Abstract: A method for extracting the node force data in the ANSYS RST result file is presented by using the C++ program and the application programming interface provided by ANSYS. ANSYS is used to solve the finite element model of a subway vehicle's welding frame, and the RST file containing the node force data is obtained. Finally, the accuracy and applicability of the method is verified by comparing the node force data with the calculation results of the fatigue life calculation software Weld Fatigue.