Patent ID: 6935377

Claim:
A high-pressure fuel injection pipe having a connecting head, comprising: a thick steel pipe having a relatively small diameter and provided at its connecting end portion with a connecting head having an outer circumference formed into a seat face of either a frustrum shape or a frustrum shape having a spherical leading end portion for a mating seat portion, such that an annular groove formed in the inner side of said connecting head in accordance with the shaping of said head is of a shallow gently curvilinear contour and a connecting washer fitted on the outer circumference of a lower neck portion of said connecting head, wherein said connecting head is provided on the outer circumference of its lower neck portion with an at least two-stepped portion, and wherein said connecting washer is provided with a stepped portion corresponding at least partially to the stepped portion of said connecting head, so that the stepped portions may abut against each other.