油气田调整改造时,常有伴生气新旧管线对接施工。对于一些较大口径的输气管线,若管内余气清除不净,对接时就会着火,火沿管子向里着,不仅会把管线烧坏,而且影响施工,在没有合适隔离球的情况下,很难对接,在施工中可以采用下列方法:(1)带火割断旧管线,并割掉一节,然后 During the adjustment and reconstruction of oil and gas fields, the construction of old and new pipeline with associated gas will often be carried out. For some larger diameter gas pipelines, if the gas in the pipe is not completely removed, the pipe will catch fire and the fire will move along the pipe. This will not only burn the pipelines, but also affect the construction. In the absence of proper ball isolation , It is difficult to butt, in the construction of the following methods can be used: (1) cut off the old line with fire and cut off a section, and then