PIPELINE LAYING METHOD AND SET Russian patent published in 1998 - IPC

FIELD: construction of mainlines. SUBSTANCE: pipes are welded to separate branches of pipeline by girth weld using laser beam from inside the pipe. Laser beam welding of pipes enhances quality of weld material as compared with main material of pipe, thus preventing possible breakdowns of pipeline. After welding of girth welds, outer adjacent pipes are welded together by longitudinal seam. Movable device and platform with mounted-on processing equipment are used for pipe laying. Processing equipment includes laser, radiation transportation systems and replaceable magazines. The latter has inner and outer beam guides with focusing devices on ends of beam guides. Use of replaceable magazines makes it possible to carry out pipe welding to pipeline branches and simultaneously load in new pipes. EFFECT: reduced cost of manufacture, labour input and contamination of environment, enlarged operating capabilities. 4 cl, 5 dwg