Abstract: An improvement to orbital welding heads and welding systems for welding pipe and tubing butt joints, consisting of a removable or retractable detector module in the welding head for sensing the proper alignment of the welding head to the pipe joint prior to welding. The module contains a light source that shires a light beam on the pipe wall, and a detector with associated circuitry and output indicators to signal when the reflected light is interrupted by the presence of a seam or pipe joint. The module may be in the form of a battery powered module that with the use of sleeves fits into the viewing port of a variety of welding heads, or it may be an integral capability that retracts into the side of the weld head out of the way of the welding tip orbiting mechanism.