| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide the more prefect sealing performance while preventing the generation of seizure and deformation of a metal by coating a pressure receiver seat surface part of a branch hole with the oil or performing the treatment for hardening the pressure receiver seat surface part with heat treatment, and thereafter, making a presser seat surface part of a branch pipe abut thereon for engagement. SOLUTION: A main pipe rail 1 as a common rail for diesel engine or the like is formed with a flow passage 1-1 inside of a core, and while formed with plural boss parts 1-4 with a space in the axial direction. Each boss part 1-4 is bores with a branch hole 1-2 communicated with the flow passage 1-1 and having a pressure receiver seat surface 1-3, and a presser seat surface part 2-3 of a connecting head part 2-2 of the branch pipe 2 is made to abut on the pressure receiver seat surface 1-3 of the main pipe rail 1 for engagement. In this case, the pressure receiver seat surface part 1-3 is coated with the oil or a part of the presser receiver seat surface 1-3 is hardened by quenching so as to prevent the generation of seizure and deformation at that part, and the excellent sealing performance is secured.</p> |
