Abstract: A first contact joint screwed to the open end of a lubrication oil passage bore within the shaft of a track roller whose surface is to be rebuilt by welding material thereto, bears cooling medium inlet and outlet ports, bears an intake tube whose length is such that one end is centered axially between radial oil passages constituting branches for the oil passage bore such that a cooling medium fed to the intake terminal of an intake/exhaust sleeve borne by the first contact joint circulates through the track roller in the area of welding for maintaining the track roller surface at relatively low temperature during welding of the built-up material to the periphery of the track roller.