在油田管道安装及维修工程施工现场,经常遇到各种位置的管道焊接(包括切割),其中部分焊缝处于不理想的位置,又因设备、厂房、地表条件等的限制,再加上管道纵横交错,使这些焊缝的背面无法正常施焊(如图一),或者正常施焊代价昂贵,这时候一般采取“开天窗”的方法进行施工。 In the pipeline installation and maintenance of oilfield construction site, often encountered in a variety of locations of the pipeline welding (including cutting), some of the welds in an unsatisfactory position, but also because of equipment, factories, surface conditions and other restrictions, coupled with the pipeline Criss-cross, so that the back of these welds can not be normal welding (Figure 1), or normal welding is expensive, this time generally take “open skylight” approach to construction.