainer together. On the outer surface of the expanded portion in the vicinity of the open end is provided an outer-cylinder-like flange formed integrally with the inlet pipe.

Abstract: A method of manufacturing a fuel inlet having an improved anti-rust property. As material for an inlet pipe 2 and a breather tube 4, stainless pipes are used. A pipe expanding process in which an end portion of the inlet pipe 2 is enlarged in diameter to form a filling part 6, a screw-thread forming process in which a helical groove 12 is formed on a periphery of the filling part 6, a welding process in which the breather tube 4 is welded to the inlet pipe 2, and a coating process in which a cationic electrodeposition coating is applied to a fuel inlet 1 after the welding process are performed in turn, thereby obtaining the fuel inlet 1 having an improved anti-rust property.

Abstract: A fuel inlet comprises an inlet pipe, a breather tube, a retainer, a spiral groove, and the like. The inlet pipe is formed by processing a metal pipe and has an expanded portion, a taper portion, and a main body in the order from the fuel port. The expanded portion is formed by increasing the diameter by bulging. In order to prevent defects in the pipe such as cracks from being caused during bulging, SUS304, SUS304L, or SUS436 according to JIS is used as the material of the pipe. The diameter of the main body is 25.4 mm and the diameter of the expanded portion is 50 mm. A spiral groove on which a screw-type fuel port cap can be screwed is formed in the vicinity of the open end of the expanded portion, by crimping the inlet pipe and the retainer together. On the outer surface of the expanded portion in the vicinity of the open end is provided an outer-cylinder-like flange formed integrally with the inlet pipe.