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: Arc welding and overlaying, particularly with strip electrodes, and particularly for overlaying by the submerged arc welding process with strip electrodes, can be regulated as to the distribution of arc energy by using strip electrodes which are run through male and female gears so that the current input of the electrodes is adjusted as to uniformity across the width of the overlay path.