| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-pressure fuel injection pipe having a bending part for use in a common rail system and its bending technique, which can prevent a fatigue rupture of the bending part as much as possible. <P>SOLUTION: In the high pressure fuel injection pipe, the ratio of the thickness to the outer diameter of the injection pipe is 0.3 or less, there is provided at least one bending part R having a length 2.7 times or less larger than the outer diameter, and the bore oblateness of the bending part is 9% or less. The bending method is characterized by flattening a portion of a small-diameter metallic pipe to be processed which corresponds to the bending part while retaining the pipe to be processed by a bending tool, so as to bend the portion as it remains flattened. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
