Modular apparatus for the feeding of electrode wire through great

Abstract

A multi-module system for advancing an electrode wire from a supply location to a field welding station via a plurality of spaced conduit sections is described. Each conduit section is succeeded and preceeded by a plurality of wire-advancing heads, with the front-most head adjacent the welding station being driven at constant speed and the remaining heads being driven at a variable tension. The tension in the variable-tension heads is initially set to advance the wire through the conduit sections in a continuous serpentine-like path. When the tension in the wire downstream of the forward-most head increases to impart a 'straightening' component to the advancing wire, the forward-most head generates a control signal which is fed back via a regulator on the rear-most head to successively vary the tension in the successive rear heads in a successively decreasing manner corresponding to the decrease in total resistance of the wire tension seen by such successive heads. Such distribution of correcting force applied to the successive heads results in a rapid and effective restoration of the serpentine-like wire path through the system.