天然气管道爆破对同沟敷设管道的影响试验

The influence of gas pipeline blasting on the pipelines laid in the same ditch

为了分析天然气管道爆破对同沟敷设管道性能的影响,利用管道断裂控制试验场开展了X90全尺寸气体爆破试验,分析管道爆破对同沟敷设管道变形行为、管材性能的影响。研究表明:天然气管道爆破会引起同沟敷设管道发生明显的弯曲、压扁变形,且变形管段中间部位的椭圆度较大;在热辐射作用下,钢管的性能发生了明显变化,裂纹的扩展抗力降低,且随着壁厚增大,显微硬度呈先升高再降低的趋势,受热层厚度约为700μm;热辐射能显著影响钢管的微观组织,受热部位表面组织晶粒发生一定的粗化,失去了原有生长取向,而深层组织的变化较小。

In order to study the influence of pipeline blasting on the performance of the pipelines laid in the same ditch,X90 full-scale gas blasting test was carried out based on the pipeline cracking control test field.In this test,the influence of pipeline blasting on the deformation behaviors and material properties of the pipelines laid in the same ditch was analyzed.It is shown that the blasting of natural gas pipeline can lead to bending deformation and flattening deformation of the pipelines laid in the same ditch,and the ovality is higher in middle section of the pipeline.Under the effect of heat radiation,the performance of the steel pipelines changes significantly.The propagation resistance of cracks decreases,the microhardness rises first and then decreases with the increasing of wall thickness,and the thickness of the heated layer is about 700μm.Heat radiation can change the microstructure of steel pipes obviously.The crystalline grains in the surface structure of heated position get coarse,the original growth orientation changes,and the structure in the deep part changes less.