Research On Dynamic Characteristics Of Tubular Structure And Diagnosis Method Of Welding Crack

Welding technology in an important part of manufacturing, in many important fields, such as automotive, space navigation, shipbuilding, electronic information industry development has made great contribution. Now, however, the welding technology also can not assure welding structure without crack. Welding structure in the long-term mechanical load, environmental temperature, and all kinds of corrosion conditions, often produce crack in weld, and cracks not only brought many difficulties to production, can also bring disastrous accidents.This paper studies a kind of dynamic characteristics of tubular welding structure before and after crack and the fault diagnosis method. Using ANSYS software structure of static analysis and modal analysis. Compare the results of static analysis of the crack. The natural frequency of structure is obtained by modal analysis.A modeling test analysis system, incentive and response time domain signals measured structure was obtained, using the frequency domain method for parameter identification, get the modal parameters of the system. In this paper, based on this, the finite element modal analysis and experiment modal analysis results, better proves the reliability of the finite element modal analysis.This paper, by using power spectrum analysis for the structure impulse excitation response signal processing, was studied under different crack length is the structure of the pulse response power spectrum diagram of signal, is proposed based on fault diagnosis method of power spectrum analysis of crack and basis.