Abstract: The present invention relates to an apparatus suitable for use in the automatic welding of pipes. The apparatus according to the invention comprises a fixed part or rail band which is clamped around the pipe at a prefixed position and a moving part which is driven with an orbital motion along the rail band and supports a swinging welding torch, a welding rod feeding mechanism and a torch position adjusting mechanism. The swinging motion of the welding torch is produced by a pneumatic system which permits both the amplitude and the frequency of said swinging motion to be adjusted. It is also possible to produce high swing frequencies and various times of stoppage for the torch at the ends of the swinging motion.

Abstract: Apparatus which may be mounted upon a lay barge to weld an end of a pipe spool to an end of a pipeline used under water, includes a stand fixed to the pipeline to support and secure its outer end, a pipe spool support which may hold a spool in coaxial relationship with the pipeline and with one end abutting the outer end of the pipeline, a laser positioned to direct a beam of coherent radiation along the axis of the pipeline, a reflection system including a mirror mounted for movement through an arc of 360.degree. in the path of the laser beam to reflect that beam radially on the abutting ends of the pipeline and pipe spool, and a laser energy source for generating a beam of sufficient intensity to weld together the abutting ends of the pipeline and the pipe spool.