Calculation And Analysis For Directly Buried Heating Pipeline's Stress

The directly buried installation has been applying in the heating pipeline more and more. The work pressure and the diameter of directly buried pipe are enlarging according to the broadening of the heating area.The work pressure has reached 2.5MPa, and the diameter has reached DN1000mm in heating pipeline of china. The pipeline stress design method in Technical Specification for Directly Buried Heating Pipeline Engineering in City has some restrictions, doesn't contain the stress design method for high work pressure, big diameter pipeline. Directly buried installation's development demands more reasonable and more general methods offered for designers to use.This paper analyzes the problems of the active stress design way for directly buried heating pipeline, brings forward solutions and directions for the problems; compares several stress design methods for directly buried heating pipeline, puts forward points for the stress design method of high work pressure, big diameter pipe. The paper also discusses the failure situations for different pipeline parts such as straight pipe, bend, angle, tee, figures out the installation ways aiming at different failure situations; works out internet application of"Directly Buried Heating Pipeline's Stress Design and Analyse", which can process stress design calculation for pipeline of high work pressure, big diameter; designs a project with this internet application, analyzes and adjusts the layout of pipeline and some factors of pipeline parts according to the calculation results. The stress design is simplified by using this internet application. This paper also analyses some factors in directly buried pipeline stress, the analyzing results can provide references for engineering design.