Process for producing common rail, and common rail

Abstract

A process for producing a common rail comprising a common-rail main body and a holder therefor, the main body and the holder containing, as chemical components, 0.01-0.3 mass% carbon, 0.01-0.5 mass% silicon, 0.01-3.0 mass% manganese, 0.0003-0.01 mass% boron, 0.001-0.01 mass% nitrogen, 0.01-0.5 mass%, excluding 0.01 mass%, aluminum, and 0.01-0.05 mass% titanium, having a phosphorus content reducedto 0.03 mass% or lower, a sulfur content reduced to 0.01 mass% or lower, an oxygen content reduced to 0.01 mass% or lower, and a total content of arsenic, tin, antimony, lead, and zinc reduced to 0.015 mass% or lower, with the remainder being iron and incidental impurities, and having a TLB value of 0.001% or higher. The process comprises an insert-metal insertion step, a liquid-phase diffusion bonding step, a laser peening step, and a surface-layer removal step.

Description

technical field [0001] The invention relates to a manufacturing method of a common rail in an accumulator fuel injection system of a diesel engine and a partially strengthened common rail using the manufacturing method. [0002] This application claims priority based on Japanese Patent Application No. 2009-059918 filed in Japan on March 12, 2009, and the content thereof is incorporated herein. Background technique [0003] In mechanical parts having fluid passages, stress concentration tends to occur at the ends of tubes through which fluid flows or where diameters change extremely, and fatigue failure as a result of fluid pressure fluctuations may become a problem. [0004] The common rail is a conduit-shaped component used to store light oil between the pump and the injector that pressure-feed light oil in the pressure-accumulation fuel injection system of a diesel engine. figure 1 The outline of the cross section of the common rail 1 is shown. The track hole 5 is the ma...

AI Technical Summary

Problems solved by technology

However, these methods are difficult to obtain the required processing shape with high precision and stability due to the great influence of laser irradiation, so they are not suitable for industrial production of common rail.

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