On November 22th 2013, in Qingdao, the Huangdao, pipeline exploded. In this accident 62 people died and 136 people were injured. The survey shows that the drainage pipe explosion overpressure and object debris were the main reasons for the huge damage. There are many concrete fence obstacles in the pipelines that may increase the explosion overpressure. In order to study the effect of obstacles on pipeline explosion, a 3m-long, 100mm-diameter device was built for oil and gas pipelines explosion tests. The device consists of 2 short pipelines and all kinds of obstacles can be installed in the second one. In the experiments weak ignition was used to ignite the mixtures of propane and air. The distribution and variation of overpressure in the pipeline were investigated with obstacles at different blocking rates, quantities and spacing.