An apparatus for applying weld metal for the purpose of hard-facing of metal plates (10) and a method of operation of the apparatus. A metal plate (10) is moved through an apparatus in which there are weld heads (43) including welding electrodes (49). The metal plate has a slight induced convexity in the region of the welding heads so that an accurate distance is maintained between the welding electrode and the surface of the metal plate. The convexity is formed by a wheel assembly (31) under the plate and the wheel assembly may also include cooling means (38). The advantage of the flat plate system is that long lengths of plate may be hard-faced.
