It is the welding supplementary machine for special use that design for bix-beam welding(flat angle weldingseam).The macheine use gantry style main struture, drivingin double-sides, controlled the speed stepplessly by converter;Tracing of welding seam uses the type of mechanic guiding roller;The up-down and right-left operation is controlled by pneumatic technology;In order to improve the effcidncy of big fillet welding,it is equipped with big electric current anddouble machine head(single welding seam)to process doublearcs and double wires weldings, installation of the machinehead is separated from arc-guiding mechanism;The devicewhich is used to protect solder, avoiding too much solderdrop down;lay-up of workpiece can use fixed frame and it can also be transmitted by roller, so it can from an assemblyline with other sets of machines