Method for showing cracks at valve top grinding end of high-power diesel engine in advance

Abstract

The invention provides a method for showing cracks at the top grinding end of a high-power diesel engine valve in advance, which comprises the following steps: S1, quenching a diesel engine valve blank to enable the hardness value of the valve blank to meet the design requirement so as to meet the subsequent processing and use requirements of the valve blank; S2, grinding the quenched valve blank, machining the valve blank into a valve finished product meeting the design requirement; S3, subjecting the air valve to low-temperature tempering treatment, thus the quenching stress is reduced, and the structure and cracks are stabilized; and S4, performing fluorescent flaw detection on the valve to detect whether grinding cracks exist in the valve or not. According to the method, the requirements and characteristics of valve top end machining are fully combined, reasons for cracks generated after grinding are analyzed, a treatment process method is added in a targeted mode, and grinding cracks on a valve finished product can appear in advance through the treatment process of quenching, grinding, low-temperature tempering and fluorescent flaw detection.

Description

technical field [0001] The invention belongs to the field of valve detection, and in particular relates to a method for making cracks at the grinding end of a valve top of a high-power diesel engine appear in advance. Background technique [0002] The characteristic of valve grinding is that it is easy to generate heat concentration at the grinding part during the grinding process, and when grinding metal materials with high hardness, such as diesel engine valves, it is easy to cause grinding on the machined surface due to heat concentration. However, some cracks generally do not appear immediately after the valve processing is completed, and will be delayed in the process of use, which will bring risks to the use of the whole vehicle of the engine. If the seal is not tight, the power of the engine will be reduced. In severe cases, the top may be broken during the working process, and the debris will fall into the combustion chamber, causing the piston to scuff the cylinder,...

AI Technical Summary

Problems solved by technology

[0003] In view of this, the present invention aims to propose a method to make the cracks at the grinding end of the valve top of the high-power diesel engine appear in advance, so as to solve the problem of poor detection accuracy caused by the cracks not being easy to appear during the detection process of the valve.