Orbital welding of closely spaced tubes - without using a wire feed drive mounted on the rotatable assembly

摘要

Orbital welding appts. has wire which is fed to the welding zone by wire feed mechanism operable by differential rotation of two drives operatble at different speeds. One drive carries a welding electrode and the wire feed mechanism. Both drives have openings allowing entry of tube to be welded. The drives cooperate with auxiliary drives which fit into the respective openings in the main drives. The auxiliary drives are guided across an opening in a housing enclosing the drives using a bridge piece securable to the housing across the opening. The apparatus permits orbital welding of very closely spaced tubes without using a wire feed drive motor mounted on the rotatable assembly. Both TIG and MIG arc welding methods may be performed or any method involving the feeding of wire into the weld zone.