The object of investigation are curved sections of thin-walled underground pipelines with a flowing liquid under the influence of dynamic loads. Purpose of the work - development of the theory and development of methods for studying the dynamic stress - strain state of curvilinear sections of thin - walled oil - gas pipelines with a flowing liquid under the influence of dynamic loads. As a result of theoretical scientific research, the problem of determining the frequencies and forms of intrinsic bending vibrations in the curvature plane of curvilinear sections of thin-walled large diameter (toroidal shells) pipelines with a flowing liquid, including aboveground gas and oil pipelines, with different termination conditions is solved. It is established that the difference between stresses on the outer and inner surfaces of the pipeline reaches And the difference between stresses on the middle and inner surfaces.