Abstract: A system and process is provided for cladding the interior of plasticating barrels or any other interior surface. The cladding operation uses a laser head that carries out a spiral welding operation to create a smoother lining than is capable with conventional welding techniques. A number of different techniques can be used, including the use of feeding laser energy at one end of a tube to be reflected from laser aiming optics inserted through a second end of the tube. Unidirectional welding can be used to facilitate gravity as a smoothing agent. In another embodiment omnidirectional welding can be carried out using a shaped mirror and a donut-shaped laser pattern. The cladding operation can be simplified by baking a coating of the welding matrix and anti-abrasive material onto the interior of the surface to be clad prior to the welding operation.