In the construction of gas interruption joint of natural gas pipeline,it is strictly forbidden to group welding joints by force.Construction workers often have doubts about this prohibition. They think that in the process of welding joint set alignment,as long as the welding joint can be aligned,non-destructive testing is qualified. Feeling forced group only increases the residual stress of the weld,and has little effect on the safe operation of the pipeline. Therefore,the simulated forced group welding test is carried out. Through the analysis of the theoretical data such as bending and impact of the qualified simulated weld specimens by conventional non-destructive testing,it is concluded that the hardness of the forced group welding joint increases and the toughness decreases,and it is easy to cause micro-cracks in the welding process,resulting in cracking failure after commissioning. It can not effectively satisfy the conclusion of safe operation of pipeline.