Weld overlay system

A weld overlay system which weld overlays an outer peripheral surface of a tube with a circular cross-section, the weld overlay system comprising:

• a rotation drive section which rotates the tube around an axis of the tube;
• and
• a carriage configured to travel along a rail, the carriage supporting (i) rollers configured to engage with the tube;
• (ii) an elastic member arranged between the rollers and the carriage;
• and (iii) a welding unit that is configured to apply a weld material to the outer peripheral surface of the tube which is rotating, while the welding unit is advanced along an axial direction of the tube,
• wherein the welding unit includes:
• a welding torch which generates an arc in a region between the welding torch and the outer peripheral surface of the tube;
• and
• a weld material supply section which supplies the weld material to a region to be welded,
• wherein the welding torch is configured to be disposed in such a manner that a tip end of the welding torch is located at an angular position that is advanced at a predetermined angle in a direction opposite to a rotational direction of the tube, with respect to a top portion of the tube,
• wherein an opposite end of the welding torch opposite to the tip end is disposed on a rotation-direction side of the tube with respect to the top portion of the tube, and
• wherein a virtual line extending from the tip end of the welding torch through the opposite end of the welding torch is inclined at a predetermined angle in the rotational direction of the tube with respect to a reference line passing through a center axis of the tube and the tip end of the welding torch, when viewed from the axial direction of the tube.