Study On Roughness Detection Technology Of Irregular Surface

The surface roughness is the inherent property of the machined surface after the parts are machined.The three-stage disc of the high-pressure compressor of the aero-engine works in the state of high temperature,high pressure and high rotation speed.The stress concentration is easy to occur at the junction R,causing fatigue fracture and safety accidents.A certain type of engine suffered from continuous three-stage disc fatigue tear.The design department required testing the surface roughness of its transfer R.However,due to its special structure,it cannot be tested by conventional means,so it is necessary to design and study the measurement method and evaluation method.On the basis of learning and summarizing the theoretical and practical achievements of predecessors,this paper introduces the surface roughness detection methods commonly used in the maintenance field.In this paper,the particularity,complexity and main characteristics of the components on the aero-spacecraft are analyzed,and a surface roughness detection system for a special part of the aero-engine is designed according to the national and international standards.The system adopts the method compared with the commonly used detection means more targeted,according to the practical characteristics of measured parts of customized,auxiliary to design a special tooling,and revise the traditional calculation method of improved,make the measurement more accurate,more meaningful,to solve the implementation of the conventional method can not type irregular surface roughness detection problem.The feasibility of the proposed method and system is fully verified through theoretical calculation and a large number of comparison experiments for different parts.The accuracy of the system is verified by the calculation of uncertainty.The research results of this paper have certain practical significance for the detection of other complex surface roughness.However,the system is not a universal detection method because of its strong pertinence.The surface roughness of other irregular surface should be corrected and improved according to the actual situation.