Abstract: Considering the influences of horizontal through crack on the fatigue life,the formula of strain energy of cracked pipe is introduced based on the theory of fracture mechanics.The dynamic model of pipe unit with horizontal through crack is established by the finite element method.Based on the dynamic model of cracked pipe element,the dynamic equation of the pipe with horizontal penetrating crack is obtained.The studies show that the dynamic equation discovers the internal relation between the dynamic characters of pipe with horizontal penetrating crack and the structural parameters,material parameters and crack parameters.

Key words: horizontal through crack, pipe, finite element, dynamic equation