Structural analysis method of in-service welding behavior of gas pipeline

The invention discloses a structural analysis method of the in-service welding behavior of a gas pipeline. The finite element calculation software ANSYS is utilized, and the method is carried out according to the following steps that the welding condition of the in-service welding of the pipeline is determined; an entity model of the pipeline and a sleeve is created, the solving constraints and the loads of a in-service welding temperature field are applied according to practical work conditions, and the in-service welding temperature field of the pipeline is obtained through solving; a result file of the in-service welding temperature field is read, and whether the possibility that the pipeline is burnt through exists or not is preliminarily judged according to the specific value of the highest temperature of the inner wall of the pipeline; and an entity structure analysis model of the pipeline and the sleeve is created, all structure analysis results of the in-service welding of the pipeline is obtained thr