Abstract:To study the safety of all-welded pipeline ball valves under geological disasters.In response to earthquake disasters, two natural seismic waves were selected from the PEER database according to the "Code for Seismic Design of Buildings", and one artificial seismic wave was synthesized using Simqke gr software as the seismic load. Then use the time history analysis method to calculate the seismic response of the valve. Aiming at the subsidence disaster, according to relevant documents and codes, a formula for calculating the subsidence load suitable for different pipe diameters and different buried depths is proposed. Then the safety of the valve under this load is calculated. The results show that under the earthquake and subsidence load, the dangerous positions of the valve appear at the connection position of the left and right valve body and the pipeline, which is consistent with the actual situation. Then use JB-4732 "Steel Pressure Vessel-Analysis and Design Standard" for evaluation. The results show that the valve has a large safety margin and is safe under earthquake and subsidence loads. The research method provides a parameter basis for the design of similar valves in the future, and at the same time provides a reference method for the ability of natural gas pipeline equipment and components to resist geological disasters in the future.